Category: Forecasts

Unsettled End to the Week

Brad Leave a comment

Temperatures will slowly return to slightly below-seasonal values through the remainder of the week as unsettled weather pushes into the Red River Valley. While the main weather focus will remain further east as a significant low pressure system lifts through Central Ontario, the storm will have a broad reach spanning all the way from the Maritimes to Southern Manitoba.

This forecast precipitation panel from the GDPS shows the significant extent of this week's develping storm.
This forecast precipitation panel from the GDPS shows the significant extent of this week’s develping storm.

One More Mild Day

Wednesday
-4°C / -9°C
Increasing cloud; mild. Snow overnight.

Today will bring another fairly nice day a westerly flow aloft continues spreading warm air into Southern Manitoba. Temperatures should climb up to around -4°C with relatively light southeasterly winds. Cloud coverage will increase through the day as a trough of low pressure works it’s way towards the Red River Valley, bringing with it another batch of snow and the beginning of of our transition back towards seasonal to slightly below-seasonal temperatures.

As the cloud pushes in, so too will the snow. Initially, the snow will spread into the Parkland region of the province – through Dauphin and down towards Minnedosa – before pushing eastwards into the Interlake. As the system tracks east, it will do it’s best to develop some light snow over the Red River Valley as a low-level jet ramps up and lifts over the warm front stationed in North Dakota. It’s still too early to say exactly how this is going to shape out: the location and intensity of the precipitation will have a lot to do with the exact track & timing of the system. If things line up right, we may see a band of moderate snow track across the RRV fairly early in the evening, but just as likely is that the LLJ doesn’t really get precipitation going until it’s further east into Minnesota, which could drastically reduce snowfall expectations depending on how much of that is able to wrap all the way around the low back into the Red River Valley.

Snowy Thursday

Thursday
⇒ -9°C / -15°C
Periods of light snow; 3-6cm accumulation.

Thursday looks to bring more snow Southern Manitoba as Wednesday’s system is absorbed into a much larger storm lifting northwards through Central Ontario. As a notable aside, this storm is absolutely massive, stretching from Manitoba all the way to the Maritimes and from Quebec all the way southwards to Florida.

The inherent uncertainty of both track and timing makes snowfall totals quite difficult. The highest confidence is for snow through the Parkland into the Southern Interlake and east. A combination of strong lift and a decent deformation zone look to produce a band of snow with totals from around 5-10cm. Assuming the currently forecast track of the system, we would then see around 3-6cm of snow through the northern Red River Valley – including Winnipeg – and 1-3cm or less through the southern Red River Valley.

Temperatures will be cooler on Thursday as a northwesterly wind keeps temperatures steady near -9°C. Temperatures will dip to around -15°C tomorrow night under mainly cloudy skies with a chance of a few flurries.

Cool Weekend Ahead

Friday
-13°C / -20°C
Mixed sky; chance of flurries.

Friday continues the cool trend with temperatures only recovering a degree or two – to around -13°C – while moderate northwesterly winds continue to make things unpleasant. There will be a slight chance of flurries through the day under mixed skies, but things should clear out on Friday night as we head to a low near -20°C.

The weekend will bring more cool temperatures as daytime highs slump towards -17 or 18°C under sunny skies by Sunday and overnight lows dropping below -20°C in the overnight periods.

Warm Weather!

Brad Leave a comment

This week will feature some of the warmest weather we’ve seen in a long time – it’s about time!

A warming trend will occur across southern Manitoba on Monday

A warming trend will occur across southern Manitoba on Monday

Early Week

Monday
-2°C / -10°C
Mainly Sunny
Tuesday
0°C / -14°C
Mainly Sunny
Wednesday
-1°C / -7°C
Increasing Cloudiness. Chance of Flurries Late.

Today will see temperatures climb up towards the freezing mark in southern Manitoba. That will make for messy roads, but that’s the price you have to pay for warmer weather. The wind will be light and from the west to south-east, making for a great day.

