A Slow Crawl Towards Seasonal Conditions Begins; More Rain Possible Next Weekend

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Southern Manitoba will see a very slow shift back towards more seasonal spring weather over the next week. Another storm system will impact the region this weekend, but its impact isn’t quite clear yet.

ECMWF 10m Winds and MSLP Forecast valid 12Z Tuesday April 26, 2022
A sprawling Arctic high will influence southern Manitoba right through the week.

The weather over the next few days will be dominated by a stubborn Arctic high lingering over the region. It sits on top of the province today, then gradually shift into NW Ontario over the next 36 hours. Southern Manitoba will continue to see a ridge of high pressure hang back across the region. This ridging will stick around until a developing storm system in the United States finally weakens it at the end of the week.

Its presence will be a bit of a mixed bag. On one hand, it will keep temperatures cool over the region. On the other, it will help deflect some weaker lows over the western Prairies away. This will keep conditions dry through the rest of the work week; a welcome outcome considering the flooding in the wake of the weekend’s storm.

For Winnipeg, this will mean that the city sees a fair amount of sunshine over the next couple days. Today’s high will be a few degrees above freezing, then increasing into the 5–10 °C range on Wednesday.

Thursday will bring some cloud to the region as an upper frontal wave pulls away from a low over the northwestern Prairies. There could be a few showers that skirt the region later in the day, but amounts would likely be very light

Skies will continue to be cloudy on Friday, this time due to another significant storm system taking shape in the United States.

Daytime highs will likely hover close to 10 °C both Thursday and Friday. Overnight lows will increase from several degrees below zero tonight to the mid-single digits by Friday.

Long Range Outlook

Unfortunately, it looks like southern Manitoba could be in for more rain to end the week. This system — a sort of “Utah Low” — won’t have quite as much energy as the weekend’s Colorado Low. It will still be a substantial storm in its own right, though.

There is, unlike the previous two storms, significant uncertainty with this one. Forecast models have been flopping around, placing the precipitation right across southern Manitoba, keeping it almost entirely south of the border, or shifting it into SE Saskatchewan and southwestern Manitoba.

So at this point, it’s still too early to say with much skill where the rain is going to show up. But there is pretty good agreement that this system will be capable of producing 25–50 mm of rain somewhere in the southeastern Prairies.

ECMWF 10m Wind and MSLP Forecast valid 12Z Sunday May 1, 2022
While there’s disagreement about where the rain will fall with this weekend’s system, all forecast models are producing a moderately strong low pressure system over the Dakotas and Minnesota.

If that rain did fall over the Red River Valley, it would be a significant concern. Not only is the ground very saturated in most areas, it would also coincide with the second crest of the Red River travelling northwards.

Should the rain fall further west, that would also be a concern. It would likely impact many areas that have seen substantial snowfall amounts over the past two weekends. This would help accelerate the melt and could present flooding risks in some of those areas as well.

So probably not a welcome storm in any situation. We’ll keep a close eye on it as it develops and have a full forecast later in the week.

If you have a property that experienced flooding issues this past weekend, it may be prudent to plan possible flood mitigation efforts in case this storm ends up impacting your area again.

Today’s seasonal daytime high in Winnipeg is 14 °C while the seasonal overnight low is 1 °C.

Cool Weather, More Precipitation Ahead for Southern Manitoba

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Cool weather continues this week with more precipitation in the forecast. Another batch of snow is heading to the province on Wednesday, followed by another winter storm on the weekend.

RDPS Precipitation Type & Rate Forecast valid 18Z Wednesday April 20, 2022
More snow is forecast across southern Manitoba on Wednesday.

Yesterday’s sunshine will be gone today as more cloud builds into the region. Warmer air moving in aloft will bring the cloud, but the southeasterly wind will keep it cooler near the ground. Winnipeg will see a high just above freezing today.

