Wet, Unsettled Weather Ahead for Winnipeg

A slow-moving complex of low pressure systems in the northern United States will spread cloud cover and waves of showers across southern Manitoba through the coming days.

ECMWF Total Accumulated Precipitation valid between 00Z Thursday September 22 and 00Z Monday September 25, 2023
Multiple waves of rain will move across southern Manitoba in the coming days, with the potential for some higher rainfall totals by Sunday evening.

Waves of rain will move through the Red River Valley over the coming days, but it will at least be relatively mild through the weekend. Despite the unsettled weather, daytime highs will climb to around 20 °C over the coming days. The cloud cover will also keep nights warmer with lows dipping down into the mid-teens. Throughout next few days, the wind will also be consistently out of the east, often in the 20 to 30 km/h range.

The rainfall forecast is a bit tricker than all the other elements, largely due to the complexity of the interacting systems south of the border and how thunderstorm activity will evolve as this disturbance matures.

Today, Winnipeg will likely see on and off showers continue through the morning, then things will have a chance to dry out a bit as the showers shift towards the west. Another wave of rain will push into southern Manitoba overnight and persist into Saturday morning. Things should mostly dry out on Saturday afternoon, but a few pop-up showers may be possible if the sun peeks out a bit and warms things up, or depending on the timing of this system, the cloud and rain could drag on later into the day.

The rain will calm down for Saturday evening, but then another broad area of rain will push northwards into Manitoba overnight, this time as the entire system in the United States begins shifting northwards. More rain will likely move through, and then lingering showers or drizzle could persist through the day on Sunday.

Long Range Outlook

The rain should taper off for Monday, but the region could see a lot of leftover cloud cover through the day. By Tuesday, the sun should begin poking out again and Winnipeg will see several pleasant days with highs in the low 20s and lows in the low teens.

Today’s seasonal daytime high in Winnipeg is 16 °C while the seasonal overnight low is 4 °C.

Seasonal Temperatures With A Chance of Unsettled Weather

Seasonal temperatures will continue for much of the week across southern Manitoba, but a passing low pressure system on Saturday may replace sunshine with unsettled conditions.

RDPS 2m Temperature Forecast valid 21Z Thursday September 14, 2023
A low pressure system crossing Manitoba will bring warmer weather to the region on Thursday.

A collapsing upper ridge will gradually push into Manitoba as it weaken over the next couple days, bringing plenty of sunshine but not too much warmth. High temperatures in Winnipeg will sit close to 20 °C over the next couple days with a few clouds on Wednesday afternoon. The winds will be light on Tuesday, but could reach up to 30 km/h on Wednesday afternoon.

More cloud will move into the region on Wednesday night as a low pressure system crossing the northern Prairies pushes a warmer air mass into the region. Some showers might move through the region overnight Wednesday as this warmer air pushes in. This warmer air mass will help with overnight lows; Wednesday night will likely only drop into the low teens, compared to a low near 5 °C tonight.

On Thursday, highs temperatures will climb towards the mid-20s across southern Manitoba. Instability will grow through the day as a warm-sector trough pushes into the Red River Valley. As a result, there will actually be a small chance of some showers or thunderstorms later in the afternoon and early evening. With only around 500 J/kg of MLCAPE and 20–25 knots of bulk shear, any severe weather is highly unlikely. 

A cold front will sweep through on Thursday night, bringing seasonal temperatures back to the region on Friday.

Long Range Outlook

The region will see near-seasonal temperatures along with a mix of sun and cloud into the weekend. There will be a slight chance of showers on Friday night as some wrap-around precipitation moves across the region as an upper low exits the region.

Some warmer weather will likely push in to start next week with daytime highs climbing back towards the mid-twenties.

Today’s seasonal daytime high in Winnipeg is 19 °C while the seasonal overnight low is 7 °C.

Showers and Smoke Today, Pleasant Week Afterwards

Winnipeg will see morning showers and widespread smoke today as a low pressure system passes by the region. Much more pleasant weather will return for the rest of the week and the start of school.

ECMWF 6-hour Precipitation Accumulation Forecast valid 18Z Tuesday September 5, 2023ECMWF 2m Temperature Forecast valid 18Z Tuesday September 5, 2023
Some lingering [thunder]showers will push off into Ontario on Tuesday morning, leaving behind a relatively cool day with highs near the 20 °C mark across southern Manitoba.

After the night’s heavier rain, a few showers or thunderstorms will drift northeastwards early this morning, clearing out of the Red River Valley as a low pressure system moves into Ontario. In its wake, widespread smoke will linger through much of southern Manitoba. This will give very poor air quality to the region and has resulted in a special air quality statement from the MSC. Winnipeg will likely see mainly cloudy skies today, though some late-day sun is possible. It will be a cool day, though, contrasting with the weekend heat as the daytime high only climbs to around 20 °C. Breezy northerly winds will abate this evening as skies clear. Temperatures will head down to a low near 10 °C.

Heading into the rest of the week, a steady and relatively stable pattern develops for the Winnipeg area. With a generally zonal flow aloft and disturbances tracking well to the north, conditions will trend fairly sunny throughout the Red River Valley. Smoke may be noticeable on a couple days through the rest of the week, but it’s unlikely to get anywhere near as bad as Tuesday’s conditions. And temperature-wise, there’s no complaints for the rest of the week with near-seasonal values expected. Highs will sit in the low 20s with lows dipping into the upper single digits.

Long Range Outlook

It currently looks like more of the same in the Red River Valley for the weekend and start of next week. Smoke will be the only wildcard in the long-range forecast, so we’ll keep our eyes peeled in case the potential for another bout of poor air quality arises.

After today’s smokey weather clears out, enjoy the beautiful late-summer weather!

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

Cooler, Cloudier Weather Gives Way to Pleasant Weekend

Winnipeg will see a much cooler and comfortable day today with cloudier conditions and a chance of showers. For the weekend, a building upper ridge will bring sunshine as warmer weather builds into the region.

RDPS 2m Temperature Forecast valid 21Z Friday August 25, 2023
Seasonal temperatures will return to southern Manitoba as a broad area of high pressure builds across the Prairies.

Today will be a marked departure from yesterday’s hot and humid weather that led to an outbreak of severe thunderstorms across southern Manitoba, including a potent storm that pummelled NE Winnipeg. With the system responsible for that weather off to our east, today will bring cooler northwest winds that will usher in cloudier skies with a chance of some scattered showers. Temperatures should reach a high near 20 °C with northwest winds up to 30 gusting 50 km/h. Skies will clear out later this afternoon, then the wind will die off and temperatures will head to a low on the cooler side of around 10 °C.

For the weekend, Winnipeg should see mainly sunny skies on Saturday with light winds and a high in the low 20s. On Sunday, warmer weather will push in with highs in the mid-20s. Some cloud is likely in the afternoon as a trough of low pressure moves through. This feature might bring a chance of a thunderstorm with it, but it’s looking a bit uncertain at the moment. A cold front will slump southwards overnight as temperatures head to a low in the mid-teens.

The region will likely see some haze through the weekend as well as wildfire smoke once again makes its way into southern Manitoba.

Long Range Outlook

Next week will start off with a couple seasonally-appropriate days; both Monday and Tuesday will bring highs in the 20 to 25 °C range with partly cloudy skies. By mid-week, warmer weather with highs in the mid-20s will return to the region, but we could see another chance for showers or thunderstorms in the latter half of the week.

Today’s seasonal daytime high in Winnipeg is 23 °C while the seasonal overnight low is 10 °C.