Tag: light snow

The Deep Freeze Loosens Its Grip

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After suffering through the 6th coldest December on record and a January that has seen all but one night drop below –30°C, a reprieve from winter’s icy grip is on the horizon as the upper air pattern finally shifts and allows some warmer air to spill eastwards into Manitoba.

Wednesday

-23°C / ↗ -16°C
Mainly sunny. Light snow with strong winds overnight.
Thursday

-8°C / -10°C
Light snow and strong winds tapering off in the morning then cloudy.
Friday

-3°C / -9°C
Mixed skies with chance of flurries in the evening.

Wednesday

Today will be the last sub-minus 20 day we’ll see this week! Our temperature will climb from our overnight low around –32°C up to around –23°C this afternoon under mainly sunny skies. We’ll see increasing cloud late in the afternoon or through the early evening as a warm front approaches from Saskatchewan. Temperatures will continue to rise overnight as the warmer air pushes into the province; we should rise to around –15°C by tomorrow morning.

In addition to the warmer air, we’ll also likely see some light snow move in with the cloud. The light snow will start overnight and taper off through Thursday morning. Amounts will be fairly minimal; here in Winnipeg we might see as much as a whopping 1–2cm while the southern Red River Valley will likely just see a few flurries with no significant accumulation.

Models are forecasting a very strong inversion over Winnipeg on Thursday morning; the large temperature contrast will produce very strong southerly winds.
Models are forecasting a very strong inversion over Winnipeg on Thursday morning; the large temperature contrast will produce very strong southerly winds.

The other significant weather tonight will be the increasing southerly winds. As the warm front approaches from the west, very warm air aloft will push into the Red River Valley. Temperatures at 850mb are expected to rise from around –15°C on Wednesday evening to close to 0°C by Thursday morning. With dense, cold Arctic air still in the Red River Valley, this strong temperature inversion will induce stronger winds than just the pressure gradient would imply. It’s difficult to pin down, but I think that we’ll see the winds pick up through Wednesday evening to 40–50km/h by Thursday morning with gusts as high as 60–70km/h. If things are able to completely decouple or the Arctic air is miraculously expedited out of the Valley very quickly, then we might see the winds remain calmer, somewhere between 20–30km/h; I don’t think this is particularly likely, though.

Thursday & Friday

We’ll see light snow slowly taper off on Thursday morning and then mainly cloudy skies thereafter. The winds will taper off through the morning to around 15–20km/h and remain there for the remainder of the day. Skies will remain mainly cloudy and we’ll see our temperature climb to a comparatively balmy (and warmer than normal) –8°C. Clouds will scatter out a bit on Thursday evening leaving us with partly cloudy skies and a low near –10°C.

More warm air pushes into the region on Friday as a low pressure system tracking through Central Manitoba drags another shot of warm air eastwards. Our temperature should climb to around –4 or –3°C under increasingly cloudy skies. Winds will be fairly light as well which will make it quite a pleasant day. Some light flurry activity is possible Friday evening and overnight into Saturday as we drop to a low near –10°C once again.

The Weekend

More warm weather is ahead for the weekend with daytime highs near –5°C on Saturday and possibly breaking 0°C on Sunday as a low pressure system winds up over the region, bringing potentially an inch or two of snow and a slight risk of some freezing rain. Mild temperatures continue into next week, so enjoy a nice break from the cold!

Milder Weather On Tap

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A broad trough of low pressure will push eastwards across the Prairies bringing with it milder temperatures and the occasional chance for some more light snow.

Friday

-7°C / -14°C
Mainly cloudy with flurries.
Saturday

-8°C / -12°C
Mixed skies; slight chance of isolated flurries.
Sunday

-8°C / -10°C
Cloudy with a chance of scattered flurries.

We’ll see fairly cloudy skies today alongside an increasingly brisk southerly wind to 30–40km/h as a warm front approaches the Red River Valley from the west. This front will produce an area of 5–10cm of snow through the Interlake and areas west and north, but here in the Red River Valley we’ll see some periods of light snow with no significant accumulations expected. Temperatures will climb to around –7°C as the winds ease up in the afternoon and see gradual clearing through the evening and overnight as the mercury then drops to about –14°C.

Saturday will bring a few remnant clouds in the Red River Valley that will possibly produce some isolated flurries, but it should end up being a mostly sunny day with light winds and a high near –8°C.

Cloud will roll in on Saturday night as a low-pressure system begins working it’s way across North Dakota. The accumulating snow is expected to remain States-side at this point, with just some light snow working it’s way north of the border. Minimal accumulations are expected at this point, although regions close to the U.S. border could possibly see a cm or two of the white stuff if the system tracks just a smidgen further north.

The Start of Next Week

The first half of next week looks to bring some very mild air into Southern Manitoba with temperatures climbing as high as low minus-single-digits on Monday! It will be short-lived, however, as a significant cold trough begins working it’s way into the Prairies and brings below-normal temperatures for the second half of the week.

