Cooler, Cloudy Wednesday Followed By Sunnier, Warmer End of Week

A weak disturbance will bring slightly cooler and cloudier weather to Winnipeg on Wednesday, but mild temperatures quickly return.

Two features will combine to bring a change in the weather to Winnipeg today. The first is a large area of high pressure tracking across the Prairies that will sprawl across Manitoba today. It will bring dry northerly winds of 20–30 km/h to the region today and cooler highs in the upper teens. The second is a weak mid-level disturbance that will move through the area. It will spread cloud cover into the Red River Valley through the morning and bring a chance of showers for the afternoon hours.

Skies will clear out in the evening with easing winds. A ridge from the high pressure system over the province will move into the Red River Valley overnight, sending lows to a seasonably chilly +3 °C.

RDPS 10m Wind and MSLP Forecast valid at 18Z Wednesday September 23, 2020
A sprawling high pressure system will bring slightly cooler temperatures to southern Manitoba today and tonight.

The warm weather quickly returns to the region on Thursday as another low begins pushing eastwards across the Prairies. Winds will pick up out of the south into the 20–30 km/h range in the afternoon as temperatures climb to a high near 23 °C. A warm front will approach through the day, bringing partly cloudy skies to the region.

Skies will stay cloudy overnight with a chance of showers as a trough and cold front successively move through the area. The combination of cloud cover and persistent south wind will keep temperatures mild with a low near 14 °C.

Friday will be another warm day in Winnipeg. The city will see a high near 24 °C with a westerly wind near 20 km/h and partly cloudy skies. Not much else to say about the day; it’ll be a nice one! Temperatures will dip to a low near 10 °C under partly cloudy skies on Friday night.

Long Range Outlook

Winnipeg will see a mild weekend with highs near 20 °C and lows around 9 °C. Both Saturday and Sunday should bring partly cloudy skies with a slight chance of rain showers on Saturday. On Sunday night, a low will begin moving through the region, bringing rain through the region and ushering in strong northerly winds and a return to seasonal temperatures.

Today’s seasonal daytime high in Winnipeg is 16 °C while the seasonal overnight low is 5 °C.

Warming Up For The Weekend

Temperatures will warm up for the weekend, kicking off an extended period of seasonably mild temperatures.

Near-seasonal temperatures will return to Winnipeg today as a warm front pushes eastwards across the province. This front will also bring cloud cover with it, replacing morning sun with cloudy periods by midday. The city will see a high near 16 °C this afternoon with southerly winds of 20–30 km/h. Skies will clear by the evening as the front pushes off to the east. The winds will keep up near 20 km/h tonight and it will be a much warmer night with a low near 8 °C.

On Saturday, the region will see mainly sunny skies and light southerly winds. Temperatures will climb to a seasonably mild high of 23 °C. There may be a bit of high-level forest fire smoke, but most dispersion models show the denser plume of smoke lifting into the central and northern Prairies. Winnipeg will see a low near 13 °C on Saturday night as winds pick up out of the southeast to 30 km/h. Some cloud cover will begin to push into the region overnight as a low approaches from the west.

RDPS 2m Temperature Forecast valid 21Z Saturday September 19, 2020
The cold snap will break this weekend as temperatures climb into the 20s across Southern Manitoba on Saturday.

Winnipeg will see mixed to mostly cloudy skies on Sunday as a low pressure system pushes into the province. Moderate southerly winds of 30–40 km/h will persist through the day as temperatures climb to a high near 24 °C. A few showers will move into the region, but most will weaken moving into the Red River Valley. The cloud cover will break up in the evening as a trough moves through, then temperatures will dip to a summer-like 16 °C with a chance of showers early Monday morning.

Long Range Outlook

Next week will continue to bring seasonably mild temperatures to Winnipeg with highs largely staying in the 20–25 °C range. A few chances of showers will occur through the week, but it looks like great end-of-September weather.

The one unknown heading into next week will be how much of the West Coast wildfire smoke moves into the region. Details on that should become more clear as the weekend progresses.

Today’s seasonal daytime high in Winnipeg is 17 °C while the seasonal overnight low is 6 °C.

Chilly Fall Weather Leads to Warm (?) Weekend

Winnipeg will see rather cool conditions mid-week gradually give way to a what may be a pleasant weekend.

