Tag: Snow

Seasonal Weather Continues Through Weekend

Brad Leave a comment

Our streak of surprisingly seasonal weather will continue through the weekend as another push of Pacific air sweeps across the Southern Prairies.

850mb Temperatures Saturday Morning

850mb temperatures valid on Saturday morning. A warm front will be pushing across Southern Manitoba ushering in mild Pacific air and a very slight chance of a dusting of snow.
Friday

Mainly sunny.
-7°C / -14°C

We’ll see a mainly sunny day today as spend a final day under the effects of a weak ridge. Temperatures will climb to around –7°C, although depending where you are in Winnipeg, temperatures could climb locally to –5 or –4°C as more and more concrete is exposed.[1] Temperatures will dip down tonight to around –15°C before clouds begin to move in ahead of the approaching warm front.

Saturday and Sunday

Saturday

Mainly cloudy.
-3°C / -7°C
Saturday

Mainly cloudy.
-2°C / -7°C

Milder Pacific air will push into the Red River Valley this weekend warming temperatures up close to the 0°C mark. Both Saturday and Sunday will be mainly cloudy and other than a very slight chance on Saturday morning of a light dusting, no snow is expected. Temperatures will only drop to around –7 or –8°C both Saturday and Sunday night.

Next Week

Models seem to indicate a system diving southwards into North Dakota but differ on what to expect from it. Current indications are that no significant snowfall will be seen over Southern Manitoba, although the GEM-GLB is painting a swath of 20+cm through our region. We’ll keep a close eye on it as the weekend progresses. Even with the passage of this system, temperatures aren’t expected to drop more than a few degrees and we should continue to see daytime highs warmer than –10°C through the week.

  1. Concrete has a lower albedo than snow-covered ground. Albedo is a measure of reflectivity of a surface; because concrete’s albedo is lower, it reflects less sunlight and warms up more. This effect is very noticeable at this time of year over forested areas where temperatures can climb as much as 10°C higher than open, snow-covered areas adjacent to them.  ↩

Elsewhere in Weather News: February 23rd, 2013

Matthieu Leave a comment

Major Snowstorm Hits US Plains

Another trough digging through the southern half of the US this past week, caused trouble for travellers and residents of the Great Plains. Moist air from the Gulf of Mexico made its way north into Kansas which fell as freezing rain and snow ahead of the warm front. In the warm sector a line of thunderstorms, some severe, formed along the trough line that plowed through part of Texas and Louisiana.

850mb analysis

850mb analysis of early Wednesday morning. Heavy snow was already falling at this time. Highest accumulations circled in pink. (Source: Twisterdata)

Highway conditions quickly deteriorated after snow started falling and 150km of I-70 had to be shut down in Kansas due to many vehicle accidents. This system also prompted the closure of schools, delayed flights at airports or even closed airports such as the Kansas City airport. This same trough is to be blamed for suspending play at the PGA in Marana, Arizona where an uncommon sight could be seen; snow – about 4cm of it, covered luscious greens with cacti nearby in the background.

Snow affecting PGA

PGA golfers leaving the course while it’s snowing. (Source: AP)

Snowfall rates of 3-5cm/h were not uncommon for several hours in Kansas and Nebraska and contributed to significant snow accumulations. Highest accumulations were just below the two foot mark (60cm) in south-central Kansas with a good part of Kansas receiving over 20cm of snowfall. Most of the Southern Plains residents welcome any type of precipitation at this time however due to a severe/extreme drought is currently in place through much of the Plains (as talked about in last week’s EIWN). Last Thursday’s storm should at least make for slight improvements in the short term drought index but for longer range improvements the Plains need to get out of a persisting dry pattern.

Recent model runs show another major snowstorm, with as much as another foot of snow, Sunday night into Monday for the US Plains.

Warming Up This Weekend; Snow for Sunday

Brad Leave a comment

Another low pressure system developing over the Yukon Territory will push milder air into Manitoba tomorrow and return us to normal-becoming-above-normal temperatures by the end of the weekend. This low pressure system will slide southwards through the province on Sunday, bringing some light snow with it.

4AM Satellite Composite

North American composite satellite image showing the surge of warmer air pushing into the Alberta. Image valid for 4AM CST.
Today

Mostly cloudy with periods of light snow.
-13°C / -18°C

The Red River Valley will be mainly cloudy today as a mass of stratus pushes down from Central Manitoba, sliding southwards into North Dakota, bringing periods of light snow throughout the Red River Valley. Temperatures will climb to around –13°C this afternoon and temperatures will drop to around –18°C tonight as skies clear this evening.

Saturday

Saturday

Mix of sun and cloud. Patchy flurries in the afternoon.
-6°C / -8°C

The warm front will push across the Red River Valley through Saturday afternoon, pushing our daytime highs up to an above-seasonal –6°C. Skies will become a mix of sun and cloud as the warm front moves in which, when combined with 850mb temperatures sitting near –10°C, will produce some scattered flurries across the Red River Valley. Skies will completely cloud over on Saturday night with temperatures falling to and remaining steady near –8°C.