Improving Weather

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Southern Manitoba will see improving conditions today and round out the work week with nice conditions and near-normal temperatures.

Ridge Dominating Southern Manitoba

Model 3hr. QPF & MSLP w/Surface analysis valid 00Z Thursday April 19th

There will be a slight chance of some light snow this morning over the western half of the Red River Valley as a weak short wave slumps into North Dakota. As it exits the province, clouds will clear and we’ll be left with a sunny afternoon with a high near 8°C.

Clear skies will be the weather story for the rest of the week as a ridge of high pressure builds in from Northern Saskatchewan. We’ll have an overnight low near -6°C tonight and warm back up to a repeat of today on Thursday, with a high near 7°C. Rinse and repeat for Thursday night. As a system pushes into the NW United States, slightly warmer air pushes into Southern Manitoba and we’ll likely see our daytime high bumped up a few degrees to around 10°C.

Saturday brings with it a chance of rain as an upper trough swings across the Prairies. We’ll keep an eye on that as the week progresses!

In short, it’ll be a sunny, albeit a little cool, rest of the week!

Major Arctic Outbreak Next Week…But First, Milder Weather

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Our shot of winter this week won’t look so bad by this time next week! Slightly warmer temperatures today will be followed by some light snow tonight and a dreary but milder weekend, before the coldest airmass we’ve seen this winter settles in over much of the Prairies.

Today will bring warmer temperatures as Pacific air pushes east-southeast across the Prairies. Temperatures should be able to make it up a little past the -15°C mark by early to mid-afternoon. Clouds will roll in by evening, and we should see some light snow in the evening and overnight with temperatures staying fairly steady overnight as warmer air continues to push into Southern Manitoba. Winnipeg will likely see 2-4cm of snow as relatively high snow to liquid water ratios (SLR) are expected, around 15:1 to 20:1.

Snow to Liquid Water Ratio (SLR) is a measure of how much snow is produced per millimetre of water. For example, a SLR of 20:1 would mean that for each 1mm of liquid water that fell, there would be 20mm, or 2cm. If someone received 10cm of snow, and that was melted and resulted in 4mm of water, then the SLR would be 25:1. The higher the SLR is, the ‘fluffier’ the snow.

Milder temperatures will be seen in the southwest and south-central portions of Manitoba on Saturday and Sunday. Temperatures will reach between -10°C and -5°C in the Red River Valley this weekend, with relatively light winds and plenty of cloud.

Surface Temperatures, Saturday Afternoon

Surface temperatures valid 12Z Saturday Morning (6AM)

We could see some light snow on both days as well, but significant accumulations (2+ cm) are unlikely. The days may be a little dreary, but enjoy the warmer temperatures while you can. Next week will be shockingly different.

Cold Front Passing Through Monday Morning

Surface analysis of forecasted temperature field valid 06Z Monday, Jan. 16. Warm front is represented by red line and cold front is represented by the blue line.

Early Monday morning, a cold front will sweep through Southern Manitoba, ushering in a completely different weather regime. We’ll see steady or dropping temperatures through the day Monday with some accumulating light snow through much of the RRV, especially north of Morris. Current indications show that 2-4cm looks reasonable, with 5-10cm possible for areas north of Winnipeg. Snowfall amounts in the City of Winnipeg will be sensitive to the exact track of the low, so we’ll keep an eye on that system as it develops.

The entire change will be driven by a long wave trough rotating southeast from Alaska into the Central Prairies. This will drive the jet stream south into the Northern U.S., allowing bitterly cold Arctic air to spill southwards into the Prairies. Just how cold is it going to get?

Bitterly Cold Temperatures Monday Night

Surface temperature prog valid early Tuesday morning, 12Z (6AM) January 17. Many areas in Southern Mantioba will see temperatures in the low -20’s with some spots in the southwest corner potentially reaching as cold as -32°C or -33°C. A wide swath of temperatures dipping below -40°C is forecast through Central Saskatchewan.

The coldest air we’ve seen all winter at 500mb will be pushing into the Prairies, with temperatures at that height forecast to be between -40°C and -45°C over most of the Prairies. What does this mean for temperatures at the surface? The GEM-GLB model is currently forecasting a swath through East-Central Alberta and Central Saskatchewan that will experience overnight lows between -40°C and -45°C!

For the third week of January, average daytime highs are around -13°C and average overnight lows are around -23°C. We will be several degrees below normal for a couple days next week.

This cold air will slump southeastwards bringing bitterly cold temperatures into Southern Manitoba, with overnight lows near -30°C and daytime highs struggling to climb above -20°C. By mid-week, temperatures may moderate into the mid-minus-teens as some cloud cover spills into the Southern Prairies associated with a system tracking through the Northern Plains. It may feel extremely cold, however, as we may be dealing with stiff northeast winds as the system moves through the area.

The cold air looks to be entrenched for the whole week, but we’ll have more on that on Monday. Get out and enjoy the weekend as best you can! It’s hot drinks and oatmeal weather next week!