Wednesday, December 30, 2009

Top 10 weather stories of 2009

Environment Canada's Dave Phillips released his Top 10 weather stories of 2009 list today.. an annual look at the top weather events across Canada. The number one story was the "summer of our discontent", a summer which was too cool and wet for most, too hot and dry in BC. Other top weather stories were the record ice-jam flooding on the Red, the Toronto area tornado outbreak, and the prolonged 9 month spell of below normal temperatures in the Prairies. What do you think was the top weather story for Winnipeg in 2009? Cast your vote on my blog poll! Say goodbye to 2009.. here's looking to a warm and pleasant 2010!

Friday, December 25, 2009

Snow and blowing snow moving into southern MB.. travel conditions to worsen

The next wave of snow from a strong winter storm system over Iowa is spreading over southern MB this morning from the southeast. Visibilities will be lowering through the day as gusty north winds to 50 or 60 km/h combine with falling and fresh snow to produce blowing and drifting snow. This will make for poor travelling conditions today into tonight across southern MB highways, especially through the Red River valley (see Pembina webcam for latest conditions). Travel is not advised this morning across most ND highways and a few over southern MB. Consult MB highways and ND highways for latest road information.

Thursday, December 24, 2009

Snow event begins.. 10-25 cm likely over southern MB through Christmas

Those hoping for snow for Christmas are getting their wish.. snowfall has begun over southern MB today, and will likely continue through Friday before tapering off Saturday. The snow today is the initial wave of the storm system being supported by a trough of low pressure moving in from Saskatchewan. This first wave of snow will bring about 2-8 cm of snow to southern MB today before it dissipates later today into this evening. Another round of snow will move in by Christmas morning from the south as the strong winter storm system pushing into Iowa spreads a large area of precipitation northward. This next wave will likely bring another 5-15 cm of snow to southern MB with the highest amounts near the US border. In addition winds will be increasing Friday from the north which will give reduced visibilities in snow and blowing snow resulting in poor travelling conditions for Christmas day. All told, snowfall totals over the next couple of days will range from 10-15 cm in Winnipeg to 25 cm over the southern and western Red River valley. Note that winter storm and blizzard warnings have been posted for parts of North Dakota and Minnesota due to this storm system.

Monday, December 21, 2009

Winter storm threatens holiday travel plans for areas south and east of Manitoba

A storm system is forecast to develop over the southern Plain states Tuesday into Wednesday, which will then move northeast and intensify into a strong winter storm Thursday into Christmas Day. Current indications are this storm will track from northern Texas into Wisconsin by Friday, with heavy snow and strong winds likely west of the storm track over portions of South Dakota, Nebraska, Iowa and Minnesota. A messy mix of freezing rain and ice pellets is possible along and east of the storm track. Snow from this system may extend into North Dakota and southern MB as well by Christmas Eve, although currently the worst of it is expected to stay southeast of us. Stay tuned on this developing situation especially if you have travel plans south or east of Manitoba for the holidays.

UPDATE: Dec 22: Winter storm watches have been posted for all of North Dakota and Minnesota right to the Canadian border for the potential of heavy snow beginning Wednesday and continuing through Christmas Day. Latest guidance indicates some snow will be moving into southern MB from this system as well Thursday into Friday although the heaviest amounts are still expected south of the border. Stay tuned..

Saturday, December 19, 2009

Snow drought continues

After the 2nd driest November on record with only 1.5 mm of melted snow for the month, the dry weather pattern has continued into December. As of the 18th, only 1.0 mm of melted snow has been recorded at Winnipeg airport this month, with a meager snowcover of 2 cm on the ground. This is the thinnest snow cover in Winnipeg for this time of year since 2002 when no snow was on the ground as of the 18th. And unfortunately for snowlovers out there, prospects for any significant snowfall over southern MB look low over the next week. A weak system passing through southern MB tonight into Sunday may bring a dusting to 2 cm, but overall it looks dry over the upcoming week with no major snowfalls forecast for southern MB through Christmas. That's good news for those with holiday travel plans this week, but not the best news for those looking for some nice powder for snowmobiling or skiing. Long range models are forecasting a strong storm system developing over the southern US Plains moving into the Great Lakes mid to late next week, but it appears this system will stay well to our south and east. In the meantime, those wishing for snow will have to look with envy to the US East Coast this weekend where a strong nor'easter is expected to bring 20-50 cm of heavy snow from Washington DC to Boston.

Wednesday, December 16, 2009

Arctic chill easing.. moderating temps on the way

After several days of Arctic cold, temperatures will finally be moderating over southern MB over the next few days. A warm front will be pushing across southern MB tonight bringing clouds and a possibility of some snow (dusting to 2 cm) . This front will keep temperatures from dropping tonight, and will usher in temperatures in the minus single digits Thursday for the first time since December 6th. Slightly colder weather is forecast for Friday into the weekend although temperatures should be close to normal for this time of year (normal highs minus 11, normal lows minus 20)

Monday, December 14, 2009

Windchill is not a temperature!

This recent cold spell has once again shown that people (especially the media!) are often confusing windchill with an actual temperature. This appeared in an article today in the Toronto Sun - "The Edmonton International Airport recorded a low of -46.1C, with the mercury dropping to -58.4C with the windchill, outfreezing even the Arctic." Well, that's not exactly true. The mercury did indeed drop to -46.1C at Edmonton airport, but it never dropped to -58.4C. That was the windchill factor which isn't a temperature at all, but rather a value that estimates the cooling rate of the air given a certain temperature and wind speed.   With no wind, your body will lose heat  at a certain rate depending on the air temperature. If there's a wind, your body will lose heat at a faster rate because the wind erodes the warm insulating layer near your skin that keeps in heat. The faster the wind, the faster the heat loss, and the "colder" it feels since your body feels like it's losing heat at the same rate as a colder temperature.     

For example, let's say it takes 20 minutes for you to feel cold when it's -25C outside and no wind. And let's say it takes you 10 minutes to feel cold when it's -40C with no wind. Now, let's say it's -25C with a 30 km/h wind. Because of the wind, your body starts losing heat more quickly, and you start feeling cold after only 10 minutes. Your body will tell you, hey it must be -40C out here because it took 10 minutes for you to start feeling cold. But is it -40C outside? No, it's -25C. To you, it just feels like -40C because of the wind that accelerated your body's heat loss.  People will say it "feels like" -40 with the windchill.. which is a way of saying that the wind makes it feel colder than it actually is.     

Because of this, windchill should never be stated as a temperature value (like degrees C).. it really should be expressed as a cooling rate (e.g. -58.4CU "cooling units") but in Canada, it's officially displayed without any units. Media has become overly fascinated with the windchill (I guess because it sounds so much worse than the actual temperature!) to the point that often they're just giving windchill values instead of the actual air temperature! The problem with this is that people start quoting windchill values as actual temperatures (as in the Sun article), which they are not.

Temperature is a measure of how much heat energy a parcel of air holds. The more heat energy, the higher the temperature. Windchill on the other hand is an index that estimates the RATE of energy loss of an air parcel given its original heat energy AND a prevailing wind that helps to accelerate the amount of energy leaving the air parcel (i.e. cooling rate). So, temperature is the amount of heat energy an air parcel has.. windchill is the rate of cooling of that air parcel.

