Hot And Hazy Start to the Weekend, Cool End

An approaching low pressure system will bring hot and hazy weather to Winnipeg before a cold front passing Saturday brings a risk of thunderstorms and ushers cooler conditions back into the region.

Winnipeg will continue to see hazy skies today as the over 500 fires that have led to a state of emergency in British Columbia continue to send plumes of some eastwards into the Prairies. The thickest smoke has left the region and winds aloft should keep the main smoke track further north across the central and northern Prairies. Plenty of haze and stagnant high-level smoke will remain in the area with some limited visibility restrictions.1 The significant thinning of the smoke will let the sun shine much more strongly and send daytime highs in the region up into the low 30s. Winds will be out of the south at just 10 to 15 km/h.

Winds will increase out of the south to around 20 km/h tonight as temperatures dip to a low near 15°C under mixed skies.

Saturday should be a scorcher of a day…assuming the smoke can stay away. If we see the sun, then temperatures will soar to a high near 33°C with winds out of the south-southwest at 30 gusting to 50 km/h. Winnipeg will see partly skies in the morning, then a bit more cloud in the afternoon. Some forecasts show some elevated convection developing on Friday night and spreading across portions of western Manitoba and the Interlake. If that does form, it will likely remain north of Winnipeg but will bring some cloud and chances for showers to portions of the province through the morning hours.

A low pressure system crossing the Prairies will likely bring unseasonably warm conditions to the region on Saturday
A low pressure system crossing the Prairies will likely bring unseasonably warm conditions to the region on Saturday

A cold front will push through the Red River Valley late in the afternoon and through Saturday evening, bringing with it the chance for some showers or thunderstorms. At this point, there looks to be minimal chances for severe weather with under 1000 J/kg of MLCAPE forecast and bulk shear values near 20 kt.

The potential pitfall for Saturday’s forecast will be if thicker smoke once again moves into the region. It’s hard to tell at this point whether or not it will. Most guidance suggests it will primarily remain further north, but cold fronts can concentrate smoke ahead of them, so we’ll simply have to wait and see. If thicker smoke ends up returning, temperatures will be cooler and the chances for showers or thunderstorms diminish.

For Saturday night, Winnipeg will see winds diminish and temperatures head to a low near 16°C with a slight chance of showers continuing overnight.

Sunday will bring mostly cloudy skies to the region as an upper trough swings through. A small chance for showers is likely to continue into the morning, followed by clearing skies through the afternoon. Temperatures will be much cooler with a high near 23 or 24°C as northerly winds of 30 gusting 50 km/h move into the region. Temperatures will head to a low near 12°C on Sunday night under clear skies.

Long Range Outlook

Southern Manitoba will be under a northwesterly flow through the first half of next week which should bring clearer skies and near-seasonal temperatures. An upper-level ridge will push eastwards mid-week, bringing warmer weather back to the region alongside the potential for more smoke.

Winnipeg’s seasonal daytime high is currently 25°C while the seasonal overnight low is 12°C.

  1. Many places in the air mass we’ll find ourselves in today saw visibilities of 8 to 16 km through the day yesterday.

Hot Weather Returns

After a very brief cool-down, Winnipeg will see temperatures soar back into the 30s as a hot and hazy air mass returns across the Prairies from British Columbia.

A warm front pushing eastwards across southern Manitoba today will send temperatures in Winnipeg back towards 30°C this afternoon. With low humidity and winds out of the south-southwest around 20 km/h, it will be a rather nice summer day out there. Skies will remain sunny today, however a little haze may move into the Red River Valley this afternoon.

With this spell of warm weather, upper-level winds will once again be transporting smoke eastwards from the British Columbia forest fires. At this point, it looks like the worst of the smoke will remain west of the Red River Valley, particularly over Alberta and Saskatchewan. Winnipeg will likely see hazy conditions move in for Thursday, though, and southwestern Manitoba may see a more concentrated smoke event.

Winnipeg will continue to see clear skies tonight as winds taper off and temperatures drop to a low near 17°C.

Thursday will bring partly cloudy skies to Winnipeg but the more noticeable thing will be the persistent haze entrenched over the region. Temperatures should climb to a high near 30°C again with winds out of the northeast at 15 to 20 km/h. Temperatures will then head to a low near 17°C on Thursday night under clear skies.

Hot conditions will be back in place across the southern Prairies on Friday
Hot conditions will be back in place across the southern Prairies on Friday

By Friday, all indications are that even warmer weather will move into the region, pushing daytime highs to around 33°C under sunny, hazy skies. Winds will pick up out of the south-southwest to around 20 km/h through the day with a few clouds moving in for the evening. Winnipeg will see a warm night with a low near 19°C and increasing cloudiness.

