Sunday, May 02, 2010

Snowflurries tonight?

After 2 days of rain, colder air is starting to sweep into southern Manitoba behind this storm system. Light rain continues over the Red River valley, but further northwest, rain has changed to snow over western Manitoba where there has been some accumulations north of Dauphin (see image here from Wellman Lake in the Duck Mtns) Winnipeg can expect to see additional light rain today into tonight with another 5 mm possible, but don't be surprised to see some flakes of wet snow overnight into Monday morning as colder air moves in. Accumulations are not expected here in the city, but there could be some areas that see a covering of slushy snow tonight into Monday morning. Another storm system tracking through the Prairies early this week is expected to bring more rain to southern Manitoba Tuesday, with wet snow possible again Tuesday night into Wednesday as another shot of cold air sweeps in. Welcome to May!


  1. As it stands now there is a fair chance of snow on the backside of Wednesday system!!

    Some fairly cold air is set to settle in with the departing low!

    Accumulating snow????

  2. Wow, sunny outside earlier, but then I go downstairs and 5 minutes later, it's pouring rain! 2 mm in minutes.

  3. The winds have picked up quite a bit this afternoon...most likely gonna draw in some colder air tonight for some snow!!!

  4. At this point looks like the bulk of precip with the next system will fall over areas north of Winnipeg. We get a shot of warm advection precip Tuesday morning and the dry slotted during the day by the looks of it. More wraparound on Wednesday as mentioned.

    Pattern flips back to a decidedly winter-like configuration with vast upper trough covering most of Canada and sharp baroclinic zone suppressed well south across central plains. Attention turns to disturbance that begins dropping south from Gulf of Alaska by Fri May 7. Energy crashes onshore by May 9 and moves into four corners area forming Colorado Low.

    Potential is there for significant snowstorm somewhere over northern plains by May 10/11... for now it appears Manitoba will stay north of its effects like with almost all previous Colorado Lows this winter season.

  5. Snow in Brandon right now with visibility down to 3 km!

    Winnipeg temperature down to 2 c and falling fast so we still might get snow yet!

  6. The golf season is almost two months old and we finally have a sub par week ahead. ☁☹

  7. Rob!

    What is your take on this next system???

    Snow or rain????
    How strong will the winds be??

  8. Are we in for these winds tonight or tomorrow??
    NWS High Wind Watch

  9. WHOA!!!

    Winter storm Watch issued for area around Dauphin and Gladstone!

  10. Jim...

    No those warning criteria westerly winds will occur on the sothern flank of the system. Low passees over us so we will have relatively slack flow. Even in cases where strong gradient moves over S Manitoba, the strongest winds with a westerly component tend to blow over top of the valley. This is bad in winter when we want to mix down warmer air but an advantage in situations like these.

    Band of warm advection precip moves in around early afternoon by the looks of things. Main precip band should lift NE of Winnipeg by evening as dry slot tries to work in. Deformation band rotates back in early Wednesday at which time wet snow will start to mix in. However given warm ground and anticipated light nature of precip... would be surprised if we got much accumulation here.

    GFS still showing one or possibly two Colorado lows taking aim at Northern Plains next week. Regional wetaher offices in US still downplaying system somewhat.. apperently leaning on National/HPC guidance which is heavily influenced by ECMWF model.

    THREE HILLS..............106 KM/H
    BASSANO..................106 KM/H
    HUSSAR................... 96 KM/H
    POLLOCKVILLE............. 93 KM/H
    STRATHMORE............... 91 KM/H
    BIESEKER................. 89 KM/H
    CALGARY INTL AIRPORT..... 85 KM/H Initially, 80km with 100km Gusts

    NWS Wind Advisory/Warnings for North Dakota coming from AB and SASK were issued yesterday early afternoon. Todays Environment Canada Weather Warning

    What criteria are used when gale force or +100km winds are expected or imminent.

  12. Daniel

    Thanks for your answer yesterday... One of these days I'll learn how to edit

  13. Precip band having a tough time working NE. Low levels appear to be sufficiently moist but large scale lift hangin up over N Dakota. RUC depicts forcing to finally move over Winnipeg around 7 PM.. but also weakens it. Models like GFS and NAM show precip band maintaining its intensity overnite. Looks to me as though heaviest band will stall out (of course) over southern RRV. Precip amounts for Winnipeg really tricky.. will have to see how far north band can get over next few hours before coming to a halt.

