Hot Summer Weather Returns

Hot and increasingly humid weather is on the way for Winnipeg, bringing sweltering summer heat and unsettled conditions.

Summer will return in full force to Winnipeg today. An approaching low pressure system moving in from Saskatchewan has drawn significantly warmer air northwards overnight, and will continue to tap into a hot and increasingly humid air mass through the day. Temperatures will quickly climb into the mid-20s today, then head towards a high near 30°C. Dew point values – a measure of the humidity – will also climb into the 17-19°C range by the late afternoon. This is high enough that it will start to feel muggy outside and it will produce a humidex value in the mid-30s.

High dew points will bring muggy conditions to southern Manitoba this afternoon

All this heat and humidity will, naturally, result in fairly unstable conditions from the Manitoba Interlake all the way south to the American border. MLCAPE values will climb into the 2000 to 2500 J/kg range by late afternoon, but a capping inversion of at least 60 J/kg should keep everything suppressed until late in the day. Shear is excellent in the Interlake with 0-6 km values in the 40 to 50 kt range with south-southeasterly winds at the surface veering to westerly aloft. Further south in the Red River Valley, shear values aren’t quite as favourable with 0-6 km values in 30 to 35 kt range and the capping inversion is slightly stronger.

As the Saskatchewan low tracks into western Manitoba in the afternoon and onwards to the Interlake, it will likely support an area of thunderstorm activity. These thunderstorms will be strong to severe with primary threats of large hail and damaging winds, and – while not a marked threat – an isolated tornado is possible.

Further south in the Red River Valley, a trough of low pressure extending southwestwards from the low will move into the region late in the day. There’s still a whole lot of uncertainty as to whether or not any thunderstorms will be able to develop along it. If thunderstorms manage to develop along the trough, it would likely be in the early evening, west of the Red River Valley, then progress eastwards over the next several hours. These storms would be strong to severe with the primary threats of large hail and damaging winds. Again, that’s only if they’re able to develop. Either way, with enough of the recipe in place today, it wouldn’t be a bad idea just to keep an eye out in case Environment Canada issues any watches or warnings.

Some high-resolution models show a line of thunderstorms breaking out late in the day over southern Manitoba

Everything should clear out by late evening, and Winnipeg will head to a low near 20°C. More cloud cover will move in early Saturday morning as a new upper-level disturbance begins lifting into the region from the United States.

As the upper-level disturbance moves into Manitoba on Saturday morning, it will likely bring an area of showers or thunderstorms with it. Timing is uncertain on this right now, but it will likely impact the region beginning sometime mid-morning until the early afternoon. Once it moves out, it will leave behind partly cloudy skies. High temperatures will depend significantly on how quickly it can move through the region. Right now it looks like the high temperature will reach around 26°C once the sun gets shining in the afternoon. If the system moves through faster it may get a bit warmer, or if it’s slower than it might be ac couple degrees cooler. Skies will clear out for the evening as temperatures head to a low near 18°C.

A cold front passing through late Saturday night will bring more cloud back into the region for Sunday. Northwesterly winds near 30 km/h will lower humidity levels and bring a cooler daytime high in the low 20s to Winnipeg. Forecasts currently show the Red River Valley under mainly cloudy skies for much of the day with a chance of showers. The winds will ease in the evening alongside clearing skies. Winnipeg should see a low on Sunday night near 15°C.

Long Range Outlook

Seasonal to above-seasonal temperatures will return to start next week and persist through to the end of the week.

Winnipeg’s seasonal daytime high is currently 26°C while the seasonal overnight low is 13°C.

GDPS 2m Temperature Forecast valid 18Z Friday August 3, 2018

Warming For The Weekend

Winnipeg will see a single day of cooler than normal temperatures before they begin to soar back to 30°C and above for the weekend.

Temperatures will be cool today in Winnipeg as a high pressure system moves through the province behind the cold front that passed through on Tuesday morning. The high will clear out any remaining cloud and bring very light northeasterly winds to the region. Winnipeg should see a high near 22°C, followed by a low near 10°C tonight.

Thursday will be a transition day for Winnipeg. Near-seasonal temperatures will return to the region as a low pressure system develops over the western Prairies. This developing low will bring moderate southerly winds back to the region, drawing a more summer-like air mass northwards out of the American Plains. Winnipeg will see mixed skies with a high near 27°C, but that southerly wind increasing to 40 gusting 60 km/h will put a bit of a damper on things. Much of southern Manitoba will see a chance of showers or thunderstorms Thursday evening into the overnight as the low pressure system approaches. Winds will ease a bit into the 20 to 30 km/h range as temperatures head to a low near 18°C.

