Wednesday, January 14, 2009

Wicked Wednesday windchills!

Another Arctic ridge of high pressure is building into the Prairies, bringing a fresh outbreak of bitterly cold air over southern MB today. The problem today will be northwest winds of 20-30 km/h combining with -30 to -35 temperatures this morning to produce dangerous windchills of -45 to -50. At these values, exposed skin will freeze within 5 minutes. Note that many school buses and rural schools are cancelled when the windchill is -45 or lower, so that will be the case for many school kids across southern MB this morning. Windchill values will moderate to minus 40 or so this afternoon as temperatures rise to the minus 25 to minus 30 range. Another cold night is on tap tonight with lows back in the mid minus 30s (and windchills in the minus 40s), and then the long anticipated warming trend will begin this weekend, with temperatures projected to go above freezing by Sunday. So hang in there.. relief is on the way!

14 comments:

  1. Note that I'm getting sporadic wind readings from my weather station.. it's frequently showing calm when the wind is actually blowing. Must be getting tired of the cold. Whatever the case, do not use windchill readings from my site.. they are not representative of actual conditions.

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  2. CYWG 14/01/09
    Time Temp W/C
    7:00 -34 -49
    6:00 -34 -47
    5:00 -35 -48
    4:00 -35 -49
    3:00 -34 -49
    2:00 -33 -45
    1:00 -35 -48
    0:00 -37 -51 BRUTAL! hope your cat is indoors!

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  3. The low was only -38C in Steinbach yesterday.

    This morning the temperature is -36C with a wind chill of -46.

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  4. Tonight could be just as cold if not colder than Tuesday morning!

    Thursday morning lows could hit
    -40 C in many areas!

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  5. Daniel.. Unlike Tuesday morning, the core of the Arctic high passes to our south and west into the Dakotas tonight. That leaves much of the Red River valley and SE MB with a bit of wind tonight that will likely keep temperatures from dropping as much as they did Tuesday morning when the ridge was right over us. SW Manitoba has a better chance of seeing lows in the -35 to -40C range tonight closer to the ridge. For the rest of us, we're probably looking at lows in the -30 to -35C range.

    Regardless, it's cold. Hard to believe we'll be going above zero by Sunday.

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  6. The amount of warm air that models show surging across the Prairies this weekend is incredible given how cold it is right now. Models show an area of +16-18C air at 850 mb moving over Alberta on Sunday, which could easily mix down in areas with no snow cover out there to the lee of the Rockies. The warmup in southern MB on Sunday will be dramatic as we get a westerly flow that will finally flush out any remaining Arctic air Saturday night, and tap mild Pacific air to our west. Current forecast high of +2C Sunday in Winnipeg is certainly attainable given our westerly flow, with +4 to +7C temperatures possible in downslope areas to the east of Riding Mtns (like Dauphin) Looks like we should stay with those melting temperatures through Monday and Tuesday before we cool off again by mid week.

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  7. I expect tomorrow to be similar to today's weather conditions. Lows -30 to -37, and winds of 5 to 15km/h in the morning.

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  8. For tonite.. areas under the arctic ridge from Regina and Estevan down thru Minot will be in for brutal temperatures. Watch for -40 C by midnight in those areas before return flow kicks in closer to dawn. Minot air force base in particular will be interesting to watch with their 100 cm snow pack. (Minot airport always stays warmer... either better mixing from escarpment or flow off the city).

    True to form.. temperatures at YWG behaved erratically last nite. Before the stronger gradient kicked in after midnite... -37 C was attained with cold air drainage. The surrounding open country CWB stations reported lows of -34 to -36 C... only Sanford also checked in at -37 C.

    Incredible surge of warmth as Rob mentioned by Sunday... +10 C temps at 850 MB over western RRV. However the NNW upper flow makes me nervous. From past experience.. warm fronts can literally stall out just west of the RRV. It's also possible for any shortwave dropping down the flow to push a backdoor cold front thru our area. A shallow layer of cold air could easily slide under the warm air aloft.

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  9. I think the RRV will probably be -34 to -36 again tonight. It certainly won't be as cold as Tuesday night, but cold nonetheless.

    925mb winds are forecast to be stronger than this morning, which means wind chill values should remain between -40 and -50 until noon tomorrow. It could also prevent the low from going to the more extreme temperatures. However the 925 flow is non-existent over south-west MB, so as Daniel said, it could be -40+ there.

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  10. Good call Daniel.. Estevan down to -40C, and it's only 8 pm! (that's after getting to a high of only -31C this afternoon!)

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  11. -40 in Estevan with a 15km/h wind! Now that is COLD!

    Cold spot in SK is Key Lake (big surprise) at -41C. Cold spot in MB is Roblin, at -35C.

    It will probably be -30 to -35 tonight over most of southern Manitoba, with the exception of western MB. Wind chill values will likely be -40 to -50.

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  12. I know everyone is watching tonights cold tempertures but does anyone know what is going to happen on Friday in regards to snowfall? I see weathernet is saying 5cm but they`ve been saying that for the last 5 days. Env Can has been saying flurries but today changed it to periods of snow with no amounts and accu weather has been saying flurries with a dusting. Anyone have any ideas as to what to expect or will this be another system that just misses us or is it just a weak system running through?

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  13. Looks like a warm front will be pushing through the area today!
    With a slow moving front a periods light snow might accumulate to a couple cm of snow!

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  14. Record low of -44F in Bismarck ND this morning.. just 1F off their all time low of -45F set in 1936 and 1916.

    On the Bismarck NWS website, they show a photo of a staff member throwing a cup of coffee into the record cold air.. nice touch!

    http://www.crh.noaa.gov/bis/

    Estevan also hit a record low.. an astounding -43.4C, their coldest since Feb 16 1936 when they hit their all time low of -46.7C That 1936 cold snap was brutal.. 2 months of -30 to -45C temperatures across the Prairies in Jan and Feb. That summer, we endured one of the worst heat waves on record with temperatures of 40-45C in July. What a year that was for extreme temperatures.

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