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.

33 comments:

  1. If we get even the slightest breeze any one of these days this week windchill readings will approach warning levels!!

    Saskatoon had a -40 C windchill this morning!!!!

    Don't you just love this weather Rob?????

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  2. A note about windchills..

    A windchill of -40 is considered to be a warning level ONLY if the accompanying windspeed is 13 km/h or greater, AND these conditions are expected to last for at least 3 hours. Officially, windchill is not considered significant if wind speeds are below 13 km/h.. so the forecast will not include them if wind speeds are expected to be lighter than this. Unfortunately, windchills are reported for ANY windspeed as long as the temperature is 0C or lower. This results in an inconsistency where windchills are being reported, but are not necessarily being mentioned in the forecast. Something to keep in mind over the next few days as we get down towards that -30C mark.

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  3. Can anyone tell me why Key Lake SK gets so cold all the time???

    They were the cold spot in Canada this morning and surely will be many more time this winter as they are every winter!!!!

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  4. Interesting to note the "milder" temperatures this afternoon over Winnipeg and the northern RRV with daytime highs of -14C or so.. along with some afternoon cumulus clouds. Compare this to the -20C readings over the southern RRV and to our southwest. Satellite photos show a lack of snowcover over Winnipeg and the northern RRV, with the darker ground allowing slightly warmer temperatures here than if we had a deeper snowcover. This snowpack will result in colder minimum temperatures of -30 to -35C tonight in areas to our south and west where the snowpack is deeper.

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  5. Any future possibilities for snow?.... Any?..

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  6. Jordan!

    Chances of snow look very slim in the next week!

    Thursday could be a few flurries!

    Saturday night could be some very light snow with a dusting possible with another shot of colder air coming in!!!

    After that it's a guess at to might what happen but you would think sooner or later Winnipeg and area's luck will run out!!

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  7. Good call on the temperatures for western Manitoba Rob!

    -30 to -35 this morning!

    So you think Winnipeg could see their first -30 C tonight????

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  8. Yes, I think Winnipeg airport will see its first -30C of the season Wednesday morning, with plenty of -30 to -35C readings to our west and southwest. Coldest readings of -35C should be near the SK border again. Areas to the southeast of Winnipeg will likely not get as cold tonight as they get some cloud and a little wind from that big storm system to our south.

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  9. Luckily winds are light with these cold temperatures so windchills are not a big concern right now. That won't be the case this weekend which is looking brutal for windchills. Another cold outbreak will be moving in with winds of 30 to 50 km/h likely producing warning criteria windchills of -40 to -50 across southern MB. Yikes!

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  10. Models are showing the potential for a warm-up towards the end of next week. Hopefully that is El Nino making a much needed appearance.

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  11. Latest MODIS satellite image from today shows MB lakes are almost completely frozen over (click on my name for image). Just a narrow area of open water over the north basin, with thinner ice over the south basins.. but pretty much ice covered. These lakes were wide open just 6 days ago! Always amazes me how fast these large bodies of water can freeze up.

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  12. Yeah our lakes are simply too shallow and our rivers are too sluggish to keep any open water well into winter. Its too bad really... if the lakes had larger coverage and were deeper they would significantly modify our cold, continental climate.

    Interesting to note the high thin cloud associated with sourthern system already reachinng Winnipeg - faster than models like NAM depict. The above model shows clouds above 500 hPa thickening up closer to midnite for us. I hope this coupled with the sparse snowcover will keep us from the dreaded -30 C mark tonite.

    The core of the cold air remains under the high pressure centre and deeper snowpack as has been noted already.. Regina struggling in the mid to upper minus twenties this afternoon.... yeesh.

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  13. I know it just started but I've had enough of this cold already. Daniel are you the cause of this. Ha

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  14. Well I was wishing for all of this cold air but now that's it here I'm having second thoughts!!!

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  15. It does look like Sunday into Sunday night when the winds are going to pick up and give us some very cold windchill values!

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  16. Whats the story with the snow on Saturday?

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  17. Latest models have eased up a bit on that next shot of arctic air pushing over us this weekend. Models now hinting that the core of the next Arctic push will stay north of us over northern MB this weekend (although we'll still be cold as we get a piece of it, possibly ushered in with a dusting to 1 cm of snow Saturday), while a secondary lobe of Arctic air drives down over Alberta and BC (GFS is most aggressive on this scenario with an insane -40C 850 core pile-driving down over the AB/BC border Sunday into Monday) This spawns a low over the northern US Rockies Sunday into Monday with a trof over the southern Prairies which eventually brings the next reinforcing shot of Arctic air over southern MB Monday into Tuesday. Latest GLB and GFS indicate we could see a few cm of snow Monday (2-5 cm?) with the passage of that trough followed by plunging temperatures and bitter windchills early next week. GFS had been advertising a warmup by mid December but it looks like they've backed off on that scenario.

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  18. Looks like around -29 C at YWG this morning. That lite WSW to WNW flow didn't do us any favors - allowing that cold air and strong inversion to ooze in from the snowpack out west.

    These extreme temps without appreciable snowcover will allow for greater frost penetration than would otherwise be the case... another counterintuitive consequence of global warming, just like the damage possibly caused from the sudden hard freeze in October after the record warm September.

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  19. Rob!

    If Winnipeg were not to get any more snow between now and Christmas would the current snowpack be enough to be classified as a white Christmas????