By Friday, Winnipeg will be back into full-fledged summer mode. The city will see partly cloudy skies as temperatures climb to a high near 32°C. Winds will be lighter than on Thursday, out of the south at just 15 to 25 km/h. Temperatures will remain warm on Friday night with a low near 19°C.

Long Range Outlook

The warmth that moves in on Friday will mark the beginning of a prolonged period of above-seasonal temperatures.

NAEFS 8-14 Day Temperature Anomaly Forecast — Valid August 8 to 15, 2018
NAEFS 8-14 Day Temperature Anomaly Forecast — Valid August 8 to 15, 2018

Broad upper-level ridging will develop over the coming week as the subtropical high moves into the central United States. This will sustain a broad dome of very warm air that will easily be spread into our region. Winnipeg will see highs in the low 30s this weekend, followed by upper 20s to mid 30s next week. Lows will remain warm in the upper teens.

Rain-wise, forecasts are showing a high probability of dry conditions. That said, thunderstorms are tricky things, and several upper disturbances rippling through over the coming weeks will bring a few chances for showers or thunderstorms.

Winnipeg’s seasonal daytime high is currently 26°C while the seasonal overnight low is 13°C.

Hot Start Followed By Big Cool Down

After a hot start to the week today in Winnipeg, a cold front passing on Tuesday will usher in much cooler conditions.

Temperatures will soar above 30°C today in Winnipeg as a broad area of low pressure moves through the region. A west-southwest flow will send highs up to around 31°C with comfortable humidity levels. Skies will remain mainly sunny, and those aforementioned winds will only be around 20 km/h. Temperatures will remain mild tonight with a low near 18°C.

Tuesday will bring more cloud to the region and near-seasonal temperatures. Temperatures will climb to around 27°C before a cold front drops through the region. The front will bring increasing cloud and begin cooling off temperatures. There will be a chance for some showers or isolated thunderstorms in the afternoon, but low moisture and dynamic support will limit the rainfall potential. Winds will be notable with northerlies up to 30 to 40 km/h moving in for the afternoon.

A sharp cold front will sweep southwards through the Red River Valley on Tuesday afternoon.

A high pressure system moving into the region will bring significantly cooler temperatures on Tuesday night wth lows heading back towards 10°C. Winds will gradually diminish to around 10 to 15 km/h on Tuesday night.

Wednesday will see mixed skies gradually clear, but temperatures will be markedly cooler with a high near 21°C. Winds will be light out of the north-northeast as the high moves through. Expect another cool night on Wednesday night with a low near 11°C and light winds.

Long Range Outlook

Temperatures will return back towards seasonal values for the remainder of the week, but forecasts are indicating that unsettled conditions will return to the region. A few disturbances moving through will bring the chance of showers or thunderstorms back to the region Thursday night through Friday.

Winnipeg’s seasonal daytime high is currently 26°C while the seasonal overnight low is 13°C.


Photo by Gabriela Parra on Unsplash

Great Summer Weekend Ahead

Winnipeg will see a beautiful weekend with a fair amount of sunshine, warm temperatures, and just a slight chance of a passing shower or two.

The general weather pattern this weekend will see a weak high pressure system moving through the Prairies. It will bring generally pleasant and mild weather to the region with highs in Winnipeg forecast to reach the upper 20s. Overnight lows will gradually warm as well, climbing into the mid-teens by the end of the weekend.

Winds won’t be a bother over the coming days, either, with light northerly winds shifting to westerly sometime Saturday night.

The region will see plenty of sunshine, with cloud cover following the ebb and flow of the temperatures. Generally sunny mornings will cede to afternoon clouds as temperatures warm up. In the evening, skies will clear as temperatures cool.

Lastly, while the chances for any one spot to see rain remain low, isolated to scattered afternoon showers are possible. It looks like they will be very hit and miss, so just keep an eye on the sky over the next couple afternoons in case a rouge shower passes through.

Long Range Outlook

The pleasant summer weather will spill over into the start of next week. Generally sunny conditions with daytime highs in the upper 20s will continue into Monday. A low pressure system passing through on Tuesday looks like it will bring showers or thunderstorms to the region followed by a return to seasonal temperatures and variable cloudiness.

Winnipeg’s seasonal daytime high is currently 26°C while the seasonal overnight low is 13°C.