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.
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.
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
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.
Cooler weather and scattered showers will settle into the Red River Valley today behind the low pressure system that brought multiple rounds of thunderstorm activity to Southern Manitoba over the past several days. The cool weather will give way to more seasonal warmth by the end of the weekend, but with the return of warmer weather will come another chance for thunderstorms in the first half of next week.
The weather in Winnipeg over the coming two days will be created by an upper-level low pressure system stalled out over east-central Manitoba. Both today and tomorrow will see fairly cloudy skies, likely mixed to mainly cloudy, alongside the chance for scattered showers. Today will present a better chance for showers than tomorrow, but even then the activity will likely be fairly light and scattered. Winds will be out of the west to northwest at around 20-30 km/h during the days and lighter at night. Daytime highs will be below-seasonal at just 21 or 22°C, however the overnight lows will be right on the mark for this time of year at 12 or 13°C.
Scattered showers are expected over southern Manitoba over the next two days.
The cloud should clear out on Saturday night as the upper low finally trundles out of the region and a ridge of high pressure builds in.
Sunday will be a comparatively pleasant day with mainly sunny skies, although the beginning and end of the day may be bookended by some clouds. Daytime highs in Winnipeg & the Red River Valley will be fairly warm at 26 or 27°C. With warmer air in place, the overnight low on Sunday night will also be milder at around 14 or 15°C.
Long Range
Early next week is looking mild, but the weather trend of 2016 continues with another chance for showers and thunderstorms returning sometime late Monday into Tuesday. At this point, it appears that this will appear as a round of thunderstorms on Monday night, but it’s still quite early and the timing of the system could easily change.
The long-term pattern continues to show an unsettled pattern with a couple days of showers and instability followed by a few days of drier weather. There are hints of attempts to produce more prolonged periods of dry weather in 1-3 weeks from now, but models seem to be struggling to establish the ridging required. So at this point, it looks like more of the same for the coming weeks, which is not likely the news that many farmers wish to hear heading towards harvest.
Winnipeg’s seasonal daytime high is currently 25°C while the seasonal overnight low is 12°C.
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
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.
Precipitation
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.
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.
