More Snow on the Way

sigh

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850mb wind forecast showing the deep southerly flow that will be providing the moisture and lift for today’s system.

Today

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0°C / -2°C
Snow beginning this afternoon. 2-4cm overnight.

A frontal wave sliding across the Prairies will push into Southern Manitoba this morning, spreading snow eastwards across the Red River Valley this afternoon. While southwestern Manitoba will see 5–10cm of the white stuff, we should fare a little better here in the RRV with 5cm expected near the US border tapering off to 2–4cm here in Winnipeg. The bulk of the snow will fall this evening into the overnight period before tapering off late overnight or early tomorrow morning.

Saturday & Sunday

Saturday
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1°C / -11°C
Cloudy with a chance of flurries. Clearing late in the day.
Sunday
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-4°C / -14°C
Increasing cloud. Light snow beginning in the afternoon.

Saturday will be a bit of a mixed bag with some lingering flurries in the morning and gradual clearing in the afternoon before skies clear late in the afternoon or evening. The high temperature on Saturday should be around 1°C and we’ll see temperatures drop to –11 or –12°C Saturday night.

More snow looks to be on the way for Sunday afternoon as an Alberta Clipper slides along the international border. At this point, it doesn’t look like a significant system, but it should pack enough of a punch that it will likely drop a couple cm through the RRV in the afternoon. After Sunday, it looks like we’ll slip back into another benign pattern with below-normal temperatures as a surface ridge keeps snowier weather to our west and to our south.

Warmest Day of Spring So Far Will Also Be Most Unpleasant

It’s almost a certainty that Winnipeg will record the warmest day so far this spring at it’s official reporting station at the airport, but it will without question be perhaps one of the most unpleasant feeling days of the past couple weeks as a low pressure system moves through.

3hr. QPF valid this afternoon.

RDPS output showing a weak band of flurries pushing across the RRV this afternoon.

Today


3°C / -9°C
Cloudy & windy. Chance of flurries midday onwards.

A low pressure system will be tracking through Southern Manitoba today, bringing with it a mass of very warm air. Temperatures at the surface will climb to around +3°C today despite our 850mb temperatures climbing nearly 20°C from yesterday’s values. Thanks to the significant push of warm air aloft moving into the Red River Valley, our winds will be blowing quite strong today out of the south. The winds should sit around 40km/h with gusts to 60km/h through much of the morning, although it’s possible that winds will strengthen beyond that with gusts as high as 70–75km/h.

In addition to the above-zero temperatures, our dewpoint is expected to climb above zero as well. The above-zero temperatures combined with above-zero dewpoints will prove to be one of the more effective melting days we’ve seen so far this year despite the absence of sun with substantial warming of the entire snowpack possible. We may see some flurries as the cold front pushes through in the afternoon, but current indications are that the air coming in is a little to dry to produce much precipitation. Before the cold front comes through, the thermodynamic profile looks relatively favourable for drizzle, but I think that the strong winds will prevent its development. All in all, despite the warmer temperatures, today will end up a cloudy, damp, windy chilly-feeling day.

Once the cold front pushes through mid-afternoon, we’ll see winds lighten and slowly shift to westerlies while gradual clearing occurs. Temperatures will drop to around –9°C tonight under clear skies.

Thursday & Friday

Thursday

-2°C / -14°C
Mainly sunny.
Friday

0°C / -8°C
Mainly sunny. Increasing cloud overnight with chance of flurries.

We’ll return to a benign pattern for the rest of the week as another Arctic ridge builds into the Prairies. We’ll see plenty of sunny skies and highs near or just under 0°C while overnight lows sit around –14°C on Thursday night and warm to just –8°C on Friday night as clouds begin to move in ahead of the next low pressure system. Winds will remain light through Thursday and Friday.

The Weekend

Models are having difficulty resolving exactly what is going to happen with the next system headed our way for late overnight Friday into Saturday. American models are keeping it well to our south, the Canadian models are clipping it through SW Manitoba and the far SW portions of the Red River Valley, while the European models are bringing it through the Trans-Canada corridor, including Winnipeg. While the European models tend to have higher skill than the North American models at long-range (primarily thanks to their relentless efforts to initialize the models as well as they possibly can), the solution doesn’t necessarily make a whole lot of sense to me.

We’ll be watching this system develop over the next few days, and while it seems likely that some snow will fall this weekend over SW Manitoba, it’s still too early to call for Winnipeg or the RRV; we may see nothing or another 5–10cm of the white stuff. At this point, regardless of where it goes, it doesn’t look like a major system that will drop too much water (ensemble solutions are pointing towards 5–10mm of liquid equivalent with this system).

Long-Range

This cool weather of late has many people asking when spring will arrive. Our snowpack is abnormally deep for this time of year, March started off warm but just got colder and colder as time went on, and we have yet to even start the widespread snowpack melt. All this is certainly compounded by memories of last March’s weather, where we had the warmest March on record at 2.2°C, 0.6°C above the previous record.[1] Fortunately, there is some hope on the horizon.