Some light snow will push into the region tonight ahead of the warm front. The snow should start sometime after 7PM and continue into the overnight period. Winnipeg should see around 2–4 cm by Wednesday morning with lesser amounts to the south. Lows will stay mild with the approach of warmer air; Winnipeg should dip to around 0 °C overnight.

On Wednesday morning, a second area of snow will blossom along the cold front and upper jet in North Dakota. This will push into the Red River Valley mid-morning, bringing a second batch of snow to the region. The precipitation should ease later in the afternoon with another 2–5 cm accumulation in the affected areas. The above-freezing temperatures will help compact and melt some of the snowfall as the day goes on. Winds will ease through the day as the low centre moves across the province. Today’s high will reach the low single digits.

Temperatures will dip down to around freezing again on Wednesday night. A few flurries will are likely as well. Northerly winds will pick up into the 30–40 km/h range overnight on the backside of the departing low.

RDPS 2m Temperature Forecast valid 21Z Thursday April 21, 2022
Cooler temperatures will continue on Thursday over the snow-covered ground in southern Manitoba and Saskatchewan.

A ridge of high pressure will slide into the province on Thursday, bringing gradually easing winds and some sunny breaks to the region. A high again in the low single digits will continue the below-normal temperature trend in the region. Temperatures will dip to around the freezing mark again on Thursday night with cloudy skies.

Long Range Outlook

Beginning on Friday, the region will start to be affected by a strengthening Colorado Low. While the low centre will stay well south in the United States, precipitation will move into the province already on Friday.

There’s a lot of uncertainty as to what exactly will fall over the province. The Canadian long-range model is trending warmer with most of the precipitation falling as rain. The American models are slightly cooler and trend towards a snow/ice pellet solution. The ECMWF model, on the other hand, sits somewhere in the middle. It has a mainly rain event for the Red River Valley, southern Interlake, and southeast corner of the province. For southwestern Manitoba, the Parkland, and northern Interlake, it produces a mix of ice pellets and snow.

This will be a multi-day system that impacts

ECMWF 2m Temperature and MSLP Forecast valid 18Z Saturday April 23, 2022
Weather models agree that a potent Colorado Low will lift into the Dakotas this weekend, bringing another winter storm to parts of Manitoba.

the region through Sunday. For areas in western Manitoba, it’s looking like it will be another considerable dump of snow with 20–50 cm possible in some areas. Western Manitoba is also looking like the most likely region to see fairly persistent precipitation through the event. Further east, the precipitation will come in multiple waves separated by relatively benign weather with perhaps a bit of drizzle.

In the waves that do move through, the rain or snow may be quite heavy at times, driven by convective elements. With the snow already on the ground across parts of the region, this could result in rapid snow melt. If you live in a property that has grading issues, you may want to move snow away from your home/foundation before the weekend to help minimize any potential overland flooding risks.

As with the last Colorado Low, this system will also likely see a dry slot wrap into southern Manitoba, most likely for the Red River Valley and areas east. This would result in a 6–12 hour break of benign, mild weather with the only real threat being a bit of drizzle.

As the low pushes off to the east on Sunday, some areas that have only seen rain may see some accumulating snow as well.

We’ll be keeping an eye on this system as it develops through the week and have more details in our Friday forecast!

Today’s seasonal daytime high in Winnipeg is 12 °C while the seasonal overnight low is 0 °C.

Cooler With Some Unsettled Weather Ahead

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The cleanup is underway across many areas of Manitoba that were pummelled with strong winds and 30–60 cm of snow. The weather will mostly co-operate over the coming days with cool temperatures and a bit more snow.

The entire eastern Prairies will see very cool mid-April conditions in the wake of the storm exiting the region.

RDPS 2m Temperature Forecast valid 21Z Friday April 15, 2022
The entire eastern Prairies will see very cool mid-April conditions in the wake of the storm exiting the region.