    Next upper disturbance appears to track too far south with jet stream suppressed over cnetral plains... subzero 850 hPa temps could spell wet snow for places like southern N Dakota and central Minnesota Friday morning.

    Pattern becomes more amplified as yet another disturbances comes onshore early next week (May 10). Deep trough is carved out over SW USA and a ridge from upper high over Florida pokes up towards Great Lakes. This system will therfore be deflected towards the Northern Plains and Upper Midwest. Potential there for SE Manitoba and even RRV to be brushed with precip by middle of next week.

  14. Winnipeg Forecast now changed to
    20 -30 mm of rain!

  15. As of 8:45 pm Rob has 14 mm of rain!

    20 -30 mm storm total seems reasonable!

  16. Are we seeing a break from the rain now? Rain seems to be moving away. Only 11 mm i've measured so far, south end. First time I've seen in very long time, more rain at Rob's place than here. =Þ

  17. Yeah, a real soaker out there.. my poor daughter had to play soccer in that slop. General amounts of 10-15 mm so far tonight across the city.. but look at Winkler.. 43 mm today according to the Manitoba ag-wx site there!

  18. Convection blossoming over NW Ontario on nose of LLJ and across 850 hPa warm front. Models like RUC hinting that some of this may wrap back towards Winnipeg area (degrading to stratiform precip) until 2-3 AM...

  19. 27 mm at my place since yesterday afternoon. 65 mm since Thursday. I think drought concerns have been alleviated for now..

  20. Next in series of disturbances already taking shape. Surface low will track from Texas panhandle to Windsor ON. However midlevel low (@ 700 and 850 hPa) tracking along N/S Dakota border will support inverted trough poking up into Northern Plains. Will precip be able to get pumped up into southern RRV overnite Thursday into Friday? 850 hPa temps and 1000-500 MB thickness support snow. However given probable lite nature of precip, shallow above freezing layer may be enough to keep things as a drizzle/snow mix with no accumulation on warm, wet ground. Best chance for accumulation would be further south where forcing is and corresponding precip intensity will be stronger. What is your take Rob?

  21. Yeah, looks like best chance for accumulating snow will be over western and SW North Dakota with this next system.. where pcpn type has a better chance of falling as snow due to higher elevation, greater pcpn intensity, and pcpn occurring at night. Sure glad all this May snow is missing us!

  22. April was so warm and dry I thought that maybe this summer is gonna be a hot one!

    Now this horrible cold weather for the first part of May and it got me thinking
    This BETTER NOT be a repeat of last year!

  23. Daniel P, I've had the esact same concern the past few days. Was April a big tease or is this just a setback in a nice overall season. Rob, what do you think?

  24. Another rainfall event? Doesn't look too impressive, but any thoughts?

  25. After a nice dry weekend, things look a little more unsettled for the upcoming week. A weak system over southern SK Sunday will bring a chance of a few showers over southern MB for Monday, but nothing major. A stronger system is forecast to track through the Dakotas into Minnesota Tuesday with some rain from that system spreading into southern MB along an inverted trof. Again, nothing major expected for us as the bulk of the rain stays south of us, but we could see 5-10 mm out of it. Some lingering instability may give us a few more scattered showers Wednesday before warmer and drier weather moves in for the end of the week into next weekend.

  26. Rob!

    Have you ever heard of the term....


    If not, check out Dave and Justin's blog!

    I also think someone wants the day off to go storm chasing!!!!

  27. Our problem this week is we live too far South. See Churchill Mb for the next few days

  28. The last time we had 25 mm (1 in) of rain each week at the end of April and the beginning of May was the El Nino of 68-69.
    Although pcpn was similar each month from Nov to April this year has been significantly warmer.

  29. Yeah, Justin's getting a little excited about the tornado potential in Kansas tomorrow. Long tracked strong tornadoes possible, but "tornadopocalypse" conjurs images of swarms of F5 tornadoes destroying everything from Texas to North Dakota.. (not to be confused with "tornadomageddon" which is a massive tornado outbreak that ends the world as we know it)

    I think I'll stick with the more conservative "mdt risk" for now :) (which will likely upgraded to high risk) Whatever you call it, should be an interesting day for severe weather down in tornado alley Monday!

  30. lol yeah, tornadopocalypse is a little much hahaha...

    I do like tornadomageddon though!