Hot, increasingly humid weather will begin working it’s way back into Southern Manitoba as a southerly flow at the surface, advecting moisture northwards from the US Plains, combines with an upper ridge over the Prairies that will work to crank up the heat.
Model winds at 500mb showing the strong upper-level ridge forecast over the Prairies on Thursday.
Today
Wednesday
28°C /
15°CSunny.
We’ll see a pleasant day today with sunshine dominating the skies and a light northwesterly wind. Temperatures should climb up to around 27°C while the northerly winds keep the humidity down making it a very comfortable summer day. Skies will remain clear overnight as we drop to a low of around 15°C. There will be a very slight chance of a thundershower or two in the Red River Valley through the afternoon hours, but if they do develop they’ll most likely be tied to areas along the western escarpment and northwards towards Riding Mountain park. There would be a very marginal chance of any of these storms becoming severe; if any were to the main threats would be heavy rain and large hail.
Thursday & Friday
Thursday30°C /
19°CSunny & increasingly humid.
The heat will build a little more on Thursday, but the real big difference will be the humidity which will become very noticeable as the winds shift around to the south on Wednesday night and allow the dew point to start climbing. They should reach the mid-to-high teens by Thursday evening which, when combined with our expected daytime high of 30°C will make it feel more like the mid-to-high 30’s. No storms are expected as a strong cap keeps everything in line.
Friday
28°C /
14°CA mix of sun and cloud; showers or thunderstorms with passage of cold front. Very humid until front passes.
Friday will be the most active day of the week as ample heat and humidity are in place ahead of a moderately strong cold front that will work across Southern Manitoba through the day. It looks likely that storms will initiate on the front fairly early in the day (perhaps even by late morning if nocturnal storms don’t just march out of North Dakota and continue through the day) and pose the risk of becoming severe as they will have ample energy available to them.
High CAPEs combined with ample bulk shear (0–500mb bulk shear values are expected to be in the range of 50–60kt) will allow storms to organize quickly and introduce the threat for large hail and strong winds. Shear values are generally running parallel to the front, which means slow frontal motion could produce training thunderstorms that may produce localized flash flooding. The threat for tornadoes looks fairly low given that winds right near the surface may not be able to move into a favourable direction due to the orientation of the front and tilt of the entire system. While tornadoes can never be ruled out of severe thunderstorms, at this time it doesn’t look like the threat should be considered one of the primary threats for Friday.
The day may be more cloud than sun depending on how convection develops to our south and west on Thursday night, but we should see a high temperatures anywhere from 25°C to 28°C before the front comes through. The passage of the front will bring northerly winds which will flush out a lot of the humidity that will have built up over the prior days which should make things quite a bit more comfortable. Things will clear out overnight as we drop to a low in the mid-teens.
The Weekend
Looking ahead to the weekend, we’ll see plenty of sunshine return with highs climbing in the 27–30°C range with comfortable humidity. It looks great. Keep tuned here and to our team on Twitter (@WeatherInThePeg, @steinbachwx and @lovestormsMB) for updates and thoughts on Friday’s severe weather potential. Until then, enjoy summer!
