Heat Returns, Along with a Risk of Thunderstorms

The heat will return early this week as temperatures climb up to the thirty degree mark. This warm and humid air mass will also bring another risk of thunderstorms to southern Manitoba on Tuesday.

Hot weather is in store for southern Manitoba early this week
Hot weather is in store for southern Manitoba early this week

This Week

Today will be a hot one in southern Manitoba. Temperatures are expected to climb into the low thirties in most areas. The humidity will begin to climb as well, with dewpoints reaching the upper teens in most areas by late Monday – although locally higher dewpoints will be possible. Despite these hot and humid conditions it doesn’t appear that we’ll see any storms today. The atmosphere is expected to be capped, preventing thunderstorms from developing. There is a slight risk of storms overnight, but conditions don’t look particularly good for widespread development.

Tuesday will be the more interesting day storm-wise, as humidity increases further. A low pressure system is expected to sit over southern Manitoba by midday Tuesday, maintaining a south to southeast surface flow over the Red River Valley and southeastern Manitoba. Instability will be high with the hot and humid conditions, while wind shear is also strong because of the approach of a strong upper-level trough. These conditions should be favourable for the development of severe thunderstorms. High temperatures should end up near 30C with the humidex in the upper thirties. Skies will be mainly sunny before storms begin to develop.

A strong cold front is expected to slice through southern Manitoba on Wednesday morning. This front will drop temperatures down to near the 20C mark. The front will also take advantage of the lingering humidity in the atmosphere to produce shower activity over most of southern Manitoba. Following the frontal passage, it will become quite gusty as well, with northerly winds of 40 km/h gusting to 60 km/h.

Long Range

It appears that temperatures will begin to rebound later this week following the passage of that cold front on Wednesday. Temperatures approaching the 30C mark may be possible again by the weekend – although models are still unclear as to how long and intense this next burst of heat will be.

The Summer of Storms Continues

Whether you’re in the middle of a home renovation that involves taking off part of your roof as I am[1], trying to harvest fields, or just trying to string together a few dry days for a camping trip, this summer continues to challenge as the threat for thunderstorms continues across the Red River Valley.

Today will be a hot one across southern Manitoba as a light southerly wind taps into a warmer air mass to our south, drawing daytime highs up to around the 30°C mark in Winnipeg. Skies will be fairly sunny until late in the day when cloud cover begins thickening up from the west.

Estimated precipitation totals from the RDPS for Wednesday night through Thursday.
Estimated precipitation totals from the RDPS for Wednesday night through Thursday.

A cold front sweeping into Manitoba through the evening and overnight will once again spread showers and thunderstorms into Manitoba. There will be a slight risk of severe thunderstorms in the late afternoon and evening hours to the north and west of the Red River Valley. This severe thunderstorm threat will shift into the Red River Valley late in the evening & into the overnight period. These thunderstorms will pose a primary threat of large hail and damaging winds.

The unsettled activity will persist into Thursday morning with more showers and thunderstorms possible as the upper-level support for this disturbance rolls through. Winds will pick up out of the northwest to about 20 km/h as skies begin to clear for the afternoon. Temperatures will be a just slightly cooler with a high near 27°C, but the overnight low on Thursday night will be much cooler at around 13°C.

Friday will continue the cooling trend in temperatures as another cold front pushes through, limiting daytime highs to the low 20’s. Mixed skies will be in place alongside a slight chance of some afternoon showers and gusty north to northwesterly winds of 20-30 km/h.

Winnipeg’s seasonal daytime high is currently 25°C while the seasonal overnight low is 12°C.

  1. Anyone? Just me?  ↩

Warm With A Risk of Thunderstorms

This week will be a warm one, with temperatures frequently reaching the upper twenties. This heat will be accompanied by some humidity, which will prompt a renewed risk of thunderstorms.

A warm front will be located in southern Manitoba today
A warm front will be located in southern Manitoba today

This Week

Today will be a hot one in southern Manitoba. Temperatures will be in the upper twenties to near 30C, with increasing humidity making it feel more like the mid thirties. Winds will generally be light, with the direction varying between easterly and southerly depending on your location. The heat and humidity today will prompt a risk of thunderstorms. Some storms may be marginally severe, as moderate instability but weak wind shear characterizes the environment. Any severe storms could potentially produce hail around nickel size and wind gusts to 90 km/h – although the odd storm may slightly exceed those values. Storm coverage is not expected to be very widespread, so many people may not see any activity.