Look at it this way... You have a bucket of water at +5C. You put it outside, where the air temperature is a constant +2C, but a wind of 50 km/h is producing a windchill of -5. Will that bucket of water freeze? Of course not. The water will only cool down to the ambient air temperature.. +2C. It can't get any colder than its environment unless it's cooled by some other method (e.g. refrigeration) The windchill of -5 merely implies that the water will cool down to +2C at a rate equivalent to that if the water was outside at -5C with no wind. So instead of taking one hour to cool down to +2C, it will only take 10 minutes thanks to that 50 km/h wind. But the water temperature will never go below +2c, no matter how extreme the wind or windchill is. That's the effect of windchill. It describes an equivalent RATE OF COOLING, not an actual temperature. So if it's -20C with a -40 windchill, your car will likely still start if it's not plugged in because the battery will never get below -20C. On the other hand, if it's -40C with no windchill, your car will not start if it's not plugged in because the battery will cool off to -40C (given it's outside long enough). See the difference?

Before 2001, the Prairies used a windchill index that was given in watts/sq metre (e.g 1800 W/m2) This was a more scientifically valid measure of what windchill actually was.. a rate of cooling, expressed in the amount of energy loss in watts per square metre of area. However in 2001, the windchill was re-calculated and standardized for all of North America to the windchill index we use today, which was mainly based on the more common "equivalent temperature" index being used in Southern Ontario and the United States. A survey conducted at that time showed that most people found the watts/sq metre unit "too technical" a term to fully understand.

Saturday, December 12, 2009

You want snow?!

For those of us starving for snow, take a look at some of the photos coming out of the Muskoka area in Ontario. Some extremely heavy lake effect snowsqualls off Georgian Bay over the past 2 days have left 100-150 cm of snow in some communities! Click on the photo for some amazing video out of MacTier.. south of Parry Sound. (photos and video posted to The Weather Network)

Friday, December 11, 2009

Cold.. and getting colder - Bitter windchills developing this weekend

If you think it's cold out there, wait until this weekend. A bitterly cold Arctic airmass over northern SK will push into southern MB over the weekend, bringing even colder air along with bitter windchills to southern MB by Saturday evening into Sunday. Northwest winds will begin to increase Saturday afternoon, and increase up to 30 km/h Saturday night into Sunday. Temperatures will drop to the minus 30C mark Saturday night and only recover to the mid minus 20s on Sunday. Unlike the past week however, windchills will be more of a factor, with windchills in the minus 40 to minus 45 range Saturday night into Sunday. Brisk west winds and bitter windchills are expected to continue Monday into Tuesday.

Monday, December 07, 2009

Arctic cold descends on Prairies.. blizzard to affect central US Plains

A large Arctic ridge of high pressure has built into the western Prairies this morning, bringing the coldest weather of the season so far to much of the Prairies. Temperatures of -30 to -35C were widespread over Alberta and western SK this morning, including a record breaking -37C at Edmonton International. This Arctic ridge will settle over the southern Prairies today into Tuesday, bringing well below normal temperatures over the area. Afternoon highs will only be in the minus teens to -20 range over Winnipeg over the upcoming week, while nighttime lows drop into the -25 to -30 range. Minimum temperatures of -30 to -35 are likely over southwest MB over the next few nights. Get that block heater cord out!

Meanwhile a powerful blizzard is shaping up over the central US plains today, and will bring heavy snow and strong winds through Kansas, Nebraska, Iowa and southern Minnesota tonight into Tuesday.

Sunday, December 06, 2009

Balmy December weather 70 years ago

On this date in 1939, temperatures soared to a record December high of 11.7C in Winnipeg, the only time in Winnipeg climate history that a double digit temperature was reached in December. It was even warmer southwest of Winnipeg that day, with readings of up to 18C in places like Melita and Morden. Above normal temperatures and a lack of snow would stick around right into Christmas, leading to one of Winnipeg's only "green Christmases" ever recorded (the others were 1877, 1913, and 1997). Residents played golf, tennis and lawn bowling on Christmas day 1939 to take advantage of the snow free conditions.

Friday, December 04, 2009

Arctic blast pushing into Prairies

Arctic air has finally moved into the Prairies, and an even colder surge of Arctic air will be pushing into the Prairies today through the weekend thanks to a strong area of high pressure building down from the Yukon. This second blast of Arctic air is currently pushing into Alberta with strong northerly winds, and snow and blowing snow giving near blizzard conditions through central and southern AB. This area of snow will push into the northern US, but the accompanying cold air will push across the eastern prairies over the weekend into early next week, bringing well below normal temperatures across southern MB. Look for highs in the minus teens by early next week with lows in the minus 25 to minus 30 range.

Wednesday, December 02, 2009

Cold winds and open lakes = snowsqualls for some tonight through Friday

Colder weather is finally moving over southern Manitoba, ushered in by brisk northerly winds advecting colder Arctic air into the province for the first time in weeks. These winds are blowing over the still open waters of the Manitoba lakes, where ice formation has been delayed this year due to the prolonged mild weather in November. The result will be localized bands of lake effect snow off Lake Manitoba and Lake Winnipeg (particularly off the north basin). Northerly winds tonight and Thursday will set up snow bands immediately to the south of the lakes affecting areas through the central Interlake, as well as the Portage La Prairie and Beausejour areas. By Friday, the winds should veer slightly to the north-northwest which would push the snowbands a little further to the east. 10-20 cm of snow is possible under persistent snow bands while little snow is likely outside these areas. The cold weather is expected to persist for the next week or two, which will quickly freeze up the lakes over the next couple of weeks shutting down the lake effect machine.

UPDATE: see local radar image above from Thursday morning showing lake effect bands

November 5th warmest, 2nd driest on record

After a rather chilly October, the weather pattern flipped in November to produce one of the mildest and driest Novembers on record in Winnipeg and southern Manitoba. Temperatures rose to above normal values on the 6th and stayed above normal every day through the end of the month. Winnipeg airport finished with a monthly mean temperature of +0.8C, the mildest November since 2001 (+0.9C) and the 5th mildest November since records began in 1872. Temperatures reached double digits on 10 days during the month, twice as many as October, and tying 1981 with the second most double digit days in November. In fact, the average daily high of +7.1C in November was just about the same as October (+7.3C) Combined with the warmest September on record, the 3 month fall period of Sep, Oct and Nov ended up tied with 1953 as the 4th mildest fall on record in Winnipeg with an average temperature of +7.3C. (Winnipeg's warmest fall was 1963 at 8.6C)

The big story however was the dryness of the month. Total precipitation at Winnipeg airport was only 1.5 mm .. tying 1901 and 1939 as the second driest November on record in Winnipeg (driest was 0.8 mm in 1976) All of the precipitation fell as melted snow with no rain during the month. The month was dominated by almost daily sunshine and mild temperature from the 4th to the 24th.. making it feel more like October than November. The extended fall weather and lack of snow allowed farmers to continue burning their fields well beyond the usual end date of Nov 15th.. requiring the province to extend the requirement for burning permits into December.

All in all.. a fabulous fall month.