Sunday

Sunday

Light snow beginning in the afternoon. 2-4*cm*.
-3°C / -7°C

Sunday will be the most active day of the bunch as this low pressure system finally pushes through. Temperatures will climb up to around –3°C as light snow pushes in midday. This system will not be particularly intense; total snowfall accumulations for the afternoon look to be only a couple cm. The light snow will persist through much of the night with another cm or two falling by morning as temperatures dip to about –10°C. Overall it looks like the Red River Valley will see less than 5cm of snow total with this system.

Some disagreement does exist within the models, in particular pertaining to the intensity of this system; the Canadian GDPS is, in particular, quite gung-ho on making this quite a potent system. It’s hard to tell what to make of it, considering it’s the outlier when compared to the other major models and this is the first significant weather system since CMC upgraded the GDPS on Wednesday claiming an improvement to the output “usually seen only once a decade.” Should the GDPS solution be the correct one, the forecast for Sunday should still hold up, save for the potential for a little more snow (closer to 4–6cm instead of 2–4cm). Monday, on the other hand, would likely be a significant winter storm with close to 10cm of snow falling and blizzard conditions through the Red River Valley (excluding the City of Winnipeg). The other models have just a couple cm of snow for Monday with breezy northwesterly winds, but nothing that would produce more than some local blowing snow. Right now, I think that the GDPS is digging the low out of SK too much and has it pushing too far south which would intensify the low too much and end up producing too much snow & wind. It looks more reasonable for a couple cm of snow and some breezy north winds producing just some local blowing snow.

So we’ll have an increasingly warm and mainly pleasant weekend ahead; Monday looks to be a wild card at this point, but holds the potential to be a significant winter storm event. We’ll post updated information as we get closer to the event in the comments below. Enjoy the long weekend!

Alberta Clipper To Blast SW Manitoba

Brad Leave a comment

A powerful Alberta Clipper system will push through southwest Manitoba this evening bringing heavy snowfall and blowing snow to the region.

Probability of > 2cm of snow from this AB Clipper

Probability of > 2cm of snow from this AB clipper. Blue boundary marks > 30% chance, green boundary marks > 60% chance.

The weather across Southern Manitoba will be fairly benign today with daytime highs generally sitting just below the freezing mark with increasing clouds through the day. Winds will remain light through the day. Light snow will push into southwestern Manitoba this afternoon, potentially pushing into the western Red River Valley as well. Winnipeg may see some light snow this afternoon, but it’s going to likely remain to our southwest; should snow push into the city, there will be little-to-no accumulation. Regions that see more persistent snow today, potentially including the western Red River Valley, accumulations will likely total around 2-ish cm.

Wednesday

Mostly cloudy with patchy light snow.
-3°C / -16°C

Early this evening the Alberta Clipper will begin working it’s way into the Virden & Melita regions, quickly expanding eastwards towards Brandon and Pilot Mound. General snowfall accumulations will be close to 5cm, but there will also be a very narrow band, just north of the track of the clipper, where accumulations will be closer to 10cm. This corridor of heavy snow will lie across the Trans-Canada highway near the Saskatchewan border; anybody travelling west tonight should prepare to encounter heavy snow, snow drifts and near-zero visibilities near the Saskatchewan border. Further east, there’s a little disagreement on what will happen; most models suggest very little snow will fall in the Red River Vally tonight, however the NAM guidance is suggesting that a fair amount could fall. At this point, I think that most of the snow will push into North Dakota before it pushes eastwards towards Winnipeg or the central Red River Valley. Areas near the International Border may get clipped with a couple cm of snow as this clipper exits the region. Winds will remain relatively light, picking up to 20 gusting 40km/h out of the northeast overnight through much of Southern Manitoba. Temperatures will drop to around –14 to –16°C across Southern Manitoba.

Thursday

Thursday

Clearing in the morning.
-14°C / -21°C

Cooler air will filter into Southern Manitoba on Thursday behind the clipper, bringing us a return to seasonal temperatures. The remaining cloud from Wednesday’s system should clear out fairly early in the day, leaving us with mainly sunny skies. We’ll climb to around –13°C with a light north wind. Temperatures will drop into the –20’s tonight as another Arctic ridge slumps into the Prairies.

Friday

Friday

Clearing in the morning.
-14°C / -20°C

Southern Manitoba will be locked under the Arctic ridge on Friday which will result in another day with seasonal temperatures. Highs will sit near –15°C on Friday across most of Southern Manitoba with temperatures dropping back towards –20°C for the night.

After that, it looks like we’ll head back towards above-normal temperatures for a few days. Little-to-no precipitation is expected over the next while.