Tag: Above-Normal Temperatures

Weekend Brings Start to Spring Melt

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A strong upper ridge will spread a much warmer air mass into the eastern Prairies this weekend, marking the start of a widespread spring melt.

GOES-16 True Colour RGB Image of the Southern Prairies valid 0019Z Friday April 7, 2023
True-colour satellite imagery from Thursday evening reveals a widespread snowpack (white) across much of southern Saskatchewan, southern Manitoba, and North Dakota.

As we mentioned on Tuesday, southern Manitoba will see a much warmer air mass move into the region this weekend as upper ridging persists over western Canada. While this feature will produce plenty of warm air that will head east, the biggest wrinkle in the whole thing is the extensive snow pack across southern Manitoba and North Dakota.

This deep layer of snow will keep the surface cooler and help support an inversion across the region. An inversion is when temperature warms as you go up instead of cooling. This can effectively limit the ability for the warmer air over top of the surface to reach down to the ground.

Mild air will certainly stream into the province this weekend. Temperatures at 850 mb — about 1.5 km above the ground — will climb from around 0 °C on Saturday to warmer than 15 °C on Tuesday into Wednesday. Now, if we had full sunshine and dry, bare ground, that could result in daytime highs climbing from the low teens into the upper 20s. But the snow will absolutely keep temperatures much cooler than that.

850mb temperature anomalies — how much warmer or colder than the seasonal average values — show the entire Prairies seeing a seasonably mild air mass by the end of the weekend (left image). Heading into next week, though, the air mass becomes unseasonably warm over the southeastern Prairies (right image). How this abnormal warmth will interact with the existing snowpack is unclear at this time.

The other factor to pay attention to that will dramatically impact how quickly the snow melts will be the dew point temperature. When the dew point is below freezing, it is easy for water that is draining through the snowpack to re-freeze within it. But when the dew point climbs above freezing, that process becomes much harder and the rate the snow pack will melt at increases. The dew point will likely climb to the positive side of freezing this weekend, then increase several degrees above freezing next week as the warmer air pushes into the region.

The last factor to take into account is what all this water that’s melting out of the snow will do. With warming temperatures aloft and a strong inversion, that moisture will be trapped near the surface. This could result in the development of fog and low clouds as the melt picks up, which would also work to reduce potential high temperatures and produce cloudier conditions that really lock temperatures fairly close to freezing. It’s simply impossible to tell at this time if that will happen this weekend, but it’s a possibility to keep in mind.

So all that said, what can we expect?

After a cold start to the morning, temperatures will climb to a high near freezing this afternoon with a light southerly wind. Temperatures will dip back down into the minus teens tonight, the the warmer air mass begins building in this weekend.

Temperatures will climb to a high a few degrees above freezing on Saturday and Sunday with light southerly winds continuing. Overnight lows will be much warmer, just dipping below freezing overnight on both nights. Conditions will likely be sunny, but particularly beginning Saturday night there may be a chance of seeing widespread fog or low cloud develop. If it does, it could persist through Sunday and into the start of next week.

The snowpack will likely begin to melt at a faster rate as dew point values climb above freezing on the weekend.

Long Range Outlook

Next week will start off with a very warm air mass moving over the region, with the large question mark of how the near-surface layer will interact with the snowpack. Continued southerly winds will likely serve to reinforce the low-level inversion, but the sheer magnitude of the warm air will likely result in either (a) temperatures climbing towards 10 °C or even warmer in any areas with an eroded snow pack, or (b) widespread development of low cloud that results in near-surface temperatures again only a few degrees above freezing.

It’s simply too early to know exactly how that will go at this point, but we’ll be keeping an eye on things through the weekend.

One thing for sure is that substantial amounts of snow will melt next week, both in southern Manitoba as well as North Dakota. The water may appear relatively quickly, so we encourage anybody in areas that may need to be concerned about flooding to keep a close eye on updated flood conditions and forecasts. Moderate to major flooding is possible along parts of the Red River in North Dakota and Manitoba. Depending on the rate of snowpack melt in Manitoba, overland flooding may also be an issue beginning next week.

Fortunately, there is little risk for any notable precipitation across southern Manitoba over the coming week.

Today’s seasonal daytime high in Winnipeg is 7 °C while the seasonal overnight low is -4 °C.

Milder Weather Returns for the Weekend

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Winnipeg will see milder weather return today and near-seasonal conditions this weekend. Conditions will turn next week, though, as bitterly cold Arctic air descends into the Prairies.

RDPS Forecast 2m Temperature valid 21Z Friday February 17, 2022
Relatively mild conditions will move into the Red River Valley today with daytime highs near the freezing mark.

A low pressure system crossing the northern Prairies has brought a stiff southerly wind and warming temperatures to southern Manitoba today. With southerlies up near 40 gusting 60 km/h, temperatures rose through the night and will continue through the morning. The city should see a high near the freezing mark this afternoon as winds ease and turn westerly-northwest.

The region will see mixed skies today and there’s a slight chance of some light snow. Most of the precipitation will likely stay well north of Winnipeg, but some scattered areas of light snow might hang on along the trough as it moves through. Even if any precipitation does make it into the Red River Valley, no notable accumulation is likely.

A lingering chance of flurries will linger into the night as temperatures dip into the -10 to -15 °C range. The cloud cover should break up a bit overnight with easing winds.

On Saturday, more cloud will move back into the region as another weak low pushes into the region. There will be a slight chance of flurries through the day as temperatures rebound back to a high near -5 °C.

A band of light snow will likely work its way across the region on Saturday evening as a cold front sweeps into the region. A couple centimetres is possible as northerly winds pick up through the night. Temperatures will dip into the -10 to -15 °C range by Sunday morning.