Tuesday, December 01, 2009

Snowfall slipping south of city

An Alberta clipper storm system is bringing an area of snow just south of Winnipeg this morning. Snow is falling from just south of the city to the US border, with the heaviest amounts across southwest MB into the southern Red River Valley. Radar indicates that 10-15 cm snow likely fell in a band from Virden to Morden (image left) overnight into this morning. Highways are snowcovered and slippery south and west of the city so be prepared for winter driving conditions if you are travelling south of the city today. This system will continue to slide southeastward today moving into northern Minnesota this afternoon. Gusty northwest winds behind this clipper will usher in colder air over all of southern MB tonight into Wednesday with temperatures finally returning to normal values for early December.

Sunday, November 29, 2009

Alberta clipper threatens snow for Tuesday

An Alberta clipper storm system is forecast to track across southern MB Tuesday, bringing the potential of the season's first significant snowfall over portions of southern MB. The center of the storm is expected to move across the Riding Mtn area early Tuesday tracking through the northern Red River valley and into the Whiteshell by Tuesday evening. The heaviest swath of snow is expected along and north of this storm track.. putting the most significant snow along and north of the TransCanada where 10-15 cm is possible. Snowfall amounts will drop off sharply south of this track with 5 cm or less likely. Gusty northwest winds will follow in behind the system bringing a drop in temperatures by Tuesday evening, as well as areas of blowing and drifting snow in open areas. Snowfall amounts will depend critically on the exact path of this system, so stay tuned on the progress of this potentially first wintery blast of the 2009-10 winter season.

UPDATE: Latest model guidance has shifted the track of Tuesday's system further south. As a result, the heaviest snow is now expected to fall over southwest Manitoba and over the southern Red River valley into SE Manitoba where 10-15 cm is possible. Winnipeg is expected to lie on the northern edge of the heaviest snow.. with 5 cm possible. Note that Winnipeg may get heavier amounts of snow if this system tracks a little further north than latest projections. Stay tuned..

Saturday, November 28, 2009

Above normal temps to end November.. colder weather to begin December

The above normal temperatures that have characterized most of November will continue through the end of the month before a change to colder weather just as the calendar flips to December. In the short term, generally quiet weather is expected over the next few days with cloudy to partly sunny skies, and afternoon temperatures near or slightly above the freezing mark, some 6 degrees above normal for this time of year. November 2009 will end up as the 3rd or 4th warmest November on record in Winnipeg since 1872, and barring any measurable precipitation over the next 3 days, will likely end up as the driest November since records began with only 0.5 mm total precipitation for the month.

By Tuesday, an Alberta clipper system will track through the Manitoba lakes and bring a threat of snow, especially through the Interlake areas. Gusty northerly winds on the backside of the system will draw in colder temperatures over southern MB by Tuesday evening, with temperatures finally dropping to normal or even below normal values for the beginning of December (normal highs -7C, normal lows -15C)

Tuesday, November 24, 2009

Sliding towards normal..

It was another pleasant day of sunshine and above normal temperatures over Winnipeg and the Red River valley, but things will be cooling off Wednesday and Thursday, with colder weather likely for next week. Still, temperatures are forecast to remain above the normal high of -5C this week, before cooling off to more seasonable values next week. The return of colder air will also increase the chances for some precipitation, likely in the form of flurries or snow over the next few days. For tonight, some light snow is possible mainly over SW Manitoba with some flurries possible over much of southern MB Wednesday as brisk northerly winds pump in colder air. The next chance of precipitation will be Friday as a low pressure system moves through the Interlake spreading an area of snow mainly north of the low, mixing with some rainshowers to the south. Behind this system, colder air is expected for the weekend into next week with a possibility of some snow Saturday into Saturday night. Winnipeg has not seen any measurable precipitation since the 1st of the month, but the dry streak will likely come to and over the next few days as colder and more unsettled weather moves in.

Sunday, November 22, 2009

Gusty Saturday sets new record high in Winnipeg

The mild November of 2009 continued into its third week, with record breaking temperatures on Saturday. In Winnipeg, the high of 13.4C at Winnipeg airport set a new record high for Nov 21st, eclipsing the previous mark of 11.1C in 1904. It was also the 10th day this month of double digit temperatures, twice the number recorded in October, and tying 1981 for the second most double digit days in November. The record breaking day was also accompanied by strong southerly winds gusting as high as 76 km/h at the airport Saturday afternoon. Although slightly cooler weather is forecast over the next few days, temperatures are expected to remain above normal through mid week and possibly into next weekend before hints of a change to colder weather by the end of the month into early December. Until then, Winnipeg is on pace to record its warmest November on record. As of the 21st, the mean monthly temperature at Winnipeg airport was +2.4C, over 7 degrees above normal and a degree warmer than the record warmest Novembers of 1899 and 1923 at 1.3C.

Friday, November 20, 2009

Dry spell entering 3rd week

With sunny skies and no precipitation forecast for the next few days, Winnipeg will be entering its 3rd week without measurable precipitation officially recorded at Winnipeg airport. The airport weather station measured 0.5 mm of melted snow early on the 1st of the month, and since then there has been no precipitation recorded, 19 straight days as of today. And long range forecasts don’t offer much in the way of significant precipitation over the next 5 days, although there may be some flurries by the middle of next week as some colder air moves in. All in all, unless there's a significant storm at the end of the month, it’s shaping up to be one of the driest Novembers on record in Winnipeg since 1976 when only 0.8 mm fell during the month, the driest November on record. This is in sharp contrast to the west Coast which has been deluged with rain this month due to frequent Pacific storm systems coming onshore. Some localities have recorded over 500 mm of rain since November 1st, including Squamish, Tofino and Port Alberni.

UPDATE: Winnipeg ended up with 1.5 mm for the month, tying 1901 and 1939 as the second driest November on record. Meanwhile, Port Alberni ended up with over 800 mm for November while Tahsis Village on the northwest coast of Vancouver Island ended up with over 1100 mm for the month!

Thursday, November 19, 2009

US climate experts predict mild weather continuing through December

NOAA's Climate Prediction Center (CPC) released its climate outlook for December today, and it shows that above normal temperatures are expected to continue through December over the the northern Plains (and southern Prairies) This outlook is very similar to CPC's November outlook which also called for above normal temperatures over the central continent. The mild weather outlook is mainly due to a strengthening El Nino which has now reached a moderate stage in the Pacific. This tends to bring warmer than normal conditions during the winter months over western Canada into the mid section of the continent. As a result, CPC is indicating better than even odds that the winter of 2009-10 will be above normal over our area. Precipitation is likely to remain below normal over us as well, as the North America storm track tends to take a "split flow" pattern during El Nino episodes. This split flow pattern brings a southern track of storms though the southern US (mainly California into the Gulf states) while a northern storm track affects BC into the northern prairies. This setup usually translates to drier and warmer than normal conditions over the southern Prairies between the two main storm tracks.

Saturday, November 14, 2009

Fine fall weather to continue through upcoming week

The exceptionally nice weather we've been enjoying this month will continue through the upcoming week with dry weather and above normal temperatures. Long range models continue to indicate Arctic air remaining well to our north, as a storm track takes storms across the northern Prairies or Territories, keeping mild Pacific airmasses over the southern Prairies. The result will be more of the same, with sunshine and temperatures in the 5-10c range through the next week at least.

