Cool, Wet Weather Ahead for Winnipeg

A slow-moving low pressure system will bring wet weather to southern Manitoba as rain showers transition to snow mid-week.

NAM Precipitation Type and Intensity Forecast valid 00Z Wednesday April 17, 2024
Manitoba will be under the influence of a complex weather set-up spanning from the central United States the fringes of Canada’s Arctic regions this week.

It will be a cool and wet few days in Winnipeg this week as moisture streams northwards out of the United States and brings rain showers to southern Manitoba. This is a large system that spans the Canadian Prairies and into much of the American Plains and mid-west.

The broad view of this system starts with a potent Colorado Low in the United States which is supporting a broad area of rain showers and waves of thunderstorms. This system will stream moisture northwards, where it will then be captured by an upper low over the Prairies and drawn into the northern Prairies.

The result of all this will be waves of rain showers that lift northwards out of the United States into southern Manitoba, pushing towards a feature called a deformation zone that will be aligned north-south along the Saskatchewan/Manitoba border. These are upper-level features that act as walls in the atmosphere; the wind does not move through them, and instead spreads out along them.

As the rain meets this feature, it will spread out into a broad area of rain over western Manitoba. This feature will gradually drift east later today and overnight as colder air slumps into the region. This precipitation will likely become mixed with snow overnight as it drifts east to the Red River Valley.

By Wednesday, it could be rain or snow falling as the band of precipitation slowly crosses the Red River Valley. Much of the precipitation should come to an end in Winnipeg later on Wednesday; by this point, the region will have seen anywhere from 10 to 30 mm of precipitation, with a chance that localized areas see even higher amounts. In Winnipeg, storm total precipitation will likely fall in the 15 to 25 mm range.

Temperatures throughout this period will fall from a high in the low teens today to high single digits on Wednesday. A cold front will sweep through on Wednesday night, drawing wrap-around snow into southern Manitoba and bringing even colder air into the region.

Daytime highs on Thursday will struggle into the low single digits with bands of wrap-around snow moving through the region. It will be a windy, cool day that comes as an unpleasant turnaround from the beautiful weather on the weekend.

A Note On Confidence

This system is large and complex, and even at this point there is notable uncertainty with how it will develop; in particular, the complex interactions of the Colorado Low and the thunderstorm activity it triggers in the United States could have knock-on effects that impact the weather here. The evolution of the moisture supply, the positioning of low-level jets, how the deformation zone evolves…these all could notably impact the when, where, and how much of these forecasts.

I’ve shared by best effort at a forecast here with full knowledge that I might think “I should have made a different decision in my forecast” by this evening. This should give you a good idea of the general weather pattern over the next few days, but I recommend keeping up to date on the latest forecasts for your area over on the MSC’s weather forecasts page.

Long Range Outlook

This system will finally start moving out of the region on Friday, leaving behind sunny skies for the weekend. Daytime highs will climb back into the low teens over the weekend, leading into a pleasant start to next week with near-seasonal temperatures and plenty of sunshine.

Today’s seasonal daytime high in Winnipeg is 11 °C while the seasonal overnight low is -2 °C.

Beautiful Weekend Ahead for Winnipeg

A push of warm air will bring beautiful spring weather to southern Manitoba this weekend.

3km NAM simulated RADAR reflectivity valid 04Z Saturday April 13, 2024
Elevated showers with the risk of a thundershower are possible overnight Friday across southern Manitoba.

A low pressure system lifting from northern Alberta into the southern Arctic will drag a warm front across the southern Prairies. This will spread seasonably mild temperatures into the province for the weekend.

For today, though, a ridge of high pressure over the province will bring partly cloudy skies with a high near 10 °C.

The warm front will push east across Saskatchewan today, pushing into southern Manitoba into Saturday morning. This will bring cloud cover into the region and keep overnight lows mild near +5 °C. As this warm front tracks into Manitoba, there may be enough mid-level instability for scattered showers or thunderstorms overnight into Saturday morning.

Once the morning cloud clears out, Saturday will be a pleasant day across southern Manitoba with partly cloudy skies and daytime highs in the upper teens or low 20s.

Temperatures will dip to around 5 °C again on Saturday night.

A ridge of high pressure that moves into the region on Sunday will bring sunny skies and a high in the upper teens.

Long Range Outlook

Next week will bring a low pressure complex to the Canadian Prairies and American Plains, driven by a potent Colorado Low. This system will bring showers, thunderstorms, and snow to various parts of the southern Prairies beginning on Monday and lasting through Thursday.