To wrap out the weekend, northerly winds will continue as colder air pushes into the region. Some sun should reappear on Sunday with a below-seasonal high near -12 °C or so. More cloud will push into the region on Sunday night as another low approaches the region. Temperatures will be a bit cooler, though, with a low near -20 °C. Some light snow will push towards the region for Monday morning.

Long Range Outlook

Winnipeg will likely see some light snow to start off next week. The high temperature will climb back to around -10 °C, but a cold front sweeping through later in the day will usher in northerly winds that bring a substantial change to the region.

Skies will clear as the system leaves on Monday night, and much colder weather will move into the region in its wake. Lows will dip into the -25 to -30 °C on Monday night. Heading into the rest of the week, daytime highs will drop to close to -20 °C with some -30 °C lows possible much of the week. 

Temperatures will begin to moderate slightly on Friday, with a more marked push towards seasonal values beginning next weekend.

Today’s seasonal daytime high in Winnipeg is -8 °C while the seasonal overnight low is -18 °C.

More Warm Weather Ahead for Winnipeg

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Winnipeg will continue to see mild conditions with daytime highs close to the freezing mark through the weekend.

RDPS 2m Temperature Forecast valid 18Z Saturday February 11, 2023
Mild temperatures will move through southern Manitoba on Saturday with highs climbing above freezing in most areas.

A westerly flow aloft will continue to spread mild Pacific air across the Prairies this weekend. This will keep daytime highs seasonably mild in the Red River Valley and keep the storm track just to the north. As a result, Winnipeg and area will see a very pleasant weekend.

Temperatures will climb to around -2 °C in Winnipeg today with a breezy southerly wind near 30 gusting 50 km/h. Although a low pressure system is moving into Manitoba, skies will stay mainly sunny in Winnipeg as most of its cloud stays north of the RRV.

The area will see clear skies tonight as temperatures continue to rise to around +1 °C. The wind will ease overnight and shift to the west by morning.

For Saturday, the day will start off with sunshine and mild weather as temperatures climb a degree or two more. Some cloud will work into the region later in the day as a cold front slumps southwards into the Interlake. No precipitation will fall in Winnipeg, but some light snow or even a rain shower is possible further north.

Temperatures will dip to a low in the -5 to -10 °C range on Saturday night with clear skies.

Sunday will bring more warm weather to the region with a high just a bit cooler than Saturday. The region may see some cloud in the afternoon as a weak push of warmer air moves through.

Skies will clear out on Sunday night with a low again dropping into the -5 to -10 °C range.

Long Range Outlook

More warm weather is on the way for Monday with a light south wind and a high near 0 °C. Cloud will move in on Monday night as the next disturbance to affect southern Manitoba moves into the area.

Tuesday will continue to bring mild temperatures, but some flurries are likely later in the day as a cold front sweeps through the region. Some light snow will continue to be possible on Tuesday night as north winds pick up and usher in a much cooler air mass.

The flurries will taper off mid-week with highs dropping back towards seasonal values. Temperatures will likely stay near seasonal values into the weekend.

Today’s seasonal daytime high in Winnipeg is -9 °C while the seasonal overnight low is -19 °C.

Mild Weekend Ahead for Winnipeg

Brad Leave a comment

A push of Pacific warmth will bring cloudy and mild conditions to Winnipeg this weekend.

RDPS 2m Temperature Forecast valid 21Z Sunday January 15, 2023
A passing low pressure system will bring very mild temperatures to Winnipeg and the Red River Valley on Sunday.

A slow-moving low pressure system will push warmer air across the Prairies over the next few days. This warmer air will bring with it plenty of cloud cover — it definitely seems like we need to enjoy those fleeting moments of sun while we have them — as daytime highs rise towards the freezing mark.

Some morning sun today will give way to cloudier skies with a high in the -5 to -10 °C range. The cool morning temperatures in the -15 to -20 °C range will result in windy conditions this afternoon as the warmer air pushes in. Southerly winds will increase to around 40 gusting 60 km/h later this morning. Winds will ease later this afternoon, then the city will head to a low near -10 °C under cloudy skies.

Expect mainly cloudy conditions through the weekend with southeasterly winds near 20 km/h on Saturday and lighter on Sunday. Daytime highs will climb into the -5 to 0 °C range for both Saturday and Sunday as a low pressure system pushes into Saskatchewan. Overnight lows will also be quite mild near -5 °C. While the occasional few flakes are possible, any notable snow will stay north and west of Winnipeg.

The most organized area of snow will develop over Saskatchewan on Saturday evening and spread through WestMan and the northern Interlake on Saturday night. A swath of 5 to 10 cm is likely, with localized higher amounts possible as it moves into central Manitoba. The Red River Valley will stay mainly unaffected by this system.

Long Range Outlook

A few flurries will be possible on Monday as a cold front sweeps through the Red River Valley behind the passing low. Temperatures will begin to cool, with near-seasonal values returning for Tuesday. After that, though, milder air will again work its way into the region with daytime highs climbing back towards -5 °C by the end of the week.

For those missing the sun, the week ahead will continue to disappoint. Mainly cloudy conditions will persist through next week, though a few sunny breaks will be more likely on Tuesday.

While everyone’s tastes vary, the cloud cover is generally the trade-off needed for warmth at this time of year. Personally, I’ll take the trade-off of cloud for warmth as it makes getting outside and doing things so much more pleasant. But pretty soon even I’ll be willing to take the trade-off of a few -20 °C days for some blazing sunshine.

Today’s seasonal daytime high in Winnipeg is -13 °C while the seasonal overnight low is -24 °C.