Tag: Snow

Cool Weather Continues

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The rest of the week will bring more of the same: unseasonably cold temperatures.

Cold weather will continue for Winnipeg throughout the second half of the week as a persistent northwesterly continues to tap into Arctic air. Daytime highs will remain well below the seasonal value near 6°C over the coming days starting with a high near -2°C today that will slump towards -5°C by Friday. Overnight lows will keep with the trend as well, generally hovering near -15°C, about 10°C below seasonal.

Skies will be cloudier through the second half of the week than they were in the first. A sunny start to today will lead to mixed skies this afternoon as low-level instability develops. These clouds will dissipate as soon as the temperatures begins dropping in the evening. Quickly replacing them will be a more organized area of cloud associated with a weak low pressure system tracking across northern Montana into North Dakota. This will spread mostly cloudy skies into Winnipeg and the Red River Valley for Thursday. An area of organized light snow will likely spread eastwards through areas primarily south of the Trans-Canada Highway on Thursday morning, but flurries are possible for much of the day as another cold front slump southwards through the province. Skies will be back to mixed to mainly cloudy on Friday with a very slight chance of a flurry.

GDPS 300mb Height and Wind valid 12Z Thursday April 5, 2018
An entrenched and slow-moving vortex over southern Hudson Bay is sustaining a cold northwesterly flow over the Canadian Prairies

The wind won’t be too much of an issue today, but on Thursday they’ll pick up out of the northwest again up to 30 km/h. The winds will ease on Thursday night, then pick back up to 30 gusting 50 km/h on Friday. Brrr!

Long Range Outlook

The extended forecast hasn’t changed too much from our last forecast: a slow and gradual trend towards seasonal conditions. That said, what is considered seasonal is changing quickly now; the seasonal daytime high is increasing by 0.4°C per day right now, so today’s 6°C will be nearly 9°C by this time next week. That said, it is beginning to look like temperatures may return to seasonal values by the latter half of next week, so relatively speaking, a big warm-up might be in store next week!

Winnipeg’s seasonal daytime high is currently 6°C while the seasonal overnight low is -5°C.

Variable Cloudiness, Cool Temperatures, And A Chance of Flurries

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Winnipeg will see variable cloudiness over the next few days with a couple chances for flurries. Below seasonal temperatures will continue as well, with little improvement expected until next week.

Winnipeg’s chilly morning will lead to a cool day with a daytime high of just -10°C, a whopping 15°C below seasonal for this time of year. The city will see a sunny start to the day, but cloud cover will build in from the west this afternoon associated with a low pressure system moving into Montana and North Dakota. As the cloud moves in, the city will see a slight chance of flurries, but the better chance for snow will be in the southwestern Red River Valley westwards to the Saskatchewan border. Skies will clear tonight with temperatures dipping back down to around -19°C again.

Saturday will bring more cool weather to the region with daytime highs once again near -10°C with gusty northwesterly winds of 30 to 40 km/h developing in the afternoon. Mainly sunny skies in the morning will give way to mixed to cloudy skies in the afternoon as cloud cover drifts southwards out of northern Manitoba. This cloud will bring a good chance of flurries with it. The cloud and chance for flurries will persist into the evening. Temperatures will drop to a low near -13°C on Saturday night with skies becoming mixed towards morning.

RDPS 12hr. QPF valid 00Z Sunday April 1, 2018
Much of Manitoba will see light snow or flurries on Saturday

Sunday looks to bring warmer temperatures to the region. The high temperature for Winnipeg should end up near -4°C: still below seasonal, but better than the days before it. Winds will be westerly at 20 to 30 km/h with mixed skies. Those mixed skies look like they’ll stick around Sunday night as temperatures dip to a low near -13°C.

Long Range Outlook

Next week looks like it will bring benign weather to Winnipeg with temperatures gradually climbing back towards seasonal by next weekend. No significant precipitation is expected through the week, although a few flurries may roll through a few times.

Winnipeg’s seasonal daytime high is currently 5°C while the seasonal overnight low is -6°C.

Arctic Blast Pushes into Southern Manitoba

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Temperatures will drop significantly below seasonal values over the coming days as Arctic air surges southwards behind the Alberta clipper that brought mild temperatures to the region on Tuesday.

An Alberta clipper exiting the province this morning will usher in significantly cooler temperatures. Northwesterly winds will increase to 40 gusting 60 km/h this morning, cooling temperatures to around -5°C in the Red River Valley by late this afternoon. This cooling trend combined with the wind will make for a positively miserable feeling day. The morning cloud will break up, leaving mixed skies in Winnipeg and the Red River Valley, but the cold air diving southwards will produce instability in the lower atmosphere, bringing a chance of flurries that will persist until evening.