A weak cold front will pass through early Tuesday, cooling us down a little bit. High temperatures on Tuesday will generally be in the mid twenties, with some lingering humidity making it feel closer to 30. A risk of thunderstorms will once again be present due to that lingering humidity, but any storms that develop should be non-severe. Winds will be northerly at around 20 km/h.

Slightly warmer conditions are expected again for Wednesday as temperatures climb into the upper twenties with light southerly winds. Skies are expected to be mainly sunny, making for quite a nice day!

Long Range

The long range forecast shows a stronger cold front passing through southern Manitoba later this week, likely on Thursday or Friday. Depending on the timing of this front, it may pose another risk of thunderstorms. Following the frontal passage we’ll see somewhat cooler conditions, likely persisting into the weekend.

Slow-Moving Pacific Low Brings Stormy Weather to Manitoba

A slow-moving low pressure system that has meandered into the Prairies from the west coast will very gradually make its way through the province over the coming few days, bringing with it numerous chances for showers and thunderstorms.

The coming few days will be rather unsettled over the Red River Valley, however there’s no guarantee any one location will end up seeing all that much rainfall as multiple rounds of showers and thunderstorms swing across the region. Given that the next three days will all be under the influence of the same system, I’m going to break down the forecast in a slightly different way than usual and cover the weather elements individually instead of talking about each day.


Temperatures are expected to climb into the mid-20's on Thursday in the Red River Valley.
Temperatures are expected to climb into the mid-20’s on Thursday in the Red River Valley.

First off, the temperatures. Today and Thursday will both be days with near-seasonal high temperatures of about 25°C. Overnight lows for today & tomorrow will be slightly warmer than normal with a lows of 16-17°C.

A cold front will sweep through on Thursday night, ushering in cooler temperatures for Friday with a daytime high near 22°C and an overnight low near 13°C.

Cloud Cover & Wind

Skies will become incrementally more cloudy over the next three days with a mix of sun and cloud expected today in Winnipeg, fairly cloudy skies with a few sunny breaks on Thursday, and mainly cloudy skies on Friday.

Winds will also be fairly light over the coming few days; expect easterly winds between 10-20 km/h today & tomorrow, then a shift to northwesterlies for Friday with slightly breezier conditions as winds climb to around 30 km/h.


This is the much harder thing to nail down in today’s forecast. The Red River Valley will be dealing with several waves of precipitation over several days, much of it convectively driven which automatically injects some uncertainty into the forecast. Here goes as best an overview as we can!

Variable amounts of rainfall are expected over the next 3 days in the Red River Valley with more confident rainfall amounts in Central Manitoba and North Dakota.
Variable amounts of rainfall are expected over the next 3 days in the Red River Valley with more confident rainfall amounts in Central Manitoba and North Dakota.

Wednesday: There will be a chance of showers or thunderstorms today as two areas of convection pass by to the south and north of the Red River Valley. Conditions will likely remain fairly dry, however there is the off chance of some areas being clipped by either of these systems. A more organized system will develop tonight as the frontal wave associated with the Pacific low moves through the region and the low itself moves in.

Wednesday Night/Thursday: A risk of elevated convection will be in place tonight into Thursday morning. There’s still uncertainty with exactly where the storms will develop, but it’s safe to say that the entire Red River Valley is at risk of seeing thunderstorms and rain. Some of these storms may be severe. We’ll produce a convective outlook image once the situation is a little more clear.

Then the threat for thunderstorms returns on Thursday afternoon as a cold front sweeps across the Red River Valley and the low slumps from Western Manitoba into the Red River Valley. It looks, at this point, that any storms that develop on Thursday afternoon could be strong to severe.

Friday: The main low will move through on Friday, bringing widespread shower activity. An isolated thunderstorm or two is possible, but they are not expected to be severe should they develop.

Long Range

Briefly looking ahead to the weekend, it appears that Saturday could bring some more scattered showers with a chance of an isolated thunderstorm. Sunday is looking like the day where things return to slightly more pleasant conditions with the sun returning and temperatures climbing back into the mid-20’s.

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