Tuesday will be very similar to Monday, with temperatures once again near zero. There will be a breezy west wind, but otherwise it will be a very nice day.

Wednesday looks to remain seasonably warm, with high temperatures once again, you guessed it, near zero. However, a low pressure system will move towards the region on Wednesday, bringing increasing clouds and a chance for flurries by late in the day. Thankfully, major snow accumulations are not currently expected with this system.

Long Range

That low pressure system from Wednesday will pull down another cold airmass for the late week period. As a result, long-range models suggest we’ll see a colder pattern lasting at least through next weekend.

The Big Warm-Up Inches Closer

Brad Leave a comment

Southern Manitoba will finally see a reprieve from the icy grip of winter as a major pattern change will allow Pacific air to wash over the Prairies bringing substantially warmer – and more unsettled – weather.

Friday
-17°C / -20°C
Mainly cloudy. Chance of flurries this evening & overnight.

Saturday
-14°C / -23°C
Mainly cloudy; chance of morning flurries.

Sunday
-9°C / ⇒ -9°C
Strong winds with blowing snow. Chance of snow late day.

A Couple Cool Days

There will be a chance to dig out after Wednesday night’s storm dumped around 10-15cm through most areas in Southern Manitoba as cool, fairly benign weather settles in over the Red River Valley for the next couple days. Mainly cloudy skies will persist through much of the day today as we climb to a high of only around -17°C.

As shown by the RDPS imagery above, flurries are possible tonight (light blue) over much of Southern Manitoba.
As shown by the RDPS imagery above, flurries are possible tonight (light blue) over much of Southern Manitoba.

A weak disturbance will push through tonight that will push some light snow through the Interlake, but further south in Winnipeg & the Red River Valley there will be just a chance for some flurry activity. The relative weakness of the disturbance combined with quite cool temperatures will ensure that if anything manages to develop it will be quite light and not really accumulate to much at all. We’ll remain cloudy through the night and drop to a low around -20°C.

Saturday will be a fairly quiet day with any possible flurry activity tapering off in the morning and then seeing clouds slowly try to break up through the day. Some clearing should work it’s way in later in the day, but it’s a little uncertain how clear we’ll get. While it will have little bearing on any significant weather, it will dramatically affect our overnight low. If we remain a little cloudier – which I’m thinking is the more likely outcome – we’ll see an overnight low of around -23 or -24°C. If the clouds manage to clear out, even for a couple hours, we’ll get quite a bit colder than that and possibly see another low dipping below -30°C. That marks the last day of cold, though, as a major pattern change begins on Sunday.

Wind and Blowing Snow Usher in Warmer Weather

Sunday will mark the beginning of a major pattern shift that will see the persistent trough that’s been anchored over Northwestern Ontario break down and push off to the east, allowing our upper-level northwesterly flow to be replaced by westerly flow. That sounds like a small shift, but the impact will be dramatic.

Sunday will see increasing cloud through the day as milder air finally pushes in from the west. By evening our temperature will rise to around -10°C and snow will be pushing into Southwestern Manitoba. There will likely be at least some flurry activity, if not some light snow on Sunday night as a warm front pushes across the Red River Valley, but accumulations – at this point – look minimal.

The forecast sounding for Winnipeg on Sunday evening shows very strong low-level winds.
The forecast sounding for Winnipeg on Sunday evening shows very strong low-level winds.

Perhaps the biggest weather impact on Sunday will be the southerly winds that will develop through the Red River Valley ahead of the warm front. A tight pressure gradient will result in strong winds developing fairly early in the day. We’ll likely see winds climb to around 50km/h sustained which will undoubtedly produce localized white-out/blizzard conditions in the Red River Valley. It’s too early to say exactly how bad it’s going to be, but it seems fairly certain that blowing snow is going to be a big issue for anyone planning to travel on Sunday, especially in the evening hours when the strong winds may combine with falling snow.