Thursday, November 12, 2009

Double digit streak goes to 7 days.. 2nd longest on record for November

With temperatures hitting 11C today in Winnipeg, it marked the 7th day in a row of double digit highs in the city since last Friday. This is the 2nd longest streak of 10C days for November in Winnipeg since records began in 1872, second only to the 8 day streak from Nov 2-9, 1963. Note that we had only five double digit highs in all of October. The streak will end at 7 days as slightly cooler weather moves in Friday, however temperatures will remain above normal for the next week at least.

The top streak of 10C days in November in Winnipeg..

1. 8 days.. 1963 Nov 2-9 .. max 13.9C
2. 7 days.. 2009 Nov 6-12.. max 13.8C
3. 6 days.. 1975 Nov 1-6 .. max 23.9C
4. 5 days.. 1904 Nov 2-6 .. max 18.3C
4. 5 days.. 1899 Nov 2-6 .. max 15.6C
4. 5 days.. 1923 Nov 8-12.. max 14.4C

The most number of 10C days in a November in Winnipeg is 11 days in 1904 followed by 10 in 1981.

Monday, November 09, 2009

October in November continues

The fine late fall weather will continue for the next few days.. with double digits highs expected Tuesday and Wednesday before a frontal system brings in a chance of showers Thursday with slightly cooler weather for the end of the week. Temperatures however will remain above normal through the weekend into next week. In the near term, the mild 10+C weather will continue Tuesday, but gusty southerly winds will develop during the day with gusts to 60 or 70 km/h possible by the afternoon through the Red River valley.

Friday, November 06, 2009

Temperatures hit the 20C mark over SW Manitoba

Sunshine, snowfree ground and gusty south to southwest winds allowed temperatures to climb into the upper teens and low 20s across SW Manitoba today. The warmest spots were downwind of higher terrain with downsloping southwest winds coming off Riding Mtns and Turtle Mountain allowing temperatures to climb into the 20s.. well above the normal high of +2C this time of year. Temperatures were a little cooler in Winnipeg and the Red River valley thanks to a southerly valley wind, but were still well above normal. Some highs across southern MB today included..

Killarney....24.1C *
Dunrea.......23.8C *
Boissevain...23.4C *
Glenboro.....21.4C *
McCreary.....21.4C
Dauphin......20.9C
Melita.......19.1C
Portage......18.7C
Brandon......17.8C
Carman.......17.2C
Morden.......16.7C
Winnipeg.....12.7C

* from CWB Weatherbug mesonet

see also stats from MB Ag-Wx mesonet

Monday, November 02, 2009

Nice warmup by week's end

Models are indicating a nice warmup over southern MB by the end of the week, as a low pressure system moves across the northern Prairies spreading a mild Pacific airmass across much of the south. In southern MB,  sunny skies and temperatures of 10 to 13C are likely by Friday into Saturday, well above the normal highs of +3C for early November.  Temperatures will cool slightly for next week however long range guidance is suggesting that temperatures will remain near to above normal into mid November.   

Wednesday, October 28, 2009

Intensifying storm system to bring strong winds, rain and snow to southern MB Friday

A storm system over the southern US plains will move north and intensify Thursday into Friday, bringing a large swath of precipitation over southern MB on Friday. Rain from this system will spread over southern MB Thursday afternoon into Thursday night, and continue into Friday over the RRV and SE Manitoba. Heavy rainfall is possible with amounts of 20 - 40 mm in some areas Thursday night into Friday. Further west, precipitation will likely change to snow over the western RRV into SW Manitoba Thursday night into Friday, with significant accumulations possible, especially through the Pilot Mound area down into western and central ND. Increasing northerly winds of 50 to 70 km/h Friday will compound the situation, especially in areas with snow. There is still considerable uncertainty in the evolution of this upcoming storm system, especially with respect to where the rain/snow line will end up. This will have considerable impact on eventual rainfall and snowfall amounts. Stay tuned with updates on this developing situation.

Sunday, October 18, 2009

Mild Sunday over southern MB

After an unseasonably cold first half of October, temperatures finally climbed to above normal values over southern MB today with afternoon highs of 15-20C under partly sunny skies. Winnipeg reached a high of 16C, with 20C temperatures recorded over southwest MB, mainly south of Highway 2 in places like Melita, Boissevain, Glenboro, Treherne as far east as Carman. In fact, Melita was the national hot spot today at 21.6C. It was even warmer south of the border with temperatures reaching a summerlike 80F (27C) in Bismarck ND. At Winnipeg, the 16C reading was the warmest day of the month so far, and the first day with temperatures in double digits since Oct 3rd. The mild weather will be short lived however as a cold front moves through tonight, dropping temperatures back into the single digits for the rest of the week.

Friday, October 16, 2009

CPC winter outlook calls for milder than normal conditions for Prairies

NOAA's Climate Prediction Center (CPC) released its preliminary winter outlook for 2009-2010, and it's calling for milder than normal conditions over the Prairies for the upcoming winter. This is in response to the current El Nino that is expected to persist and possibly strengthen over the winter months. The first half of October has been well below normal due to a stubborn polar vortex over Hudson Bay that has maintained cold weather over much of the Prairies. There are hints that this pattern will relax over the next week or two allowing for more seasonal temperatures for the second half of October. The latest CPC 30 day outlook calls for milder than normal conditions over the Prairies through mid-November.

See the winter outlook from NWS Grand Forks for a more detailed discussion on the weather influences and trends expected for the Red River valley area this upcoming winter.

Saturday, October 10, 2009

First snow of the season hits Winnipeg

Only two weeks after summerlike weather, winter made a premature entrance over southern Manitoba with an early season snowfall over parts of the province Friday. Snow began in earnest over the Riding Mountain and central Interlake areas early Friday with 10-20 cm reported from Dauphin to Fisher Branch. By Friday evening, cold northwest winds on the backside of the system created snowsqualls off Lake Manitoba that pushed into Winnipeg, dumping 10 cm of snow in the city between 6 pm and midnight. The snow created many problems on area roadways with numerous accidents including 2 multi-vehicle pileups on the perimeter highway around Winnipeg. Intense snowsqualls also developed off Lake Winnipeg Friday night into Saturday producing 30 to 50 cm of snow north and east of Lac Du Bonnet. Temperatures will remain well below normal through the Thanksgiving weekend with occasional flurries from time to time. Another system moving through the Dakotas threatens more snow over southeast Manitoba on Monday.

Thursday, October 08, 2009

Heavy snow event shaping up for Riding Mountain/Dauphin area Friday

A low pressure system over southwest Saskatchewan this morning will track into southwest Manitoba by Friday morning, bringing an area of heavy snow with it. The system will be slow moving and intensifying due to strong upper support and lift in the atmosphere, which will bring a relatively small but intense area of snow over southwest Manitoba Friday into Friday night. At this point, it appears that the Riding Mountain area including Dauphin will bear the brunt of the heaviest snow.. with models indicating that 15 - 30 cm of snow is possible in some areas by Saturday morning. A winter storm watch has been issued for the area advising of the potential of this heavy snow event. Stay tuned..

And although it's a little early in the season for a significant snowfall, it's not unusual. Just 4 years ago on October 5 2005, a record early season snowstorm dumped up to 45 cm of snow over southwest Manitoba near Pilot Mound area as well as North Dakota, with 5-10 cm in Winnipeg. Here's a list of the earliest October snowfalls of 2 cm or more in Winnipeg..

