Patience will be rewarded heading towards the end of the week as above-normal temperatures[1] are poised to return to Southern Manitoba thanks to a low pressure system that will push across the Central Prairies. In addition to the warmer weather, the chance for some wet weather, possibly even thunderstorms, will make a return as well.

Wednesday

14°C / 3°C

Mainly cloudy & cool; clearing in the afternoon

Today will be the coolest day of the next few as we remain on the periphery of a large pool of Arctic air. Plenty of stratus cloud will persist in Winnipeg until this afternoon; afterwards we’ll see clearing skies and a high temperatures near 14°C. Another chilly night lies ahead with temperatures dropping to the 3 or 4°C mark under continued clear skies.

Thursday

20°C / 16°C

Increasing cloudiness with a breezy southerly wind

Thursday will mark our entry into warmer weather. Gusty southerly winds will develop ahead of a warm front that will gradually push eastwards through the day. Winds will peak at around 30–40km/h with the potential for gusts to around 50km/h. Much of the day looks fairly sunny which will help temperatures climb to around 20°C by late in the afternoon, but by mid-to-late afternoon clouds will noticeably begin thicken up.

The potential for thunderstorms returns Thursday night, but it’s conditional and will be mainly confined to southwestern Manitoba. Substantial mid-level instability will couple with a strong low-level jet (LLJ) in the evening to attempt to produce thunderstorms. While many severe weather parameters output by various models look fairly impressive, there are a few concerns I have with development, somewhat related to each other:

1. Even lifting from the low-level jet, convection looks capped. If lift is strong enough to break through the cap and taps into the mid-level instability, then strong to severe storms could be possible, but…
2. Synoptic lift looks uncertain. While the LLJ is forecast to be quite strong at 25–35kt, deeper synoptic lift looks uncertain. Some models hint at a shortwave rippling through the region on Thursday evening, which could help initiate thunderstorms if true.

If thunderstorms did manage to initiate over southwestern Manitoba, they would have a chance of becoming severe, with the main threats being large hail and strong winds. As the system pushes eastwards overnight, the chance for showers or thunderstorms will spread into the Red River Valley. The thunderstorm potential will diminish as the system moves eastwards.

With all the cloud, potential precipitation and breezy winds moving through overnight, temperatures will remain fairly mild, only dipping down to the mid-teens.

Friday

22°C / 9°C

Chance of morning showers; afternoon clearing

Friday will continue the pleasant weather. A slight chance of showers may persist into the morning from Thursday night, but skies should quickly being to clear out, leaving us with partly cloudy to mixed skies for the remainder of the day. Daytime highs will climb into the low 20’s without too much wind to worry about.

Temperatures will drop just under 10°C on Friday night under mainly clear skies.

The Weekend Ahead

The coming weekend looks great! Mostly sunny skies will dominate through the weekend with daytime highs continuing to sit in the low 20’s and overnight lows in the mid-to-high single digits. It will be a beautiful late-September weekend, so get out and enjoy it!

After an early blast of fall-like weather earlier this week, Winnipeggers will be pleased to hear that summer will quickly return to Southern Manitoba.

Wednesday

24°C / 13°C

Warming up with some afternoon cloud

Thursday

27°C / 15°C

Mainly sunny. Off-chance of a late-day shower

Friday

23°C / 9°C

Morning cloud with gradual clearing

There’s little to say about the weather heading our way the next few days. Today will be a pleasant day with highs near 24°C with some afternoon cloud and winds gradually increasing out of the south to 20–30km/h. Temperatures will dip to around 13°C tonight with partly cloudy skies.

Tomorrow will be a warmer day across the region with highs near 26 or 27°C. A cold front will begin working its way through western Manitoba through the day and push into the Red River Valley overnight. Despite ample surface moisture, stronger mid-level dynamics remain further north in the Interlake, so it’s likely that the front will be relatively unimpressive through the Red River Valley, but there will still be an off-chance of some isolated strong thunderstorms. In general, showers will be much more likely along the front as it pushes eastwards. Temperatures will drop into the mid-teens Thursday night in Winnipeg with a small chance of showers.

Friday will be a cooler day thanks to the cold front that will push through on Thursday. Highs will be limited to the low 20’s and the day will start off with cloud that will then gradually clear throughout the day. The low on Friday night will drop back into the high single-digits.

This week will start out on a cooler and more unsettled note, but then conditions will begin to change. Hot weather looks set to return before the weekend.

Monday

Monday

24°C / 10°C

Showers and Thundershowers

Today will be quite unsettled, with a good chance of showers and thundershowers. Skies will start out mainly sunny in the morning, but daytime heating will quickly cause the atmosphere to become unstable, allowing widespread convective precipitation to develop. For the most part the precipitation will be in the form of showers, but there will likely be some thunder in lightning in some of the cells as well. Some small hail could even occur in some of the stronger cells. This activity will die off in the evening, with little rain expected overnight. High temperatures today will be in the low to mid twenties with a breezy north-west wind.

Tuesday

Tuesday

23°C / 11°C

Mix of Sun and Cloud with Chance of Showers

We may see some more shower activity on Tuesday, but it will be less widespread than Monday. Most areas will see a mix of sun and cloud through the day, with temperatures in the low, or maybe mid, twenties. The wind will once again be breezy and from the north-west.

Wednesday

Wednesday

26°C / 14°C

Mainly Sunny

Wednesday looks like quite a nice day in southern Manitoba. The heat will begin to return, with high temperature climbing up into the mid and upper twenties. Skies should remain mostly sunny, though the odd pop-up shower can’t be ruled out. The wind should be fairly light, with the direction being somewhat variable as we’ll be under the eastern edge of a high pressure ridge.

Long Range

The current long-range forecast looks good for those that like the heat! Models suggest that hot weather will continue from late this week into next weekend. We’ll likely see humidity gradually build late in the week as well. We may even see another risk of strong storms at some point once that humidity starts to return, but it’s too early to say if and when that might occur.