Cool, Showery Weekend Ahead

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An upper low crossing the Prairies this weekend will keep temperatures cool in southern Manitoba with some showers or thunderstorms likely in the days ahead.

RDPS 12-hour Precipitation Accumulation valid 00Z Saturday August 12, 2023
Rainfall will be scattered throughout southern Manitoba today as showers and thunderstorms develop over the region.

A weak low pressure system will move across southern Manitoba today, the lingering feature from the system that brought 5 to 10 mm of rain to Winnipeg yesterday evening. As this low trundles into the Red River Valley this afternoon, it will support the development of scattered showers and thunderstorms. Severe weather is unlikely; energy will be limited with only 500 to 1000 J/kg of MLCAPE and bulk shear is also low at only around 15 to 20 knots. A marginally severe thunderstorm with large hail can’t be ruled out, but much of the area will mainly see the chance of showers and shorter-lived pulse thunderstorms.

Much of the activity will taper off in the evening, but a few showers may linger into the night, supported by both a shortwave sliding across the region and a weak trough extending from southern Manitoba northwestwards into central Saskatchewan.

On Saturday, the region will continue to see mixed skies with a slight chance of showers. Much less activity is expected than on Friday; there will be few, if any, features to support and organize showers. A bit of lingering instability may be left behind, but for the most part, mixed skies with just a slight chance of an isolated shower or two is most likely.

On Sunday, another low pressure system is poised to dive southeastwards through the province, bringing a good chance of rain to many parts of southern Manitoba. Some uncertainty remains on the track, but in general areas south of a line that runs roughly from Dauphin to the Whiteshell are likely to see accumulating rain at some point from early Sunday morning through the end of the day.

Temperatures over the next three days will be steady in the 20 to 25 °C while winds will generally be on the lighter side. Winds both today and tomorrow will mainly be westerly, while the passing low will shift the winds more northerly on Sunday.

Long-Range Outlook

It’s looking like unsettled conditions will continue into next week. Monday should bring a reprieve from any wet weather, but the chance of rain will return several times through the rest of the week. Winnipeg’s daytime highs and lows will sit at near-seasonal values through next week.

Today’s seasonal daytime high in Winnipeg is 26 °C while the seasonal overnight low is 12 °C.

Pleasant Summer Weekend Ahead

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An area of high pressure building into Manitoba will bring pleasant summer conditions to southern Manitoba this weekend with a low chance of an isolated thunderstorm or two.

RDPS 500mb Height and Wind Speed Forecast valid 21Z Sunday July 30, 2023
An upper ridge will begin to develop over the Prairies by the end of the weekend, spreading warm weather through the region.

To end the work week in Winnipeg and area, northerly winds behind a cold front will bring seasonably cool temperatures to the area. With gradually clearing skies, temperatures will climb to a high around the 20 °C mark this afternoon. Those northerly winds will ease from around 20 km/h today to light this evening, followed by temperatures dipping to a low near 10 °C.

On Saturday, warmer weather will return to the region with highs back into the mid-20s. Some cloud will develop in the afternoon as a weak upper trough swings across the region; some showers will be possible on Saturday night as it moves through. Winds will be light on Saturday night as an area of high pressure moves in. Temperatures will dip down to the low teens overnight.

On Sunday, warm weather returns with highs climbing back into the upper 20s under sunny skies. A few locations may even see temperatures reach the low 30s. Humidity won’t be an issue, making for a great day to enjoy some time outside.

Long Range Outlook

Next week will kick off with another beautiful day on Monday; daytime highs will again sit in the upper 20s under partly cloudy skies. More humidity arrives Monday night, though, and with it will come variable cloudiness and the chance of showers or thunderstorms. Unsettled conditions are possible, particularly in the late overnight or early morning through mid-week, then more settled conditions should return for the end of the week as the humidity across the region eases.

Today’s seasonal daytime high in Winnipeg is 26 °C while the seasonal overnight low is 13 °C.

Warm Summer Weather Ahead, But Smokier Conditions This Weekend

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Winnipeg will see warm summer temperatures over the next few days with plenty of sunshine for the weekend, but wildfire smoke will make a reappearance.

RDPS 2m Temperature Forecast valid 21Z Saturday July 22, 2023
Warm temperatures will continue across southern Manitoba this weekend with highs in the upper 20s.