Chilly fall weather arrives again in Winnipeg today behind a cold front sweeping through this morning. Northwest winds up to 30 gusting 50 km/h will usher in a cool Arctic air mass through the day. Temperatures will struggle to recover much, reaching a high this afternoon near 11 °C. The city should see a fair amount of sun today, aside from a bit of morning cloud. A few clouds will likely linger into the afternoon through some shallow convection or streaming off the lakes.

A sprawling area of high pressure will move into the province tonight and bring lows down close to the freezing mark. Skies will vary from partly cloudy to mixed and the winds will quickly ease in the evening.

10m Wind and MSLP Forecast valid 00Z Friday September 18, 2020
A sprawling high pressure system, pictured here as forecast for late Thursday afternoon, will shape Winnipeg’s weather over the coming days.

On Thursday, this slow-moving system will linger over the province and bring light winds. Winnipeg will see some morning cloud give way to afternoon sun as temperatures begin to recover with a high near 14 °C. Temperatures will dip to a low near +2 °C on Thursday night.

The high will finally begin pushing off to the east on Friday. Temperatures will continue to rebound with highs near 16 °C. A southerly wind will strengthen to 20–30 km/h in the afternoon with partly cloudy skies. With the high well to the east by Friday night, temperatures will return to a near-seasonal low around 8 °C.

Long Range Outlook

A warmer air mass will push into Manitoba this weekend with highs potentially climbing into the 20s. We say potentially, though, because there’s also a good chance that it will bring another batch of forest fire smoke from the western United States. If that smoke were to push into the region, it would likely limit temperatures to the mid-teens rather than seasonably warm low twenties. Cloudier conditions are likely on Sunday with a chance of showers late in the day and into the night.

Warmer conditions are possible well into next week, with the conditional that forest fire smoke could blanket the sky and hinder temperatures at times.

Today’s seasonal daytime high in Winnipeg is 18 °C while the seasonal overnight low is 6 °C.

Cooler, Pleasant Weekend Ahead

Winnipeg will see seasonably cool weather right through the weekend with otherwise pleasant conditions.

A ridge of high pressure will bring sunny skies to the Red River Valley as it pushes into the province today. Winds will be breezy out of the northwest again at 30 gusting 50 km/h, keeping temperatures cool. Winnipeg should see a high near 20 °C. Skies will stay mostly clear tonight as the winds ease off and temperatures dip to a low near 7 °C.

Saturday will bring a return to seasonal temperatures for Winnipeg with a high near 22 °C. Winds will stay light as they shift to the southeast for the afternoon. Skies will start off sunny, but more cloud will build into the region through the afternoon. The cloudier conditions on Thursday night will help keep temperatures slightly warmer with a low in Winnipeg near 13 °C.

RDPS 2m Temperature Forecast valid 21Z Saturday September 5, 2020
On Saturday, an approaching low pressure system will bring summer heat to southern Saskatchewan and southwestern Manitoba with highs of 25–30°C. Unfortunately, the Red River Valley won’t see any of that; it will drop southwards into the Dakotas as it approaches.

A disturbance passing through the region on Sunday will bring mainly cloudy skies to the city. Temperatures will reach a high near 20 °C, but a cold front sweeping through in the afternoon will usher in significant change. Winds will shift northwesterly at 20–30 km/h in the afternoon behind the front and usher in a much cooler air mass. Skies will stay mostly cloudy right through Sunday night as temperatures dip to a low near 8 °C.

While this system will spread rain across Manitoba on Sunday, it should stay well north of the city. Areas from west-central Manitoba southeastwards into the Pinawa region will likely see around 10 mm of rain through Sunday.

Long Range Outlook

Daytime highs will plummet well below seasonal values to start the week as highs struggle to climb over 10 °C. On Monday and Tuesday, a persistent north wind combined will produce lake-effect showers in the lee of both Lake Manitoba and Winnipeg. Winds will shift westerly on Wednesday, bringing an end to the lake-effect precipitation and gradually pushing temperatures back towards seasonal values.

Also on Monday, an upper-level disturbance will drop into the region. It will spread a broad area of showers that will likely move through the Red River Valley as well.

Today’s seasonal daytime high in Winnipeg is 21 °C while the seasonal overnight low is 8 °C.