Lingering light snow will taper off today as the storm continues to wind down over the region. Winds will continue to be breezy out of the northwest at 30 gusting 50 km/h. Most notable today will be the temperatures; they will stay well below seasonal values with a high in Winnipeg near -5 °C. Skies should finally clear out this evening with temperatures heading to a low near -10 °C.

A high pressure system moving into the province will bring clear skies on Saturday. Temperatures will continue to be cool with a high near -5 °C. Lows on Saturday night will fall into the mid-minus teens. Another low pressure system approaching the province will spread cloud cover into the region by Sunday morning.

Winnipeg and area will see cloudy skies on Sunday with light snow moving in for the afternoon and evening. Highs will reach close to 0 °C with southeasterly winds picking up to 30 km/h.

A low pressure system will spread snow along the Trans-Canada Highway corridor on Sunday with 10–15 cm near the international easing to 5–10 cm for many areas south of the Trans-Canada Highway corridor.

RDPS 24-hour Snowfall Accumulation Forecast valid 12Z Monday April 18, 2022
A low pressure system will spread snow into southern Manitoba on Sunday.

This system will spread another swath of snow across southern Manitoba, with 10–15 cm near the international border easing to 5–10 cm for many areas south of the Trans-Canada Highway corridor. The main uncertainty with this system is how far north it will push; relatively sharp changes in snowfall totals will mean small shifts north or south can substantially impact the amount of snow a location will see.

Snow will taper off overnight with the sun repeating for Monday. Daytime highs to start the new week will hover around 0°C.

Long Range Outlook

Temperatures will moderate only slightly next week, partly due to a cooler air mass and partly due to the snow cover across the region. Highs should climb above freezing for next week, but conditions may also turn unsettled.

A progressive system is forecast to move through the region mid-week, potentially bringing another shot of snow to the region. Early model guidance suggests that 10–15 cm is possible with this system, but it’s early and lots can change between now and then. It will likely fall as snow, but there may be a little bit of rain mixed into it.

The region will see a couple quiet days, then for the weekend some weather models are suggesting that another Colorado Low system may develop. This one wouldn’t bring more snow to the region; rather, it would likely result in a surge of warm air northwards and could result in rain for the region. But, being so far out, it shouldn’t be taken as much more than hand-waving conjecture at this point.

As a generalization, beginning Sunday, it looks likely that the region will see some additional precipitation every 2–3 days for a while. By next weekend, the region is more likely to see rain than snow as warmer, almost summer-like, temperatures begin to push towards the region.

Today’s seasonal daytime high in Winnipeg is 10 °C while the seasonal overnight low is -2 °C.

Major Spring Storm On The Way For Southern Manitoba

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The most significant spring blizzard in decades is bearing down on southern Manitoba, but there’s nuance in the details. What follows is the best interpretation of the upcoming weather we can discern as of the time of writing. The forecast for this system may change on short notice, so be sure to keep alert of any updated forecasts or warnings from official sources.

GDPS Total Snowfall Forecast valid 00Z Saturday April 16, 2022
The Canadian GDPS model has slightly less snow than many of its peers, but shows well the very large area that will likely see 20–40 cm of snow. Other forecast models show accumulations over 25% higher than these values.

A complex storm system will bring a major spring blizzard to southern Manitoba beginning later today. While the broad strokes of this system have been quite clear for several days now — a testament to improvements in medium-range weather modelling over the past decade — there are many nuances to this system that will add layers of complexity to the forecast.

A pair of low pressure systems have merged overnight and now exist as a single potent low centred over western Nebraska and Colorado. This system is supported by two distinct features: an upper low over Iowa and a digging upper trough over Utah and Colorado. These two upper features and their evolution will guide the development of this system over the next 36 hours.

As this system pushes eastwards today, it will split into two surface lows: one that lifts northwards through the Dakotas through the day, and another that lingers in Colorado for a while longer before ejecting northeastwards into Minnesota. The northern low will be supported by the upper low, while the southern low will move along with the upper trough and strong frontal wave.

