Two Days Of Seasonal Weather, Then A Prolonged Cold Snap

Brad Leave a comment

Winnipeg will see breezy conditions with seasonably mild temperatures today, but a cold front passing through on Saturday will usher in an extended period of markedly cooler weather.

A low pressure system crossing the Prairies will finally bring seasonal temperatures back to southern Manitoba today. With a brisk southerly wind increasing to 30 gusting 50 km/h, temperatures will climb to a high near 11°C. Morning sunshine will give way to mixed skies, but things should stay dry with no precipitation in the forecast. The low will continue to advance towards the province tonight, keeping skies mixed and maintaining the southerly winds. Winnipeg should see a low near 7°C.

The city will still see seasonal temperatures on Saturday, but the day will be much less pleasant as a cold front sweeps through early in the morning. Temperatures will hover near the overnight low of 7°C then begin cooling later in the day. Winds will be breezy out of the west-northwest near 30 gusting 50 km/h and skies will be mostly cloudy. Again, no precipitation is forecast. Skies will stay cloudy on Saturday night with a northwest wind near 20 km/h and a low of -1°C.

RDPS 2m Temperature Forecast valid 21Z Friday October 25, 2019
An approaching low will bring seasonably mild temperatures to Winnipeg today, but a prolonged stretch of cooler conditions will quickly move in behind it.

Sunday will bring cloudy conditions to the city with temperatures remaining steady near 0°C. This will mark the beginning of a prolonged cold snap that will entrench the city in below-normal temperatures for the next week. The northwest winds will gradually ease through the day and into the evening. Some flurries will be possible in the city as the cold air and northwest wind will bring a chance of lake-effect snow off of Lake Manitoba. Temperatures will head to a low near -4°C on Sunday night with mostly cloudy skies.

Long Range Outlook

Unfortunately, a long stretch of cold weather is on the way for Winnipeg. Arctic air will plunge southwards through much of North America through the week as a significant upper-level trough develops.

GDPS 850mb Temperature Anomaly Forecast valid 00Z Tuesday October 29, 2019
Temperatures will stay well below-seasonal next week for much of the western portions of Canada and the United States.

The result will be a week of variable cloudiness, temperatures struggling to reach 0°C, and several chances of accumulating snow.

Today’s seasonal daytime high in Winnipeg is 7°C while the seasonal overnight low is -3°C.

RDPS 2m Temperature Forecast valid 21Z Thursday October 24, 2019

Cool With An End-of-Week Warm Up

Brad Leave a comment

Winnipeg’s cool weather will stay for a couple more days, then warmer weather arrives for the end of the week.

A couple cool days are coming up for Winnipeg as an Arctic air mass remains entrenched over the region. The city will see a high of only 3°C today as northwest winds of 30 gusting 50 km/h continue. Skies will stay cloudy for much of the day as a combination of system1 and lake-effect cloud moves through.

As the day progresses and cooler air aloft pushes into the area, both Lake Winnipeg and Manitoba will likely begin to produce some lake-effect snow. Winnipeg may see some of this snow or rain in the morning. By the afternoon, the precipitation will mainly fall in the lee of the lakes. With a northwest wind, this will likely mean that Winnipeg will end up between a band of snow or rain showers to the west and to the east.

Lake-effect flurries are possible in the lee of the lakes today. The most likely areas to see precipitation will be in the lee of Lake Winnipeg.
Lake-effect flurries are possible in the lee of the lakes today. The most likely areas to see precipitation will be in the lee of Lake Winnipeg.

The lake-effect precipitation will taper off overnight as the winds ease and turn westerly. The city will see a low near -2°C as the cloud cover begins breaking up.

Thursday will be a cool day with a high of just +4°C. A ridge of high pressure moving through will keep the winds light, but skies will remain partly cloudy to mixed. A warm front pushing eastwards across the Prairies will spread a southerly wind into the Red River Valley on Thursday night along with a bit of cloud. Winnipeg’s low will sit somewhere around the freezing mark.

A return to seasonal warmth arrives on Friday as temperatures climb to a high near 10°C. The region will likely see a fair amount of cloud as the warmer air pushes as well as a strengthening southerly wind into the 30 to 40 km/h range. These breezy winds will persist through the night, keeping the low relatively mild at around 6°C.

