The Red River Valley will be grazed by a little more snow today, then a bitterly cold air mass will entrench itself over the region.
If the dump of snow yesterday wasn’t quite enough for you, a little more snow is possible this morning. One last disturbance will move through the region this morning, bringing 4–8 cm of snow to southeastern Manitoba. This area of snow will also graze the Red River Valley with 2–5 cm possible along a southwest to northwest line draped across the area.
The snow will clear out this evening, leaving behind clear skies as bitterly cold temperatures push into the region.
The big weather story for the rest of the week will be the cold temperatures that will stay locked over the region. Daytime highs will be around 15 °C below seasonal in the -30 to -25 °C range right to Saturday. Overnight lows will vary, but there is the potential for some very cold nights with lows dipping below -35 °C. Extreme cold warnings are a certainty for the region in the days ahead as wind chill values of -40 or lower are likely unavoidable.
A few flurries may be possible later this week, but the organized snowfall will be over for a bit after today.
Long Range Outlook
Forecasts have temperatures moderating beginning on Sunday and lasting through much of next week. This warmer weather will come with some snow as well with chances both next Monday and mid-week.
Today’s seasonal daytime high in Winnipeg is -12 °C while the seasonal overnight low is -22 °C.
Another shot of bitterly cold air is poised to crash through Manitoba this weekend with daytime highs plummeting back into the -20’s and overnight lows dipping close to -30°C.
The cold snap this weekend is looking slightly different from earlier in the week and now comes with some good news, some bad news, and a bit more uncertainty. The overall pattern has shifted further west, with the core of the coldest air now forecast to slump southwards over the Saskatchewan/Manitoba border instead of the Red River Valley. This will shift the coldest temperatures westwards, which results in the good news for Winnipeg: it likely won’t be quite as cold as it looked earlier in the week, but just by a couple degrees. The bad news, however, is that there will be a bit more wind throughout the Red River Valley as the light winds in the centre of the ridge shift west with the coldest air.
The cold air begins working in today; temperatures will climb to around -19°C today for the daytime high, and then top out between -23 and -21°C on Saturday and Sunday. Overnight lows over the coming days will likely be around -28 or -29°C for the coming 3 nights, depending on "the uncertainty."
The complicating factor with the ridge of high pressure pushing further west will be cloud cover. Two aspects complicate the fair sky forecast:
Uncertainty in how much cloud cover will remain on the east side of the ridge. Many of the Arctic ridges this winter have been "dirty ridges," that is, they are "polluted" by significant amounts of low-level cloud. There are some indications that this may be the case with this next system, but to a much lesser extent compared to others this winter based on satellite imagery of upstream conditions.
Complications with an inverted trough rotating through Central Manitoba. While much of the province will be under the influence of the Arctic ridge, several forecasts show a weak inverted trough associated with a system rotating through Ontario digging into the ridge through Central Manitoba. This feature could produce more cloud that would gradually slump southwards into the Red River Valley.
The biggest uncertainty with cloud cover is Saturday. My best guess at this point is that we’ll see a bit of cloud, however it will overall be a mixed-sky to sunny day. There is an off-chance, though, that we end up mainly cloudy. Cloud cover can marginally impact the daytime high (likely increasing it by around 2°C), and substantially impact overnight lows (keeping them significantly warmer than in clear skies).
That said, with winds likely between 10-20 km/h at night, wind chill values in the -35 to -40 range will be widespread over Southern Manitoba over the coming nights, with -40 or colder wind chills quite likely over southwestern Manitoba. Here in the Red River Valley, -40 wind chills seem unlikely, but could be seen if temperatures get a couple degrees colder than forecast at night or the winds are a tad stronger. Environment Canada issues extreme cold warnings when the wind chill *or* temperature is expected to drop below -40.
Sunday has more confidence in seeing mainly sunny skies.
Long-Range Outlook: Hints of Warming
The first half of the coming week still looks quite cold with daytime highs near -20°C and overnight lows in the -25 to -30°C range. By mid-week, however, it looks like a big change will be on the doorstep.
Current long-range forecast models are beginning to show with higher confidence that the polar vortex will finally be displaced allowing a milder zonal flow to develop. While it doesn’t look like a huge surge of warm air, seasonal to slightly above seasonal temperatures by the end of the week look fairly reasonable.
Right now, the average daytime high is -13°C and the average overnight low is -24°C.
