Tuesday, November 27, 2012

Cold and dry next couple of days.. then snow chances and temperatures increase late week into weekend

Cold high pressure building over the Prairies today will bring cold but snowfree conditions today into Thursday over southern Manitoba. Temperatures will be several degrees below normal with highs around minus 10, and lows tonight near -20C, although Wednesday will likely moderate briefly to around -7c.  By Thursday evening, a wave of snow will be pushing across southern Manitoba ahead of a warm front that will be moving in from the west. This front will usher in milder air for Friday into the weekend, with temperatures climbing towards the freezing mark. Additional snow is possible Friday night into Saturday as another wave of precipitation pushes across southern Manitoba.   Long range guidance is hinting at a possible stronger storm system affecting southern  MB Monday bringing in a flow of milder air across the RRV with even some rain possible.    

24 comments:

  1. Rob,

    you mentioned the possibility of a more stronger storm by Monday. Does look anything like the major storm that occured back on November 10th?

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  2. No, the system for next Monday will still be a clipper style system, just a little stronger, and to our west initially which would draw warmer air over us. Turning colder on the backside with snow possible Monday night into Tuesday. At least, that's what the long range models are hinting at right now.. there will likely by a few changes in opinion before then given the highly variable pattern that is shaping up.

    Nov 10th was a more classic "Colorado low" system tracking into northern Minnesota which traditionally are bigger snow producers over southern MB.

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  3. CYWG's still calling it 14SM visibility but here in Westwood we're down to 1/4 mile vis in fog?!

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  4. Don't see any fog in south end right now

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  5. Weather Network is forcasting 20 cm of snow for Monday!! Yikes. Say it isn't so Rob!!

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  6. XWL is back up according to EC's site.

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  7. Re: Monday forecast

    Monday looking very tricky at this point in terms of precipiation amounts and phase. GFS has storm tracking through Dakotas with mixed precip changing to snow over southern MB.. although bulk of snow falls through interlake. GLB and Euro are warmer on the storm, with above freezing temps Monday over RRV and rain possible. 20 cm of snow for Winnipeg Monday seems unlikely at this point.. but we'll see how the models trend on this next system.

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  8. By the way, just got notice that EC radars on Weatheroffice will be switching over to snow rates on Monday Dec 3rd (just as the rain starts pushing into southern MB :)

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  9. Looks like area of snow will be pushing into west central Manitoba Thursday afternoon reaching Winnipeg/northern RRV by evening. Swath of 3-6 cm of snow expected mainly north of Winnipeg, with a couple cm possible for the city.

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  10. Rob,

    Various sources show both the phase and intensity of precip on their radar maps, even for Canadian radars. I can appreciate the need to optimize the beam for the dominant precip phase (snow or rain), but isn't it possible for EC to process the data to show both intensity and phase on their products?

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  11. Rob I know you work with EC and maybe can't comment but should we not expect better forecasting then we currently get. The fact that we only have computer forecasting 2 days out seems a little sloppy. For example even this morning thursday's snow forecast there was no mention of snow for thursday even though all of the other weather orgs were already calling for something. Does EC do this same style of forecasting in every city in Canada or is Winnipeg an exception? EC is the primary forecaster in Canada and you would think they would be more diligent then just using computer forecasting less then 2 days out. I am not trying to start a war but it seems a little strange especially when your dealing with large urban centers

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  12. Daryl..

    For better or worse, EC decided a while ago they would invest most of their resources to concentrate on weather in the next 24 to 48 hours. Beyond that time, they've decided to automate most of their forecast production.. due to limited resources and the greater difficulty to add value in the medium to long term. The thinking is that most people will be impacted more by weather in the short term than later on.

    Automated forecasts are only as good as the models that drive them, and the programming that produces them. In EC's case, the Day 3-5 forecasts are based on one model, the Canadian GLB model, which is a fairly good medium range model, but not the best. Ensembles would likely be a better option, and would at least minimize day to day variability. Add to that some programming oddities (like not mentioning precip if it falls at night), then you'll have cases where things are missed.