Long Range Outlook

Saturday looks to bring another hot day with mixed skies and a chance of thunderstorms in the afternoon and evening hours. Cooler temperatures will move in for Sunday, kicking off a week of mostly near-seasonal temperatures and benign weather. After this roller coaster of temperatures over the past week, a week of not to too hot and not too cold sounds pretty good!

Winnipeg’s seasonal daytime high is currently 25°C while the seasonal overnight low is 12°C.

Get The Sunscreen Out: Summer’s Back

Here comes the shortest forecast we’ve written in a while: summer is making a big comeback in Winnipeg as the forecast — both short and long-range — holds practically nothing but sunshine and warm temperatures.

Winnipeg will see a trio of beautiful days ahead as two features keep skies clear and slowly warm things up. The first is an upper-level ridge over Manitoba and the second is a high pressure system in Ontario that continues to exert its influence over southern Manitoba. These two features combined together will keep things sunny, and as the surface high slowly moves off to the southeast, temperatures will climb back into summer-like values.

500mb Winds with Jet Stream Annotation valid 15Z Friday September 8, 2017
The jet stream lifts far to the north of Winnipeg, creating an upper-level ridge that is producing clear skies over the eastern Prairies.

So both today and Saturday will bring nothing but sunshine to Winnipeg & the Red River Valley with high temperatures of 23°C today and 26°C on Saturday. Winds will be out of the south both days, to around 20-30 km/h today and 30-40 km/h on Saturday. Expect lows near 9°C tonight and near 15°C on Saturday night.

We could see a few clouds on Sunday morning, but overall the day should be fairly sunny. The only fly in the ointment could be a thick layer of smoke spreading in from the west. Temperatures may reach as warm as 30°C, but if there ends up being a lot of smoke it could be a few degrees cooler than that. Winds will continue out of the south at around 30 km/h. A cold front will swing through on Sunday night, bringing some clouds and a chance of showers to the region, however no significant rain is expected with the passage of the front.

Long Range

Monday looks to bring mixed skies and lighter winds in the wake of the cold front with temperatures slightly cooler than Sunday. Things then clear out for Tuesday and temperatures continue to remain above-normal through mid-week. A disturbance developing over the Prairies on Wednesday into Thursday will then likely begin bringing more seasonal temperatures, increased cloud, and a chance of showers back to the Red River Valley for the end of the week.

The biggest question mark will be how much smoke ends up in the region, though. With westerly winds, a fair amount of the B.C. forest fire smoke may end up making its way here, and early indications are that there is the potential for it to be the most significant smoke event for Winnipeg so far this year. We’ll be keeping an eye on it!

Winnipeg’s seasonal daytime high is currently 20°C while the seasonal overnight low is 7C.

A Smoky Transition Back to Summer Heat

Today will be a bit of a mixed bag here in Winnipeg as a dying cold front completes its slump into Southern Manitoba bringing a chance of showers alongside another batch of forest fire smoke gradually working into the Red River Valley. Fortunately, winds will become more southwesterly as the week progresses, pushing the smoke to our north and bringing back hot summer weather to the area.

Today will start off with a slight chance of showers or thunderstorms until around midday after which the clouds will start pushing off to our southeast and see increasingly smoky skies build in. Temperatures will only climb to around 21°C today and then dip down to the low teens tonight.

NOAA 1hr. Vertical Smoke Forecast valid July 08, 2015 7PM EDT
The “total smoke” product from NOAA is forecasting a thick layer of smoke across Southern Manitoba by this evening.

Thursday and Friday will herald the return of summer. Winds will shift more westerly to southerly and begin tapping into warmer air to our south. There should be a deep enough layer of southerly winds to push the smoke north of Winnipeg through the day. Temperatures will be soaring into the upper 20’s on both days under mainly sunny skies.

The biggest difference between Thursday and Friday will be the humidity; while dew points in the mid-teens on Thursday will make it feel slightly humid, it’s expected that dew points will climb up to the 20°C – or even a bit higher – for Friday, making it feel downright tropical out there.

Overnight lows on Thursday & Friday will be in the upper teens.

Unsettled Weekend?

Weather models are pointing towards a potentially unsettled weekend as a large upper-level low lifts northwards into Alberta with a deep trough extending southeastwards across the Prairies.

GDPS 24hr. QPF valid 00Z July 13, 2015
Total precipitation forecast from Saturday evening to Sunday evening from the GPDS.

It’s not worth getting caught up in details at this point when dealing with a large, highly convective system such as this. The main thing to take away is that with a large low lifting into Alberta, it’s likely our weekend will continue humid, warm and potentially bring some wet weather.