Oct 1 1996 ...... 4.0 cm
Oct 2 1950 ...... 12.7 cm
Oct 4 1952 ...... 8.6 cm
Oct 5 1876 ...... 11.4 cm
Oct 5 1925 ...... 5.1 cm
Oct 5 2002 ...... 4.0 cm
Oct 5 2005 ...... 5.0 cm (est)
Oct 7-8 1985 .... 13.8 cm
Oct 8 1959 ...... 2.5 cm
Oct 8 1875 ...... 2.5 cm
Oct 8 1987 ...... 2.0 cm
Oct 9 2009 ...... 10.0 cm
Oct 10 1883 ..... 10.9 cm
Oct
10 1959 ..... 5.1 cm
Oct 10 1919
..... 3.3 cm

Saturday, October 03, 2009

Staying cool... snow possible by end of week

Cool weather will be with us for the week ahead with generally cloudy skies and temperatures remaining below normal. Tuesday looks like the nicest day of the week with partial sunshine and temperatures near normal. A cold front will then move across southern MB Wednesday bringing gusty northwest winds and below normal temperatures. Even colder air will be moving in by Friday as a second cold front crosses the area, bringing a chance of snow over much of southern MB Friday into Saturday. Welcome to October!

Thursday, October 01, 2009

System to bring rain south and west of Winnipeg

A low pressure system moving through the Dakotas is spreading an area of rain over southwestern MB this morning. Rain will gradually spread into the Red River valley today but should stay mainly to the south and west of Winnipeg as the system stalls and pulls south. Rainfall amounts of 20-40 mm are forecast over western MB with 10-20 mm possible over the Red River valley south and west of Winnipeg. Areas north and east of Winnipeg should stay dry today into Friday.

Wednesday, September 30, 2009

Spectacular September salvages sorry summer - September 2009 warmest on record

After subjecting southern MB to 9 months of below normal temperatures, Mother Nature relented in dramatic fashion by delivering the warmest September on record across much of the southern Prairies. In Winnipeg, the month finished with an average temperature of 17.7C at YWG airport, over 5 degrees above the normal 12.3C and the warmest September in Winnipeg since records began in 1872. The month was nearly a full degree warmer than the previous warmest September of 1948 at 16.8C. In fact, September 2009 had a monthly mean of 19.0C through the 26th, before 4 days of cool weather at the end of the month shaved over a degree off the final average.

September 2009 was a summer-like month with plenty of sunny warm days, and only 4 days with measurable rain. The stretch between the 13th and 25th was especially nice, dominated by sunshine and 25-30C temperatures that was interrupted only one day with cloudy skies and a brief shower over the two week period. The month finished with an average temperature higher than any month of the year, the first and only time in Winnipeg’s climate history that September was the warmest month of the year. Every day from the 1st to the 27th was above normal with 19 of those days reaching a temperature of 25C or higher, the most 25C days of any September (previous record 16 days in 1940) and nearly twice as many as July had (10 days) Amazingly, no daily record highs were established during the month, highlighting the fact that it was the persistence of the warm weather that was the story, rather than any extreme heat. This was evident with the night-time lows, with no lows below 10C until the 22nd. A cool snap at the end of the month produced the season’s first frost on the 29th with a low of -2.4C at Winnipeg airport. Downtown however remained frost free all month.

Precipitation at the airport totaled 22 mm, less than half the average September monthly precipitation of 58 mm. Of the 22mm total, only 1 mm fell after the 11th. The sunny dry warm weather was a blessing for area farmers who needed an extended period of warm dry weather to make up for a slow growing season delayed by cool temperatures and rainfall. As a result, many crops were able to mature before the late frost, and be harvested in fine sunny conditions. The weather was also a boon to local beaches and golf courses, making up for some lost ground from a cool wet summer.

Overall, a September to remember! (see NCDC September summary for more info)

Tuesday, September 29, 2009

2009 growing season ends for most of southern Manitoba

Clear skies and a light wind allowed temperatures to drop to below freezing this morning across much of southern MB, officially ending the 2009 growing season. The exception was near Lake Winnipeg and western MB where clouds kept temperatures above freezing overnight (see map) At Winnipeg airport, the temperature dropped to a low of -2.4C, ending a 114 day growing season that began late due to a record freeze on June 6th.

At Winnipeg airport, the average date of the first fall frost is Sept 22nd so today's frost was a week later than "normal", although the first fall frost date varies quite a bit from year to year. Average date for the last frost in spring is May 23rd which gives an average growing season of about 121 days using airport data. Last year, the airport had a 116 day growing season (Jun 3rd - Sept 26th), virtually the same as this year.

Within the city of Winnipeg however, frost was not widespread this morning. The Forks downtown had a low of +1.4C, and in Charleswood, my station registered a low of +0.5C with just some some light frost noted. Downtown Winnipeg has a much longer growing season than the airport, due to the urban heat island effect that keeps night time temperatures warmer than rural areas. The average first fall frost downtown is Oct 5th, while the last spring frost is May 4th giving an average growing season of 159 days downtown, or 38 days longer than the airport. For most areas of the city, the length of the growing season lies somewhere between downtown and airport values.

Monday, September 28, 2009

Chilly today.. frosty tonight...

No, that's not a Wendy's menu order.. that's the weather forecast for Winnipeg and southern Manitoba for the next 24 hours as a northerly flow of cool air spreads over the province. Gusty north winds today will keep temperatures only in the 12c range this afternoon, with cloudy skies and occasional sprinkles or drizzle from weakening off lake streamers. For tonight, high pressure will be building over southern MB, bringing clearing skies and diminishing winds.. perfect conditions for frost formation overnight. In fact, much of southern MB will see its first frost of the season by Tuesday morning with overnight lows of zero to -3C expected. The exception will be areas near and to the west of the MB lakes which will be saved from frost by the warm lake waters. Patchy cloud cover will also save some localities from frost tonight. Tuesday looks like a nice day with sunshine mixing with a few clouds, lighter winds, and afternoon temperatures of 12-15C.

Friday, September 25, 2009

Strong winds to bring cool change for Sunday.. gales, high waves for MB lakes Sunday night

The extended summerlike pattern of September 2009 will come to an abrupt end Sunday as a storm system tracks across Manitoba and intensifies over northwest Ontario Sunday night. Strong northwest winds on the backside of this system will draw in much cooler air over southern MB Sunday into Sunday night, with gusts of 70 to 80 km/h likely by Sunday evening over much of southern MB, with 90-100 km/h gusts possible on the eastern shores of Lakes Winnipeg and Manitoba. These strong winds will combine with high lake levels to create large waves.. possibly 3-4 metres high, which may cause problems along the exposed eastern shorelines of the lakes. In addition, the strong winds may result in tree limb damage and local power outages since most trees are still full of leaves thanks to a warm frost-free September. A similar storm system on June 27th brought 100 km/h gusts over southern Lake Winnipeg and resulted in extensive power outages through cottage country into the Whiteshell due to fallen tree limbs and power lines.

Wednesday, September 23, 2009

September sets new heat record... big cooldown expected Sunday

The summer-like weather of September 2009 will be one for the record books. With a maximum temperature of 26C Wednesday, Winnipeg registered its 17th day in September with temperatures of 25C or higher. This eclipses the previous September record of sixteen 25C days set back in 1940. And it looks like we'll add a couple more to the total before the week is through as temperatures of 25C or more are forecast both Thursday and Friday. This is in stark contrast to a very cool July, the 5th coolest on record, in which Winnipeg saw only ten days of 25C or more. In fact, September 2009 will finish with an average temperature greater than July, the first time that has ever happened in Winnipeg since records began in 1872.