Long Range Outlook

Seasonal warmth will stick around for Saturday, but a passing low will send a cold front sweeping through the region on Saturday night. While the Red River Valley won’t see much precipitation, it will plunge the region into an extended stretch of below-seasonal temperatures. There isn’t much rain or snow in the extended forecast, but with the cooler temperatures it’s likely that lake-effect flurries will be relatively common in the coming week.

Today’s seasonal daytime high in Winnipeg is 7°C while the seasonal overnight low is -3°C.

  1. “System” cloud is the cloud associated with a low pressure system. ↩

Week’s Rainy Start Leads to Much Cooler Weather

Brad Leave a comment

More rain will move through the region today, followed by northwest winds and much cooler conditions.

Rain will move through the region today as a Colorado Low moves into NW Ontario. The rain will spread from southwest to northeast across the Red River Valley and have a sharp edge on the northwestern side. This will result in rainfall accumulations dropping from around 5 mm to nothing over a short distance. Winnipeg should see around 5 mm of rain, although the city could see a bit more if the band ends up shifting a bit west or east.

Generally speaking, the eastern Red River Valley into the southeast corner of the province will see 5 to 10 mm of rain. Narrow convective banding could result in localized accumulations of 10 to 20 mm. The western Red River Valley will see amounts generally around 5 to 10 mm in the southwest diminishing to nothing near Portage la Prairie.

While the NAM rainfall accumulations in the Red River Valley for today might end up a tad on the high side, the areas that will see rain look well-represented.
While the NAM rainfall accumulations in the Red River Valley for today might end up a tad on the high side, the areas that will see rain look well-represented.

Aside from the rain, highs today will be a seasonably cool 7°C in Winnipeg. A brisk northwest wind will develop through the day, picking up to 30 gusting 50 km/h this afternoon. The wind will then increase to 40 gusting 60 km/h this evening. While the rain will taper off later today, the chance for showers (or eventually flurries) will persist overnight. Temperatures will dip to a low near +2°C.

Cloudy skies will continue in Winnipeg on Tuesday with a continued chance for some scattered showers or flurries. The moderate northwest winds will continue and temperatures will cool with a high of only 5°C. Skies will stay cloudy on Tuesday night with winds beginning to ease as temperatures head to a low near 0°C.

The sun might be able to poke out on Wednesday, but Winnipeg will likely continue to see mainly cloudy skies. The cold air will continue to push into the region, keeping highs cool at just +3°C. Winds, while lighter than Tuesday, should still persist out of the northwest at 20 to 30 km/h. The cloud cover will begin to break up a bit on Wednesday night as the winds finally ease. Winnipeg will see a low near -3°C on Wednesday night.

Long Range Outlook

The rest of the week should bring mixed skies to the city and dry conditions. The cool weather will persist on Thursday, but seasonal temperatures may return (alongside some cloud) for the end of the work week into the weekend.

Today’s seasonal daytime high in Winnipeg is 8°C while the seasonal overnight low is -2°C.

A Mild Weekend Before Cooler Weather Returns

Brad Leave a comment

Winnipeg will see seasonably mild temperatures this weekend before more rain and cooler weather returns.

Winnipeg will get to enjoy a comparatively pleasant weekend when compared to the last! The city will see daytime highs in the low teens right through the weekend and overnight lows hovering a bit above 0°C. This morning’s southeast winds near 30 km/h will ease later today, then stay light through the rest of the weekend.

A trough moving through today will keep skies overcast across the region today. While there may be a slight risk of some late-day rain for Winnipeg, it’s more likely that any precipitation develops to the east and northeast. Some sun will return for Saturday with mixed skies.

The Red River Valley will see a chance for more accumulating rainfall on Sunday night.

On Sunday, a low pressure system will move across the Dakotas into Minnesota, spreading more cloud back into the region. On Sunday night, winds pick up out of the north and some rain is likely over the Red River Valley. There’s uncertainty with amounts at this point, but 5 to 15 mm across the region seems likely.

Long Range Outlook

More rain is possible on Monday as colder air begins to push southeastwards across the Prairies. The rest of the week will likely bring mixed to cloudy skies with several lake-effect precipitation events developing off of the Manitoba Lakes through the week. Daytime highs will dip to the mid- to low single digits with overnight lows hovering around the freezing mark.

Today’s seasonal daytime high in Winnipeg is 9°C while the seasonal overnight low is -1°C.