Back from vacation, and I’m glad to say our first forecast back is a nice one. Over the next few days, the upper-level pattern over the Prairies will stay relatively stagnant. An upper ridge over the western Prairies will slowly build and nudge eastwards while a few disturbances rotate through central and northern Manitoba.

In Winnipeg, this will mean that temperatures will be fairly consistent in the days ahead; highs should sit in the upper 20s while overnight lows dip to the mid- to upper teens.

There will be plenty of sunshine in the city in the days ahead too. Today will bring some cloudy periods; there’s a small chance of an isolated shower or thunderstorm this morning as a shortwave moves through the area, and then again late in the day as a weak upper trough approaches from the northwest. 

Heading into the weekend, conditions will settle with sunny to mixed skies. Winds will be generally light, but Saturday could bring northwesterlies into the 20 to 30 km/h range.

The big question for the coming days will be just how much smoke the city will see with this weather pattern. Satellite pictures last night showed a decent plume of smoke to the northwest, corroborated by reports of poor visibility in The Pas and Flin Flon through the day. That smoke will gradually shift towards southern Manitoba. It shouldn’t be too bad today, but we’ll likely see smokier conditions develop at some point on Saturday and persist into Sunday.

Long Range Outlook

To start off next week, the upper ridge will build eastwards into Manitoba and bring more heat to the region. Temperatures will climb into the low 30s with dew points heading towards the 20 °C mark. This will make for a rather hot and humid first half of the week with Humidex values reaching into the upper 30s. Some unsettled weather is possible mid-week with near-seasonal temperatures returning to end the week.

Today’s seasonal daytime high in Winnipeg is 26 °C while the seasonal overnight low is 13 °C.

Heat Builds in for the Weekend

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An upper ridge building into the eastern Prairies will bring hot conditions to southern Manitoba this weekend.

RDPS 2m Temperature Forecast valid 21Z Sunday July 2, 2023RDPS 2m Dew Point Temperature Forecast valid 21Z Sunday July 2, 2023
Sunday will bring the warmest weather of the next few days as hot temperatures and high humidity build into the region.

Seasonably warm conditions will build into southern Manitoba over the next few days with daytime highs climbing towards the 30 °C mark. In Winnipeg, today will bring mainly sunny skies that give way to some cloud in the afternoon while a ridge of high pressure brings sunny skies for Saturday.

Temperatures both days will climb into the upper 20s. Humidity levels will be comfortable in the mid- teens both days. For those heading out to enjoy Canada Day ???????? on Saturday, it will be a beautiful day to spend time outdoors!

On Sunday, the heat will really arrive as temperatures climb into the low 30s with increasing humidity. By the late afternoon, dew point values could reach as high as 20 °C, which would make it feel more like the upper 30s.

On Sunday afternoon, a warm-sector trough — typically an area of lower pressure near the middle of a large area of warmer air — will begin pushing across southern Manitoba. This feature will be an area of concern for severe thunderstorm development later on Sunday.

The thunderstorm potential will be significant on Sunday thanks to ample heat and humidity at the surface and relatively cool temperatures aloft. MLCAPE values could exceed 2,000 J/kg in an environment with 20 to 30 knots of 0–6 km bulk shear. Veering wind profiles would support supercell structures, but moderate westerly forcing along the line would likely support upscale growth into the evening hours. Capping will be marginal — 700 mb temperatures are forecast to be around 9 °C — so there is uncertainty with where the southern end of the line would develop. Wind profiles aren’t overly backed at the surface, so this setup wouldn’t likely produce a widespread tornado threat. If a thunderstorm was able to tap into all the available energy, though, an isolated tornado threat could develop. More likely, these thunderstorms would be capable of severe hail and torrential rainfall.

The details of this could change between now and Sunday, but at this point it looks like Sunday will be the hottest day of the next few and bring an organized severe weather risk to the region for late in the day.

Long Range Outlook

A weak cold front will push through Sunday night easing the humidity across the region.

Through the start of next week, temperatures should sit closer to seasonal values with variable cloudiness as cooler air moves in under a slow-moving upper trough that moves into the region. Some showers could be possible, but right now it looks like the start of the week will be mostly dry for Winnipeg.

Today’s seasonal daytime high in Winnipeg is 25 °C while the seasonal overnight low is 13 °C.