The warm weather has been persistent for the past 3 weeks over southern MB with every day this month above normal so far. But changes are on the way. A storm system is expected to cross southern MB Sunday, which will draw in much cooler air Sunday into Monday on strong northwest winds. This will bring the first spell of below normal temperatures in over 3 weeks, with the risk of a widespread frost by Tuesday morning. The cool outbreak however should not be enough to offset this September finishing as the warmest September on record in Winnipeg as well as most of southern MB.

Tuesday, September 22, 2009

Fall arrives.. but summer hangs on through the end of the week

Fall officially arrived today at 4:18 pm CDT, but you wouldn't have known it as sunny warm weather prevailed over southern Manitoba today. And the fine late summer weather will continue the rest of the week with sunny skies and temperatures in the mid 20s.. some 10 degrees above normal for the end of September. Changes are coming though by this weekend as an intensifying storm system moves across Manitoba and drags colder air into the Prairies by Sunday along with some rainshowers. More typical fall like weather is expected to close out the last few days of September, which should finish as the warmest on record in Winnipeg, as well as over much of the Prairies.

Sunday, September 20, 2009

Summer in September!

This was the scene in Grand Beach yesterday as temperatures soared to the 30 degree mark over much of southern MB Saturday. People flocked to the beaches on the last official weekend of the summer of 2009, a summer that was plagued by rain and cool temperatures. Locals say this is the busiest they have ever seen Grand Beach in September.. thanks to some late summer weather that has persisted most of the month. Click here for the Free Press article on summer's last hurrah.

Friday, September 18, 2009

Last official weekend of summer to be summer-like!

It looks like Mother Nature is trying to make up for her abysmal performance this summer with a glorious stretch of sunny warm weather heading into the last official weekend of summer.  Temperatures have been above 25C all week long with sunshine, and the warm weather will continue through the weekend before a cold front moves through late Sunday.  Saturday will see temperatures rise to the 30 degree mark over much of southern MB, especially over western MB where temperatures of 32C are forecast.  Sunday will continue to be warm, with gusty southerly winds pushing temperature into the mid 20s before clouds approach in the afternoon and evening ahead of the advancing cold front. This front will usher in occasional showers Sunday night into Monday with a return to more seasonable temperatures in the upper teens. However, long range models are now indicating that the cooler weather will be short lived as above normal temperatures are forecast to return by mid to late week. This virtually ensures that September 2009 will likely go down as the warmest September on record in Winnipeg since records began in 1872.  After 9 consecutive months of below normal temperatures, it’s the least we deserve!

Monday, September 14, 2009

Summer in September continues.. cooler weather next week

With a high of 27C this afternoon, today marked the tenth day of 25C or greater temperatures in Winnipeg so far this month.. matching the total number of 25C days recorded all of July. And it looks like we'll add a few more 25C days this week as the summer-like weather continues over southern MB with sunny skies and well above normal temperatures through Wednesday. There will be a brief cooldown Thursday into Friday as a backdoor cold front tries to push cooler air into southern MB. However, windy and warmer conditions will return this weekend with gusty southerly winds pushing us back into the mid to upper 20s. Long range models are indicating a change to cooler weather by next Monday as we approach the official first day of fall on Sept 22nd. In the meantime, enjoy the summer weather denied to us the past 3 months!

Friday, September 11, 2009

Drier weekend.. with above normal temperatures continuing next week!

Today's wet weather will give way to drier conditions for the weekend.. with temperatures remaining above normal for this time of year. Saturday will see partly cloudy skies with the chance of a stray shower, with highs in the low 20s. Sunday is looking very nice with sunshine , light winds, and high temperatures climbing into the mid 20s. Warm dry weather is expected for the first part of the week with highs in the mid to upper 20s, with a chance of some showers and slightly cooler conditions by Wednesday or Thursday. Still.. temperatures are expected to remain above normal through next weekend as the summery September of 2009 continues.

Thursday, September 10, 2009

Showers/thunderstorms developing late today into tonight.. more rain Friday

It will be another warm day today over southern MB with sunshine and temperatures near 27C this afternoon. A system moving into North Dakota this afternoon into this evening will trigger a few showers and thunderstorms.. mainly over North Dakota with some of the activity spreading into southern MB this evening into tonight. There is a slight risk of severe thunderstorms mainly south of the border where low level moisture will be more favourable for stronger storms. The weather system will slowly move across southern MB on Friday bringing more widespread showers over southern MB.. with 5-15 mm of rain possible over most areas. Some leftover showers on Saturday will give way to dry weather by Sunday.. with temperatures still remaining above normal into next week.

Sunday, September 06, 2009

Showers and thunderstorms Monday night into Tuesday.. locally heavy rain possible

Our stretch of dry warm weather will come to end Monday night into Tuesday as a slow moving cold front crosses southern MB. This front will trigger a band of showers and thunderstorms that will move into southwest MB by Monday evening, reaching the Red River valley overnight Monday into Tuesday morning. In general, most localities in southern MB should be seeing 10-20 mm of rain Monday night through Tuesday as this front crosses through. However, models are indicating that some of the rainfall could be heavy, with local rainfall amounts of 50 mm or more possible especially across SW MB into the Interlake area. The showers are expected to move east of the RRV Tuesday evening, with drier and slightly cooler weather for the rest of the week.

Friday, September 04, 2009

Summer like weekend.. cold front expected late Monday

It looks like Mother Nature is making up for her prolonged memory lapse this summer, with a nice warm finish to the summer holidays this weekend. The warm weather of the past few days will continue today and through the holiday weekend with temperatures in the upper 20s, possibly hitting 30C Saturday and Sunday. Labour Day Monday should continue to see warm temperatures, but a cold front is expected to push through late Monday into Monday night, triggering a few showers and thunderstorms as it crosses southern MB. The unsettled weather is expected to move out Tuesday with drier and slighly cooler weather as the kids head back to school. Long range guidance is indicating above normal temperatures returning by mid September.

Tuesday, September 01, 2009

Cool August ends 7th coolest summer on record

August was another cooler than normal month in Winnipeg.. the 9th consecutive month below normal. The average temperature for the month at YWG airport was 17.3C, or 1.2C below the normal August average of 18.5C. This comes on top of a very cool July (16.5C) and cool June (15.6C), with a 3 month summer average of only 16.5C, or nearly 2C below the normal summer average of 18.3C. This puts it just behind the summers of 1985 and 1883 as the 7th coolest summer in Winnipeg since records began in 1873.

Looking at the 3 month temperature graph for the "summer" of 2009, one can see the only warmth was a 2 week stretch in June and a 4 day hot spell in mid August (the 33C reading on Aug 27th is erroneous) Cool weather dominated most of the summer, especially July which did not break the 30C mark.

August now marks the 9th consecutive month below normal in Winnipeg.. the longest such streak since another 9 month stretch between Dec 1949 and August 1950.

