Thursday, October 09, 2008

Thanksgiving weekend outlook

Cool and unsettled conditions will be the main story for the upcoming Thanksgiving weekend over southern MB. A sharp frontal boundary is forecast to develop across the Dakotas on Saturday before a storm system tracks across southern MB on Sunday, followed by windy and cooler conditions on Thanksgiving Monday. The details..

Saturday should be cloudy and cool across southern MB as the frontal boundary begins to set up across the eastern Dakotas into northern Minnesota. This boundary will be separating warmer and drier conditions to the east from cool and wet conditions to the west. An area of rain will develop along this frontal boundary over the Northern Plains and spread into southern MB Saturday afternoon and evening. Rain may become heavy at times Saturday night into Sunday morning, with thunderstorms possible, as a low pressure system develops over the western Dakotas and tries to spread warmer air into southern MB. Rain from this system will continue to spread to the north and west of Winnipeg on Sunday, so there may be a break from precipitation Sunday afternoon over the Red River valley and SE Manitoba. Sunday night, a cold front from the low will sweep across Southern MB, bringing windy and cooler conditions on Monday, with clouds and a chance of showers.

My holiday weekend forecast for Winnipeg. Note that the timing of the precipitation will be subject to change based on how these systems develop over the next day or two. At this time, this is what the models are saying.. (updated Saturday morning)

Saturday..Cloudy and cool. Chance of showers this afternoon. High 9.
Saturday night..Periods of rain developing. Low 7.
Sunday..Rain heavy at times tapering off in the afternoon. Chance of a thunderstorm. Total rainfall amounts 15-25 mm. High 14.
Sunday night..Chance of showers. Low 5.
Monday..Mostly cloudy, breezy, cooler. Chance of a shower. High 8.

9 comments:

  1. Environment Canada is calling a forecast high of 10 on Saturday
    And then 18 on Sunday!
    I'm sure 18 C is just to high!
    That would be quite the warm front to boost us to 18 C!

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  2. The GLB model, which is used to produce EC's extended forecasts out of Montreal, is showing the low pressure system moving west of Winnipeg on Sunday and putting us into the warm sector giving us that high of 18C. The GLB model is an outlier with this solution... most other models are keeping the warm air to the southeast of Winnipeg, with highs more in the 10-14C range here. The GLB model may be right.. but right now, the consensus is that Winnipeg won't get into the warm sector Sunday.

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  3. Winter Storm Watches posted for much of Montana, Wyoming, and western Dakotas for snowfall of 6-12 inches over the next few days. May be seeing similar messages for southern SK as this system moves north over the weekend.

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  4. That's looking like quite the storm brewing in the N. Central US! 1-2 feet of snow over Friday through Sunday is amazing - hopefully it's not that potent if/when it moves north and affects Saskatchewan for Thanksgiving weekend...

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  5. Things are looking better and better if you want a Snowstorm....
    that's if you live in southeastern Saskatwan
    Regina area might be the bulls-eye for the heavy snow!

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  6. Winter Storm watches now in effect for Montana and western ND right to the SK border. Interesting storm system developing over the weekend with pronounced differences in the way models are handling it. Best bet for accumulating snow in southern SK this weekend will be over higher elevations south and west of Moose Jaw through the Assiniboia, Swift Current and Cypress Hills areas. Models are hinting there may be enough warm air wrapping around from the east to gave a rain/wet snow mix to southeast SK keeping accumulations down in those areas.
    Nonetheless, snow still possible over SE SK including Regina.

    For us it'll be wet, rather than white. Sure wish I was in Southern Ontario this weekend enjoying those 25C temperatures and beautiful fall colours!

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  7. So much for that high of 18 C on Sunday!!!
    I should have know that was a little to high considering we going to get only up to 9 C today!

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  8. no winter storm warning, but a heavy snowfall warning has just been issued (11:30 CDT Saturday) for parts of southern SK. winter storm watches elsewhere.

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  9. Not surprisingly, latest REG model has backed off on bringing the warm front north of Winnipeg on Sunday, and is now agreeing with most other models keeping warm sector well southeast of us. As a result, Sunday's high has been dropped dramatically from 18C to 10C now as we stay north of the warm front and in the rain most of the day.

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