AO Graph

AO values over the past few months. A quick flip from negative to positive values is expected, denoted by the forecast red line.

The Arctic Oscillation (AO), a large-scale weather pattern that can impact the distribution of cold air through the Northern Hemisphere, has been locked below zero for quite some time now. When the AO value is negative, it usually results in a stationary pool of cold air over central continental North America, as we’ve seen over the past few weeks. This has brought below-normal temperatures to many locations across the Prairies and northern United States. The good news is that, as seen above, the AO values are expected to sharply shift into the positive over the next two weeks, which should allow the jet stream to start pushing northwards and bring warmer weather to our region. So while the cooler weather will likely be here for the next 7–10 days at least, a significant change in the weather pattern looks like it’s on it’s way in the near future.


  1. Check out the mentioned link for a list of the 9 significant records we broke in March 2012.  ↩

Major Warm-Up To Start April

It look like a major warm-up will usher in the month of April. These warmer conditions come after an abnormally cold March.

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High pressure will dominate at the surface on Monday (College of Dupage image)

…April fools! No major warm-up is in the cards this week, so read on to see what you can actually expect.

Monday

Monday
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Mix of sun and cloud. Chance of flurries.
-6°C / -12°C

Monday will be a very similar day to Sunday. The lower atmosphere will once again be quite unstable, so flurries will be possible throughout Southern Manitoba. These flurries will be fairly localized in nature and will not affect everyone. Those areas not under the influence of these flurries will see a mainly sunny day, while other areas will see a combination of clouds and flurries as well as periods of sunnier skies. Generally speaking, high temperatures will be in the mid to upper minus single digits, making it a seasonably cold start to April.

Tuesday and Wednesday

Tuesday
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Mainly Sunny
-4°C / -8°C
Wednesday
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Mix of sun and cloud. Chance of flurries.
2°C / -10°C

Tuesday will be slightly warmer than Monday, but not by much. Highs will be in the mid single digits in most areas. The wind will be calm and the sky sunny, so the cities and forested areas will once again be slightly warmer than everyone else.

We will finally warm up to the melting point again on Wednesday, but it won’t be a major warm-up. All of Southern Manitoba should see high temperatures in the low to mid positive single digits.

Long Range

In the longer range models are struggling to resolve the pattern. It appears fairly certain that a cold front will come through on Wednesday night, making Thursday a cooler day once again. However, beyond that things are quite unclear. Some model runs have been showing consistently warmer weather into next weekend, while others have shown cold weather persisting. We’ll just have to wait and see what happens…

A Cooler End to the Weekend

We’ll see two more days of temperatures near or just above 0°C before a cold front sweeps through Southern Manitoba bringing minimal precipitation and cooler weather.

12hr. QPF valid Sunday morning

Precipitation amounts for Saturday night from the NAM forecast model.

Today and Tomorrow

We’ll be off to a cloudy morning with fog patches through the entire Red River Valley; the fog may be quite dense in some areas, so if you’re travelling be prepared to potentially face near-zero visibilities at times. The fog will lift through the morning and by mid-afternoon the sun should be poking out once and a while. We’ll be on our way to a high of around +1°C with light winds. We’ll see increasing cloudiness tonight as the aforementioned system pushes towards Southern Manitoba. The cloud cover will help us keep our overnight low a bit higher than it has been lately with the temperature only expected to dip down to about -5°C. It’s likely that well see the redevelopment of fog patches again tonight.

Friday

Fog patches lifting this morning with gradual clearing.
1°C / -5°C
Saturday

Fog patches lifting then a mix of sun and cloud.
3°C
Saturday Night

A few flurries with the risk of freezing rain.
-12°C

We’ll see temperatures slowly climb back up above 0°C today as the cold front approaches the Red River Valley. Any fog patches that form overnight will lift fairly quickly in the morning as we head into another nice day with a mix of sun and cloud as the temperature climbs to +2 or +3°C.

A cold front will sweep across the Red River Valley tonight, bringing some flurries with it. There’s some uncertainty to the distribution of the snow: the models tend to spread it out, but all simultaneously hint towards a narrow band of heavier precipitation setting up. It’s hard to tell what’s going to happen this early, but suffice to say that there will almost certainly be a few flurries with the potential for local accumulations of 2-4cm somewhere in the RRV. In addition to the snow, there will be the potential for some patchy freezing rain as there will likely be some precipitation before all our warmer air aloft is scoured out by the cold front. Accumulations of freezing rain should not be significant, but may be enough to slick up roadways a little.

Sunday

Saturday

Chance of flurries. Clearing.
-6°C / -15°C

There will be a few lingering flurries about on Sunday morning, but they should clear out by midday and skies will then clear out. Sitting on the back-side of the cold front, our temperature will only climb to around -6°C, although it might be a little colder than that if clouds linger further into the day.

It looks like the cold weather will only stick around for a couple days until temperatures rebound back to the 0°C mark.