An Alberta Clipper moving through the province on Friday into Saturday will pack a potent punch – likely the worst storm so far this winter for most places, including Winnipeg – bringing a decent shot of snow alongside strong winds producing significant blowing snow. To cap things off, a bitterly cold air mass will move into the region bringing extremely cold temperatures & wind chill.
-14°C / -21°C
Early morning flurries, then snow beginning late in the day
⇓ -26°C / -32°C
Snow tapering off then clearing; windy & cold
-27°C / -33°C
Friday will start off mainly cloudy as a brief shot of light snow exits the province. Amounts from this band will be just a couple cm or less and this leading impulse will be nothing compared to what will be moving in later in the day.
Before that, though, skies will become more mixed with temperatures gradually climbing to around –14°C. Winds will remain relatively light until the Alberta Clipper moves into the region tonight.
Snow will push into Southwestern & Parkland Manitoba this afternoon and quickly spread eastwards across the remainder of the province by the evening. Snowfall will be quite intense, with rates reaching as much as 2cm/hr in the heaviest band. The heaviest snow will fall through Friday night and then taper off from west to east through the day on Saturday.
By the time the snow tapers off on Saturday, up to 25cm of snow may have fallen through the heaviest band of snow which is centered along the international border and cuts across the Southern Red River Valley. Winnipeg will likely receive on the higher end of 10–15cm of snow while amounts then taper off through the northern Parkland region and central Interlake.
Measuring that snow may be quite difficult, though, as strong northwesterly winds to 40km/h move into the Red River Valley. With all the fresh snow, widespread blowing snow is very likely on area highways with the potential for significant restrictions to visibility. In areas of the southern Red River Valley, we may even see the development of a full-on blizzard with the higher amount of fresh snowfall and slightly stronger winds due to the funnelling of the valley. Driving conditions will likely be quite poor, so be sure to give yourself plenty of additional time if you need to travel and remember to always carry a winter survival kit in your vehicle.
There’s only one story once the snow tapers off on Saturday and skies begin to clear: bitter cold. It’s going to get very, very cold across the entire province with the coldest air mass of the season diving southwards behind the clipper. Saturday will see temperatures slipping through the day to around –26°C which will then plummet down to –32 or –33°C overnight. With winds of 10–20km/h persisting overnight, wind chill values of –40 to –45 will be widespread through Southern Manitoba.
Sunday will bring barely any recovery with temperatures struggling to get to a paltry –27°C. Expect the low on Sunday night to dip back down to –32 or –33°C with wind chills agin in the –40 to –45 range.
No Warmth In The Long-Range
Looking ahead to next week, conditions look dry with little to offer as reprieve from the cold. Daytime highs will moderate towards the –20°C mark, but overnight lows in the low minus-twenties will be sticking around for a while.
Looking even further ahead, there are little in the way of strong signals. There’s about a 50/50 chance of below-seasonal temperatures continuing, but compared to this week, it’s at least a trend towards more seasonal temperatures. It’s not much, but when we’re getting as cold as we will this weekend, I’ll take what I can get.
This will likely result in an extreme cold warning being issued by Environment Canada, as their criteria is a temperature or wind chill colder than –40. ↩
This week will feature the coldest weather we’ve seen since last winter, just what you were hoping for I’m sure!
-12°C / -16°C
Skies will clear on Monday morning, giving way to a sunny, but cold day. High temperatures will be in the minus teens with a brisk north-west wind. Watch out for slippery sections on the roads, as freezing drizzle and snow from yesterday will certainly still be an issue on untreated surfaces.
-9°C / -17°C
Mainly cloudy with chance of flurries
Tuesday will be one of the warmer days this week (if you can believe it). Temperatures will hover around the -10C mark with a chance of flurries throughout the day. The mainly cloudy skies will be partly responsible for the warmer conditions, trapping heat near the surface. Winds will be fairly light and from the north-west.
-18°C / -30°C
Wednesday looks to be the coldest day since last winter as a strong surface high descends into southern Manitoba. High temperatures will barely crack the minus teens and lows on Wednesday night could approach -30C. A brisk northerly wind will add a decent wind chill factor as well, making it feel even colder, if that’s possible!
The long range forecast looks awful, so there’s barely any point even talking about it. Temperatures look to remain below seasonal for the foreseeable future…hopefully you’re ready for winter, because it’s here!
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