3km NAM Forecast Sounding for CYWG valid 21Z Wednesday March 28, 2018
This 3km NAM forecast sounding for Winnipeg shows the instability expected to develop in the low levels as colder air surges southwards.

Winds will taper off this evening and Winnipeg will head towards an overnight low near -10°C under partly cloudy skies.

On Thursday, a mid-level disturbance moving from central Alberta southeastwards into North Dakota will bring increasing cloudiness to Winnipeg. Temperatures will reach a high near -5°C by midday, but then the Arctic front will drop southwards through the Red River Valley and send temperatures plummeting. Northerly winds of 20 to 30 km/h will persist behind the Arctic front into the evening. Much of southern Manitoba will see the potential for flurries along the Arctic front on Thursday afternoon.

Significantly colder temperatures will move into the region behind the Arctic front, sending overnight lows down towards -19°C.1

GPDS Forecast 2m Temperature valid 12Z Friday March 30, 2018
The GDPS has temperatures as low as -24°C in the Red River Valley on Friday morning, but may be producing temperatures that are too cold

Friday will be a downright chilly late-march day with partly cloudy skies as more clouds pop up for the afternoon. Light northwesterly winds of 10 to 20 km/h will continue with temperatures climbing to a high near -9°C. Temperatures should drop to a low near -18°C once again on Friday night.

Long Range Outlook

Temperatures will moderate slightly on the weekend, but the trend of below-seasonal temperatures is forecast to continue into the middle of next week. No significant precipitation events are forecast for the next 7 days.

Winnipeg’s seasonal daytime high is currently 4°C while the seasonal overnight low is -7°C.

  1. Sometimes models struggle with overnight lows under Arctic ridges. The GDPS is forecasting a low near -23°C, but tends to cool too much due to excessive radiational cooling. Most other models have solutions closer to -13 to -15°C, but that is likely too warm. We’ve picked 19°C as a relatively happy medium, a couple degrees colder than the Barthrom calculation would suggest to account for the advective cooling in the evening. ↩

Seasonal Conditions To Be Ousted Mid-Week By Arctic Cold Front

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Winnipeg will see a couple more days of near-seasonal temperatures before a cold front swings through on Wednesday. Behind the passage of the cold front, a cooler Arctic air mass will settle over the region, bringing March to a close with significantly cooler-than-seasonal temperatures.

Mostly cloudy skies will continue in Winnipeg today with light winds and a high near +2°C. Temperatures will down to a low near -3°C tonight under mostly cloudy skies as well. A low pressure system moving through northern Manitoba tonight will bring westerly winds into the Red River Valley for Tuesday, which will help clear out the cloud cover and bring some sunshine back to the region. Temperatures should reach a high near +4 or +5°C, but with fairly warm temperatures aloft in advance of the next low pressure system, isolated areas with less snow cover could see temperatures as warm as +7 or +8°C.

RDPS 2m Temperature valid 00Z Wednesday March 28, 2018
Temperatures will vary between 0°C and +8°C across southern Manitoba on Tuesday

As the next low pressure system pushes into southern Manitoba on Tuesday night, more cloud will build back into the region with southerly winds of 15 to 25 km/h. There may be a passing shower or flurry on Tuesday evening, then temperatures will head towards a low near -1°C. The centre of the low pressure system will move through the Red River Vally on Tuesday night, bringing with it what looks like a fair chance of drizzle or freezing drizzle, depending on exactly what the temperature is at the time.

Forecast sounding for CWYG valid 09Z Wednesday March 28, 2018
Drizzle will be a distinct possibility on Tuesday night with a risk of freezing drizzle as temperatures drop below freezing Wednesday early Wednesday morning

Wednesday will see any remaining drizzle dissipate in the morning as a cold front slumps southwards. Temperatures will drop in the wake of the front to near -3°C by the evening as northwesterly winds of 30 to 40 km/h usher in a colder air mass. The cloud cover should break up on Wednesday night as temperatures drop to a low near -12°C.

Long Range Outlook

The remainder of March into the start of April will bring well below-seasonal temperatures to the region.

NAEFS 8-14 Day Temperature Anomaly Forecast — Valid April 2 to 9, 2018
NAEFS 8-14 Day Temperature Anomaly Forecast — Valid April 2 to 9, 2018

The remainder of the week into the weekend is looking unseasonably cold with daytime highs in the mid-minus to low-minus single digits and overnight lows in the -15 to -20°C range. The cold will linger at least through the beginning of next week.

Winnipeg’s seasonal daytime high is currently 3°C while the seasonal overnight low is -8°C.