Top 10 Coolest summers in Winnipeg (records began 1873)

YEAR Jun
Jul Aug AVG (C)
2004 14.1
18.2 14.3 15.5
1992 14.9
15.9 16.4 15.7
1885 15.0
18.0 15.2 16.1
1891 15.9
16.2 16.4 16.2
1968 15.4
17.6 15.5 16.2
1895 14.8
17.7 16.4 16.3
1985 14.0
18.8 16.3 16.4
1883 16.2
16.8 16.3 16.4
2009 15.6
16.5 17.3 16.5
1950 15.1
18.2 16.5 16.6
1884 18.3
15.4 16.1 16.6

NORMALS 17.0C 19.5C 18.5C summer: 18.3C

Saturday, August 29, 2009

Nice week ahead!

Looks like we could be seeing the nicest stretch of weather of the summer this upcoming week! Models are indicating an upper ridge building over the Prairies which will block any weather systems from moving into southern MB over the next few days. This will bring plenty of sunshine with high temperatures in the mid 20s through mid week.. which is actually a little ABOVE normal for a change(now 22c) The upper ridge will flatten a bit by mid week then rebound again for the end of the week into next weekend.. bringing more dry weather and warm temperatures. At this point, models are indicating the next significant threat of rain won't be until Labour Day.. so it will be a good stretch of dry weather to finally start drying up some of those water logged fields over southern MB. We need it.

Friday, August 28, 2009

Rob's Obs updating again

Greetings all! I'm back from holidays after 4 glorious weeks in sunny Italy. I've been blissfully unaware about the weather in southern MB over the past month, but I'm sure I experienced more summer weather in the past 4 weeks than the past 2 years in Winnipeg!

My website has been updated with weather data from my weather station in Charleswood, and I'll try to get the blog going again in the next few days.

Sunday, August 16, 2009

New post

New post for updated comments on latest weather.

Sunday, August 02, 2009

New month... Same story

Cool weather continues after third coolest July. Winnipeg waits while BC burns...

Saturday, July 25, 2009

Cool week to end cool month..

After near seasonal temperatures this weekend, another spell of below normal temperatures will be ushered into southern MB Monday, which will continue through the end of the month. High temperatures for the upcoming week are forecast to remain around 20C each day.. a good 5-6 degrees below normal for late July. This will ensure that July will end up cooler than normal in Winnipeg and southern MB.. making it the 8th consecutive month with mean temperatures below normal. Such a streak has happened only twice before in Winnipeg since 1971.. from Nov 1978 to June 1979, and from Oct 1995 to May 1996. Meanwhile, a huge upper ridge building over BC will maintain hot dry conditions over the province with temperatures of 35-40C through the upcoming week.

Monday, July 20, 2009

Still no hot weather in sight..

Hot summer weather continues to elude much of central Canada including the eastern Prairies as a strong upper ridge of high pressure persists over western Canada producing a northwest flow of cooler air for us. The result has been consistently below normal temperatures this month over southern MB with hot weather confined to western Canada, including the Okanagan interior of BC where forest fires are currently raging. (see 30 day temperature graph for YWG)

Not much change is expected for the rest of the month with the upper ridge expected to persist over BC (see attached 500 mb GFS prog for Friday) maintaining warm temperatures out west with near to below temperatures over the eastern Prairies. Although the absence of hot humid weather is a disappointment for beach and cottage goers in southern MB, the weather has been comfortable for most residents with the benefit of little or no need of air conditioning. As of July 19th, the mean monthly temperature in Winnipeg was 15.8C, putting it on pace for one of the coolest July's on record in the city since records began in 1872. The top two coolest Julys in Winnipeg were 1884 (15.4C) and 1992 (15.9C) Both those years followed major volcanic eruptions the previous summer (Krakatoa in 1883, and Pinatubo in 1991)

Thursday, July 16, 2009

Fall like weather to give way to nice weekend..

It’s a cool wet July morning out there with overcast skies, rain and temperatures only around 9C.. making it feel more like fall than mid summer.  A low pressure system over northern Ontario is bringing a gusty northwest flow of unseasonably cool air over southern MB today, along with occasional rain and drizzle. The air is even cool enough to generate enhanced bands of lake effect rainshowers to the southeast of Lakes Manitoba and Winnipeg today. The clouds and rain will keep temperatures only in the low teens at best today.. some 10-15 degrees below the normal high of 27C for mid July, the warmest time of the year in southern MB. Cloudy cool weather will persist tonight into Friday morning before skies begin to clear out by afternoon or evening as a ridge of high pressure over Saskatchewan builds into the province. This ridge will bring a much nicer weekend for us with sunny skies and more seasonable temperatures in the mid 20s.

Wednesday, July 15, 2009

Heavy rain swamps Winnipeg.. again..

For the second time in five days, thunderstorms brought heavy rainfall to Winnipeg, with particularly heavy amounts over the west end. The heavy rain swamped drainage systems, and led to extensive street flooding and waterlogged properties in west Winnipeg (see photo here of Buckle Drive in Charleswood). Last evening, heavy downpours began around 6:15 pm in Charleswood, and continued through 8 pm. At my site, I recorded 42 mm during the evening downpour (peak rainfall intensity 155 mm/hr) , on top of the 20 mm that fell with showers earlier in the day, for a daily rainfall of over 60 mm. Winnipeg airport recorded 45 mm yesterday, with 26 mm falling during the evening downpour. This comes on the heels of a heavy downpour last Thursday that dumped over 50 mm at my site (35 mm at the airport) Scattered showers will persist today across southern MB, but amounts will be light. Thankfully, a trend to drier and warmer weather is forecast over southern MB by the end of the weekend into next week.

Sunday, July 12, 2009

Nice today and Monday.. more showers/tstorms Tuesday and Wednesday

We've got some nice weather to enjoy today and tomorrow with sunshine, light winds and temperatures in the low to mid 20s. Things will get more unsettled Tuesday as another storm system pushes into the Northern Plains bringing a band of showers and thunderstorms into southern MB by Tuesday morning. Conditions are favourable for some severe thunderstorms to develop over Montana and western ND Monday evening, pushing into southern MB as a band of locally heavy thunderstorms overnight Monday into Tuesday morning. Models are indicating the potential for locally heavy rainfall with these storms over portions of southern MB overnight Monday into Tuesday morning, with local amounts of 30-50 mm possible. Additional showers and thunderstorms are likely Tuesday afternoon with
more showers expected Wednesday across southern MB as the storm system moves east.

Thursday, July 09, 2009

Thunderstorms with torrential rain hit Winnipeg

A line of intense thunderstorms moved through Winnipeg Thursday morning between 9 and 10 am bringing torrential rain and pea size hail. At my site in Charleswood, my weather station recorded 48 mm of rain in about 45 minutes.. with a peak rainfall rate of 457 mm/hr at 9:41 am.. the heaviest rainfall intensity my station has recorded since it was set up in 2001. The extreme rainfall led to many problems in the city including flooded underpasses, downed power lines and water damage to the Victoria General hospital.

Tuesday, July 07, 2009

Severe thunderstorms, heavy rain possible Wednesday night

A storm system developing over Montana will track into the Dakotas on Wednesday, bringing an outbreak of severe thunderstorms over western and central North Dakota by late Wednesday. These storms will have the potential to bring large hail and damaging winds, with a few tornadoes possible. The strongest storms are expected in North Dakota, however a few severe thunderstorms are possible across far southern and southwest MB Wednesday evening with large hail and damaging winds as the main threat. Thunderstorms will continue to spread over all of southern MB Wednesday evening, bringing mainly heavy rain Wednesday night into Thursday morning with local amounts of 25 to 50 mm possible. Stay tuned on this developing severe weather situation with updates from NWS Grand Forks, SPC, EC and of course, Rob's Obs!