The heaviest snow will likely spread from central Saskatchewan into central Manitoba where anywhere from 40 to 60 cm is possible. To the south of this, many areas will see varying amounts of a mix of precipitation. It will trend more towards snow in Saskatchewan while southern Manitoba sees a greater mix of rain and snow.

Winnipeg is looking to be tucked away in a comparatively warm pocket that includes the Red River Valley and southeastern Manitoba. Current outlooks would suggest that this area mainly sees a few waves of rain and drizzle, with snow holding off until lighter wrap-around snow moves through as the system leaves the region.

This will be a complex system with evolving forecasts over the coming days. You can check the latest forecasts on the Meteorological Service of Canada’s website.

Today’s seasonal daytime high in Winnipeg is 9 °C while the seasonal overnight low is -3 °C.

Mild With a Chance of Showers

The warm spring weather continue in Winnipeg this week, but a passing low pressure system on Wednesday will bring a chance of showers to the region.

ECMWF 24hr. Precipitation Accumulation Forecast valid 18Z April 11, 2024
Rain showers are possible across southern Manitoba from Wednesday afternoon through Thursday night.

Temperatures will stay warm in Winnipeg through the rest of the week as more mild Pacific air spills across the southern Prairies. Daytime highs will hover in the low to mid-teens this week with lows in the 0 to +5 °C range.

While today will be mainly sunny, clouds will move in tonight as a low pressure system moves into southern Manitoba from central Saskatchewan. This system will support an area of showers that develops on Wednesday afternoon near the Saskatchewan/Manitoba border that drifts southeast into the evening. The chance of showers will last through the night, then taper off on Thursday morning as the low moves into Ontario.

Behind the low on Thursday, cloud cover will slowly break up as moderate northwest winds develop. By the afternoon, Winnipeg should see clearing skies with northwesterlies into the 30 to 40 km/h range. A ridge of high pressure will move in on Thursday night, bringing clear skies and light winds.

On Friday, the ridge will depart to the east and another low pressure system will begin its trek across the Prairies. This will bring increasing southeast winds with sunny skies giving way to late day cloud. There will be a chance of showers on Friday night as a warm front moves across the province.

Long Range Outlook

Saturday will bring the warmest weather of the year thus far to the Winnipeg area. With the warm front through and no snow cover left, daytime highs should be able to climb into the upper teens or low 20s with west-southwest winds. There could be a chance of a shower on Saturday evening as a cold front swings through with the passage of a low pressure system.

Sunday will bring cooler, but still mild, weather to the region. Daytime highs should sit in the mid-teens with breezy northwest winds and mixed skies.

Heading into next week, many forecast models suggest that a potent Colorado Low will develop and move towards the province. It’s too early to say anything definitive at this point, but this system could bring a broad swath of notable rain and/or snow to much of the eastern Prairies as it moves through. This storm could bring dangerous winter storm conditions to parts of the eastern Prairies; at this point it looks like much of the worst of the storm will move through eastern Saskatchewan and western Manitoba, but we’ll be sure to keep an eye on it as it develops.

Today’s seasonal daytime high in Winnipeg is 8 °C while the seasonal overnight low is -4 °C.

Sunny and Warm This Weekend in Winnipeg

A stagnant pattern over the region will bring sunny skies and warm weather to Winnipeg for the rest of the weekend.

RDPS 2m Temperature Forecast valid 21Z Friday April 5, 2024
Mild temperatures will continue to wash over the southern Prairies this weekend.

A slow-moving upper ridge over the the province and a stalled surface low in Montana will result in little change to the weather in Winnipeg this weekend.

In the days ahead, the region will see sunny skies with daytime highs warming from the low teens into the mid-teens. Overnight lows will hover near or just above freezing.

Winds will strengthen out of the southeast into the 20 to 30 km/h range today, stay steady tonight, then increase to 40 gusting 60 km/h on Saturday. The winds will ease on Saturday night back into the 20 to 30 km/h range and shift easterly for Sunday.

Long Range Outlook

Monday brings the partial solar eclipse to the region, and unfortunately the region may struggle with cloud cover through the day. A low pressure system crossing the American Plains will spread thick cloud cover all the way through North Dakota and it’s likely that it will spill into southern Manitoba. At this point, it’s unlikely that skies will be overcast, but the region will likely have at least a mix of sun and cloud.

Skies will clear out Tuesday, leaving partly cloudy skies for much of the rest of the week. Temperatures will continue to be mild with highs in the 10 to 15 °C range and lows hovering near the freezing mark.

Today’s seasonal daytime high in Winnipeg is 7 °C while the seasonal overnight low is -5 °C.