    This is why I run this blog.. it's to point out those deficiencies, and to add some insight into what may happen. Hopefully, highlighting these issues can lead to changes that will improve EC medium range forecasts in the future.

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  13. Anonymous

    Re: EC Radar

    EC has very limited capabilities when it comes to displaying radar. They give you the basic radar display, and that's about it. They have 1.0 km cappi for snow images and 1.5 km cappi for rain, but only choose to display one or the other. Several other website radar sources will use EC radar data and provide much more useful displays, including better background geography and zoom functions, as well as phase indications. Frankly, I find EC radar display on Weatheroffice lacking compared to what could be provided.

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  14. New guidance this afternoon showing about 3-5 cm of snow for Winnipeg late Thursday, most of it falling between 6 pm and midnight.

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  15. Rob,

    You mentioned possible 3-5 CM with tomorrow evening's system. Earlier in the week there was some indication of snow Saturday as well.

    Is that still the case?

    What are the latest indications for Monday's system in the RRV?

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  16. Daryl,

    There's a really good writeup of Project Phoenix, which was basically a 'competition' between human and fully automated forecast here at EC.

    https://ams.confex.com/ams/pdfpapers/122657.pdf

    They basically used the results (which are somewhat ambiguous) as justification for fully automating the extended forecast, from my understanding.

    Also remember these forecasters are responsible for much of western and arctic Canada, while your TV and radio weather personality has hours to spend every day simply looking at the Winnipeg forecast.

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  17. Thanks Rob for the info

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  18. Anonymous..

    Saturday snow chances look better north of Winnipeg with a few cm possible as another weak system passes though. Further south Winnipeg may get some mixed precipitation or light snow, but minimal amounts.

    Stronger clipper moves across southern MB Sunday night into Monday with heavier snow across the western parklands and interlake areas. Winnipeg/RRV will be in warm sector ahead of the system initially with some rain or freezing rain possible Sunday night into early Monday, changing to snow during the day Monday into Monday night on backside of system with colder northwest winds developing. Perhaps 5 cm or so here.. heavier amounts north of the city through the Interlake. Kind of a messy variable pattern setting up over the next few days with precip timing and phase issues.

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  19. Thanks Garth

    I haven't read it yet but it looks interesting I will read it tomorrow.

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  20. Interesting reading about the Phoenix project. As a forecaster at NWS Grand Forks I spent a week up at the Winnipeg office as part of a forecaster exchange program. I sat with the lead each day and observed the tools of what the Winnipeg office had and how their forecast breakup was done.

    It does seem the NWS follows Env Canada about 10 years....as over the past couple of years we have gone to a more automated populate our gridded database with an ALL Blend procedure for days 4-7. This tool was developed to take what was in the forecast currently and then blend it all the available operational models (GFS, ECMWF and GEM). We at the NWS run this tool twice each day (1230 am and 1230 pm CST) to populate the day 4-7 gridds. The thought is to focus on days 1-3.

    One thing though I dont want to see is a trend toward closing smaller offices and going to more regional ones. There was a test brought up a couple years ago called the CONOPS plan which was like that....having a regional forecast center and then keeping the local offices for local warnings, etc. That never got off the ground as weather is very much on the minds of most Americans and many local congressmen and women in Washington love to keep their own office around in their district. But with the U.S. budget troubles who knows.

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  21. Light snow starting to spread into western MB this morning.. should be into Winnipeg by the drive home. Still looking on track for a general 2-5 cm for us, mainly between 6 pm and midnight.. with 5-8 cm possible over Riding Mtn area.

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  22. Hey....wouldnt mind it if you would share some of your snow south a bit.

    Doesnt look like any real snow down here Grand Forks for a while. But hopefully can keep what we got...1-2 inches on the ground.

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  23. Hi Dan. I'm not sure how much you know but I was wondering what the short term job prospects for meteorologists/weather specialists looked like in the US? I know there are plenty of opportunities in the governmental sector but are there opportunities in the private sector as well?

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  24. About job prospects in the U.S.....aactually for meteorologists the competition is very very tough and many folks graduating now in meteorology cannot find jobs in the field. The NWS hiring has many more applicants than positions....private sector more varied.

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