After we make it through the cold weather’s last stand, a significantly warmer – and more unsettled – week is ahead of us as the westerly flow aloft establishes itself over the Prairies. Daytime highs next week look to sit around -4°C, plus or minus a few degrees, but with the warmer weather will come multiple chances for snow as a train of disturbances set up and track across the Prairies. At this point, however, I’ll gladly take more snow if it means a break from the relentless cold we’ve seen in Winnipeg this winter.

More Snow Tonight

Brad Leave a comment

More snow is on the way for Winnipeg and the Red River Valley as a fairly strong low pressure system tracks through North Dakota and spreads snow through much of Southern Manitoba. The upside to the snow is that rather than plummeting into another deep freeze, this system will actually mark the start of a notable warming trend for Southern Manitoba!

Wednesday
-17°C / -19°C
Increasing cloud; snow beginning early in the evening. 10-15cm overnight.

Thursday
-16°C / -23°C
Occasional sunny breaks with a chance of flurries.

Friday
-18°C / -21°C
Mainly sunny.

Significant Snowfall Tonight

While today may bring mainly sunny skies through much of the day, a low pressure system set to bring a fair amount of snow is on it’s way. Temperatures will warm up to around -19°C before cloud starts streaming in from the west later in the afternoon. There’s a decent chance we’ll see some light snow through the evening, but the main shot of snow will arrive through the overnight period.

Forecast storm-total snowfall amounts by Thursday morning.
Forecast storm-total snowfall amounts by Thursday morning. Updated image; original forecast is here.

Conditions will deteriorate from west to east through the evening as heavier snow pushes into the province. In general, between 5-10cm of snow can be expected for all areas along and south of a line running approximately from Dauphin to Gimli to Pinawa, however there are two primary areas of concern I have for higher amounts:

  1. Patchy areas of very heavy snow. Several models are indicating extremely strong lift associated with this system. While the moisture supply isn’t astonishing, there’s certainly enough for me to be concerned about some embedded areas of very heavy snowfall. It’s impossible to say where these might occur at this time, but be aware that there is the potential for snow to rapidly accumulate should some of these heavier bursts of snow develop. Of course, the heavy snow would also produce near-zero visibilities, so if you need to drive overnight, be prepared for poor conditions.
  2. Higher amounts near the western escarpment of the Red River Valley. With the low pressure centre tracking far to our south, we’ll primarily see easterly and north-easterly winds through much of the event. These are favourable directions for upslope enhancement along the western escarpment of the RRV. This is a more predictable feature, and I feel comfortable saying that areas near the escarpment will see closer to 10cm, perhaps as much as 15cm if the winds align just right. The winds will shift to northerly very early on Thursday morning, so the threat will have limited time to work.

Here in Winnipeg we’ll most likely see around 10-12cm by the time all is said and done, assuming the track of the low doesn’t dramatically shift southwards. Although winds may get a little gusty this afternoon, it should be relatively light through the snowfall event itself at only around 20-30km/h. Snow will taper overnight in southwestern Manitoba and early tomorrow morning here in the Red River Valley.

A Couple Cool Days as Pattern Shifts

Thursday will bring mainly cloudy skies, although we’ll see a few sunny breaks through the day. There will be a good chance of some light flurries through much of the day and into the evening. No real accumulations should come of them, though. We’ll see a high near -16°C thanks to all the cloud followed by a low near -23°C with clearing skies overnight.

Friday will be mainly sunny and cool with a high of only around -18°C. We’ll drop down to a low near -21°C on Friday night with a few clouds pushing in.

Weekend Marks Beginning of Warm-Up

This weekend will bring warmer temperatures as a westerly flow develops aloft and brings milder Pacific air into the region. Saturday looks to bring mixed skies as an Alberta Clipper scoots through extreme SW Manitoba and North Dakota. It looks like our temperature will climb to around -13°C or so. Sunday looks to be mainly cloudy as Pacific air continues to wash over the Prairies. Models are hinting at a storm system that might bring us another batch of snow on Sunday night, but we’ll leave that one until we’re closer to the event.

Temperatures look to climb above -10°C on Sunday and close to -5°C on Monday. Better yet, it looks like the warm-up may actually be here to stay for a while!