Wednesday, February 14, 2007

The end is near!

..The end of the cold snap that is! The Arctic vortex that has held Southern MB in its grip for the past two to three weeks is finally showing signs of breaking down by the weekend. As a result temperatures will finally climb to normal and even above normal values over the next few days, and should remain above normal next week. In the meantime, we have one more cold night to endure tonight as temperatures once again fall to the minus 30 degree mark at the airport. The moderating trend will begin tomorrow as brisk southerly winds start to push out the Arctic airmass, although wind chills will still make for a cold day. Milder conditions are expected on Friday with highs climbing into the minus single digits for the first time since January 26th. A brief cooldown is expected on Saturday but then gusty southerly winds will begin bringing milder air again for Sunday into Monday. Currently, the forecast high for Sunday is +1 which is likely a little optimistic given that southerly winds are forecast, which tends to trap colder air in the Red River valley. Nonetheless the trend towards milder conditions is forecast through all of next week, which will be a welcome change for cold weary Manitobans!


  1. Wow.. now EC is saying +4C for Sunday while Accuweather is saying -16!! I have a feeling the true answer will be somewhere in between!

    Forget the +4.. that just ain't gonna happen. We have a storm system moving in from SK that will move across Southern MB on Sunday bringing snow through the interlake. For Winnipeg to hit +4, the low would have to track across central or northern MB, and we would have to get into a westerly flow of Pacific air tapping milder air from the west. None of the models show this happening. Instead the low is supposed to track over us, or to our south which would keep the milder air to our south and west. For Winnipeg, this means east to southeast winds ahead of the storm will tap colder air from a departing Arctic ridge, which will keep temperatures down.. probably around minus 5 to minus 10 in the afternoon.

    Of course, things can change, but based on current models, and that cold air usually wins in these cases.. I wouldn't be counting on any thaw for Sunday.

  2. There are big timing differences between american (GFS) and canadian (GEM) models in handling the last piece of arctic air.

    The GFS has an arctic ridge over southwestern Manitoba on Sunday morning and brings down very cold air at 850 mb. GEM shoves all the cold air into Quebec and Ontario very quickly. This does not seem realistic. Like you said, a compromise between the two solutions is the most likely outcome.

    Btw...The only info I can find about the other airport station, 'XWG' is from this website:
    It shows a graph of the latest temperature trends at the bottom. I have no idea where they get the data from.


  3. Dan..

    I think XWG is the Winnipeg "A" CS climate station available on the EC climate website at..


    It also has SOG measurements from the sonic snow sensor.

    A look at the low temperatures shows that the XWG site is even a tad colder than the YWG site!

  4. EC has dropped it's Sunday forecast high from +4C to -2, while Accuweather has raised their -16C to -8. Looks like we're converging towards a -5C solution!

  5. Forecast high for Sunday is now -7c. So much for +4!

  6. Thanks for the link Rob...yeah it looks like it gets even colder at the other site...

    As of 8 PM Sunday we are only at -9 C... but still rising. It looks like the low will track south of Winnipeg so we will not go above zero like it was in Regina today :-(

    Looks interesting for end of the week as flow turns southwest ahead of a big upper trough. A colorado low is a distinct possibility somewhere between Manitoba, Northwestern Ontario and Minnesota. But still too far out.