The first wave of snow will move into southern Manitoba this evening, supported by the northern low pressure system. This snow will likely be quite heavy with snowfall rates reaching as high as 3–5 cm/hr. This first shot of snow will lift from North Dakota into SE Saskatchewan and SW Manitoba, then spread eastwards across the Red River Valley and into NW Ontario. By the end of Wednesday, it’s likely that 20–40 cm of snow will have fallen over the southwestern corner of the province and the western escarpment/Riding Mountains, and 10–20 cm of snow in the Red River Valley and southeast corner of the province.

As the day progresses on Wednesday, the precipitation lifts northwards as the northerly surface low stalls out near the MB/ND/MN borders. It looks quite likely that this system’s dry slot will spread into southern Manitoba, bringing an end to most of the snow over the Red River Valley and southeastern Manitoba. If this happens, the region would see a reprieve from the snow later Wednesday through the night, but with a decent chance of [freezing] drizzle or few flurries through that period. The snow will continue elsewhere in Manitoba, albeit comparatively lightly with general accumulations overnight of 5–10 cm. Terrain features will continue to see enhanced accumulations with 10–20 cm possible, particularly closer to Lake Manitoba and the Riding Mountains.

On Thursday, the Colorado Low will become dominant in NW Ontario, producing heavy snow that will spread westwards across the Interlake into western Manitoba through the day. Light to moderate snow will spread back through the Red River Valley for Thursday. The stalled surface low in Manitoba will collapse as the Ontario low strengthens, and the strongest winds will shift eastwards into the Red River Valley with sustained northerlies of 50–60 km/h. Close to 5 more centimetres of snow is likely for Winnipeg on Thursday.

The snow will begin to ease on Thursday night, then clear out of the region through Friday.

RDPS 10m Wind Forecast valid 15Z Wednesday April 13, 2022
This storm will bring moderate to strong north-northeast winds to parts of southeastern Saskatchewan and southern Manitoba on Wednesday morning. The winds will ease slightly and shift into the Red River Valley on Thursday.

Regarding the wind and blowing snow, the stalling of the low near the MB/ND/MN border and timing of the NW Ontario low takeover will result in full-fledged blizzard conditions being most likely in SE Saskatchewan into SW Manitoba. Lighter winds are likely in the Red River Valley, and the peak forecast winds for this system have subdued slightly. That said, especially in the first wave, white-out conditions will be possible in heavy snow.

So, by the time the snow tapers off on Friday, it still look likely that 30 to 50 cm of snow will fall widespread across southern Manitoba. It will be a fairly persistent event from areas in SE Saskatchewan through southwest and western Manitoba as well across the Interlake. It looks like the situation in the Red River Valley will be different though, with multiple waves of snow. Winnipeg and area will likely see a wave of very heavy snow on Wednesday morning taper off later in the day with as much as 15–25 cm possible. Snow will likely ease for the city Wednesday evening/overnight with a chance of [freezing] drizzle. The wind will pick up on Thursday as more snow moves back into the region; the Winnipeg area will likely could see as much as 5–10 cm of snow.

Lighter amounts will fall to the south, but a heavier band of snow the north will give 10+ centimetres to the Interlake and other parts of central Manitoba.

The snow, wind, and blowing snow will begin to ease Thursday night, with conditions continuing to improve on Friday. For Winnipeg, this means that about half of the expected snow will likely fall on Wednesday alone, with the other half or so coming over the following 24–36 hours as a separate wave of snow. It will still amount to quite a bit, but it won’t be the 3-day raging blizzard like it looked like it could be even a day ago.

Temperatures will hover just above freezing today and tomorrow, then fall below freezing on Thursday.

Long Range Outlook

Cooler temperatures will stick around for the weekend with sub-freezing highs and seasonably cool lows. It should be a relatively quiet period for several days after this event, giving plenty of time to clean up after this storm.

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