    I always thought there had to a certain depth to the snowpack to be a white Christmas!!!

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  20. TWN is trending a potential warmup next Thursday for 6 or 7 days at least.
    Does anyone see us flirting with positive numbers in & for a week?

    Last winter and spring IMMIA (If my memory is accurate) TWN often trended a warmup a week out that rarely occurred. However, it did give us hope.

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  21. After a sunny TWN Minus -1C Christmas eve (Dec 24th trend ) One might surmise the elimination of any lingering snow.

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  22. I would define a Green Christmas as a snowdepth with a trace or no snow on the ground. Right now, it looks like we have about 1 or 2 cm on the ground, so that would have to go by Christmas. Not sure that's going to happen given the cold weather for the next week at least, with a chance of some light snow on a couple of those days.

    As for that warmup in 7 days, GFS has been advertising this for awhile now.. I suppose they'll be right eventually. Long range ensembles are forecasting amplification of an upper ridge over BC which puts us in a northwest flow aloft.. which is not conducive to a rapid warmup this time of year.

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  23. Cold core with next Arctic outbreak moves over northern SK Friday into Saturday with a sub-474 dam thickness and -40C 850 temps. Will be interesting to see how cold Key Lake SK is Saturday morning. They routinely hit -40C with no problem in Arctic ridges. They could be close to -50C under that cold core.

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  24. Rob, do you know when the least snowy decembers were?

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  25. Environment Canada predicts -45°C in Lynn Lake tomorrow night, with a wind chill of .. -60! Crazy stuff!

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  26. Re: Least snowy Decembers. I'd have to look that up.. but Dec 1877 must be at the top. Only 0.5 cm recorded the whole month during our warmest December ever. 23 mm of rain between the 19th and 24th.. high of +8C on the 23rd. No snow that Christmas and bad sledding because of all the mud!

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  27. 137
    WWCN12 CWWG 111033
    SEVERE WEATHER BULLETIN
    ISSUED BY ENVIRONMENT CANADA
    AT 4:33 AM CST FRIDAY 11 DECEMBER 2009.
    ---------------------------------------------------------------------
    WATCHES/WARNINGS IN EFFECT FOR NORTHERN MANITOBA...

    WIND CHILL WARNING FOR:
    =NEW= LYNN LAKE - LEAF RAPIDS - PUKATAWAGAN
    =NEW= BROCHET.

    BRISK NORTHWEST WINDS AND TEMPERATURES NEAR MINUS 30 WILL GIVE
    EXTREME WIND CHILL VALUES OF MINUS 45 TO MINUS 50 THIS
    AFTERNOON.

    THIS IS A WARNING THAT EXTREME WIND CHILL CONDITIONS ARE
    IMMINENT OR OCCURRING IN THESE REGIONS. MONITOR
    WEATHER CONDITIONS..LISTEN FOR UPDATED STATEMENTS.

    BLIZZARD WARNING FOR:
    CHURCHILL
    YORK.

    BLIZZARD BEGINNING LATER THIS MORNING AND PERSISTING INTO THIS
    EVENING.

    ---------------------------------------------------------------------
    ==DISCUSSION==
    A LOW PRESSURE SYSTEM INTENSIFYING OVER HUDSON BAY IS EXPECTED TO
    BRING LIGHT SNOW AND STRONG WESTERLY WINDS TO THE CHURCHILL AND
    YORK AREAS LATER THIS MORNING. VISIBILITIES WILL BE REDUCED TO LESS
    THAN ONE KILOMETRE AT TIMES TODAY. BLIZZARD CONDITIONS ARE EXPECTED
    TO GRADUALLY IMPROVE OVERNIGHT.

    COLD TEMPERATURES ARE EXPECTED TO RETURN FOR THIS WEEKEND AS ANOTHER
    SHOT OF COLD ARCTIC AIR PUSHES INTO WESTERN MANITOBA THIS AFTERNOON.
    AS A RESULT EXTREME WIND CHILLS ARE EXPECTED THIS AFTERNOON IN
    EXTREME NORTHWESTERN MANITOBA WHERE BRISK NORTHWESTERLY WINDS WILL
    GIVE WIND CHILL VALUES OF BETWEEN MINUS 45 AND MINUS 50. THESE
    EXTREME WIND CHILL VALUES WILL LIKELY SPREAD INTO EASTERN AREAS OF
    NORTHERN MANITOBA TONIGHT AND SATURDAY AS THE COLD AIR PUSHES
    EASTWARD.

    PLEASE REFER TO THE LATEST PUBLIC FORECASTS FOR FURTHER DETAILS.

    END

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  28. Looks like we finally will get some snow tonight into this weekend!

    Not much, but enough to coat the ground!

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  29. How much? I'm hoping at least 3 CM.

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  30. I see around Winnipeg people have
    "SNOW REMOVAL" signs up!!!

    I bet their just itching to plow some snow!!!!

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  31. Seems as if there is a poll in there somewhere.. Green xmas/new yr?

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  32. Snow could be a balmy relief..from this weather. Overnight low 3weeks ago of + 9C..and some of us wished for frigid cold weather to start.

    What were we thinking?

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  33. As someone was saying earlier...

    -60 windchill in Lynn Lake tonight!!!

    That is mind numbing COLD!
    Frostbite can occur in less than 2 minutes!

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