Monday, July 06, 2009

Thunderstorm tracks over east Winnipeg

Here's a great webcam shot of the thunderstorm cell passing over the east end of the city. Temperature dropped to 13C with heavy rain in the east, while the west end of the city didn't get a drop, but gusty outflow winds dropped the temperature from 24 to 19C in 20 minutes. East St Paul reported up to 21 mm of rain with the cell with pea size hail in Transcona.

New website for Rob's Obs

Well, after the problems I was having with the FTP server at Shaw, I decided to post a new website for Rob’s Obs. The former Rob’s Obs website address at http://members.shaw.ca/wpgwx/robsobs/home.htm will no longer be valid. That site will redirect you to my new site at www.robsobs.ca This new site is a total redesign that’s been in the works for a few months, but I thought I’d launch it now given the FTP problems I was having with my old site. The new site has a cleaner, more professional look, and is faster to load than the old one with no annoying pop ups ( I hope!). And my weather station is updating data to the site again. So we’re back in business. Hopefully you find this new design an improvement over the old one.

Also note that jpg images from my site now have a “no_cache” added to the directory.. so if you have any links to Rob’s Obs .jpg images, be sure to add /no_cache after /robsobs to get the valid images.

Thursday, July 02, 2009

June 2009 weather stats for Winnipeg

After an unseasonably cool first half of the month, temperatures finally warmed to above normal values for the latter half of June as summerlike weather finally made an appearance over southern Manitoba. The warm weather however was not enough to offset the cool start, and as a result, June finished almost 1.5C below normal, with a monthly mean temperature of 15.6C at Winnipeg airport. This made June the 7th consecutive month with mean temperatures below normal (December 2008 to June 2009). Although significant this is not record breaking. Since 1971, there have been four other periods with 7 consecutive months of below normal monthly mean temperatures in Winnipeg, namely...

November 1973 to May 1974

June 1985 to December 1985

May 1993 to November 1993

November 1996 to May 1997

There were also two periods with 8 consecutive months below normal

November 1978 to June 1979

October 1995 to May 1996

The month was marked by an exceptionally late freeze on June 6th.. with a record low of -4.6C at Winnipeg airport.. the coldest June temperature ever at the airport since 1938, and the second coldest June temperature in Winnipeg since June 1 1888 (-6.1C) Downtown Winnipeg escaped the freeze with no frost reported at the Forks weather station. 

PRECIPITATION

A strong storm system on June 26-27th brought heavy rainfall and strong winds to southeast Manitoba with over 100 mm of rain in areas east and southeast of Lake Winnipeg. This system brought heavy rainfall to eastern sections of Winnipeg with 75 mm reported while western areas, including the airport, had 35 mm. Other than this system precipitation was generally light in June with a lack of showers and thunderstorms. As a result, precipitation varied greatly across the city in June. Whereas the Airport only had 61.5 mm, the downtown station at The Forks had 82.8 mm and according to the rain gauge network operated by the City of Winnipeg, there was over 90 mm in the many areas of Winnipeg east of the Red River. Normal June rainfall in Winnipeg is 90 mm. 

Sunday, June 28, 2009

Heavy rains soak southern /eastern MB


A strong storm system brought heavy rainfall across southern MB June 26-27th. The storm began as showers and thunderstorms Friday the 26th with heaviest amounts across the southern RRV and southeast MB. The system then wound up as an intense low pressure system over northwest Ontario on the 27th, bringing a soaking wind-driven rain over eastern MB, with the heaviest rainfall over the Interlake and Whiteshell areas. Here is a summary of rainfall amounts over the past 2 days.

Official observations (EC)

Location storm total

Brandon - 11.0 mm
Carberry - 13.2 mm
Oakpoint - 24.6 mm
Pilot Mound - 27.8 mm
Winnipeg - airport - 31.2 mm
Portage la Prairie - 33.8 mm
Delta marsh - 35.2 mm
Deerwood - 36.4 mm
Sprague - 40.6 mm
Morden - 47.0 mm
Fisher Branch - 48.2 mm
Winnipeg - the forks- 50.6 mm
Gimli - 67.7 mm
Gretna - 72.2 mm
Carman - 75.2 mm
Great Falls - 92.0 mm
Pinawa - 94.6 mm

Unofficial observations

Location storm total

Altona - 85.0 mm
Arborg - 75.0 mm
Dugald - 78.4 mm
Elm Creek - 62.0 mm
Landmark - 99.8 mm
Letellier - 76.4 mm
Marchand - 92.7 mm
Morris - 85.2 mm
Portage la Prairie - 47.2 mm
Selkirk - 84.4 mm
St. Pierre - 101.8 mm
Starbuck - 36.4 mm
Steinbach - 82.0 mm
Teulon - 67.8 mm
Treherne - 55.8 mm
Winnipeg north - 59.0 mm
Winnipeg west - 35.0 mm
Winnipeg south - 55.0 mm
Winnipeg southwest - 38.8 mm
Woodlands - 48.8 mm

Thursday, June 25, 2009

Thunderstorms and heavy rain possible Friday night

A trough of low pressure over Saskatchewan will be advancing towards southern Manitoba Friday into Friday night. Southerly winds ahead of the trough will bring a warm and increasingly humid airmass over southern MB during the day, with thunderstorms developing by late afternoon or evening. The storms may generate heavy rainfall over the Red River valley Friday night into Saturday morning with rainfall amounts of 20-30 mm likely, with 50 mm or more possible in some areas. Some storms may be severe with large hail and damaging winds. Cooler and unsettled weather will follow on Saturday before a drying trend Saturday night into Sunday.

Sunday, June 21, 2009

Sunny warm morning for Manitoba marathon

Sunny and warm weather conditions prevailed today for this year’s Manitoba Marathon, coinciding with the first official day of summer  The race started at 7 am with temperatures at a comfortable 19c. However, the strong sun quickly warmed up temperatures to 24c by 9 am and 27c by 10:30 am with southerly breeze of 20 to 25 km/h. Humidity levels were moderate, with dewpoints around 15c.  The conditions were a marked change from the weeks of below normal temperatures leading up to the marathon.

Thursday, June 18, 2009

Locally severe thunderstorms possible this afternoon

Hot and humid weather over southern MB today along with an approaching trough of low pressure will set the stage for the development of some strong thunderstorms this afternoon.. some of which may reach severe limits. A severe thunderstorm is defined as a thunderstorm producing one or more of the following..

- hail of 2 cm or more (nickel size or greater),
- wind gusts of 90 km/h or more
- rainfall of 50 mm in one hour or less, or 75 mm within 3 hours
- tornadoes

Today's thunderstorms will likely be slow moving storms given a weak flow aloft, so heavy rainfall will be the main threat, although some storms could produce nickle to quarter size hail given the instability levels. Storms are expected to develop over western MB this afternoon ahead of the low pressure trough, and move into the Red River valley by evening before dissipating tonight. Stay tuned for updates and possible watches and warnings on today's weather..