Fall like weather to be booted out by hot and humid summer like conditions that will return midweek.

Southern Manitoba is continuing to be affected by fall like weather that has dropped our temperatures well below average for this time of year. All thanks to a stubborn cold low and trough that has made a impact 

Severe weather threat to end the heat and humidity. Cooler weather on the way for early week.

Heat and humidity continue to affect a large portion of southern Manitoba including the city of Winnipeg, as a result a heat warning is in place for a large portion of southern Manitoba. A cold front is expected to slice into this heat and humidity and provide relief, but not before storms. 

A heat warning is in place for the large majority of southern Manitoba and into NW Ontario please take as many precautions as you can to make sure you stay as cool as possible, drink water, stay in the shade and wear light clothing. Areas of western Manitoba to the Ontario border are also in a severe thunderstorm watch. There is a high concern though as we get into the late afternoon towards the evening within the next hour, severe thunderstorm development is likely as a cold front slides into the hot and humid airmass. CAPE values in excess  of 2,000-3,000 J/Kg, LI’s of -5 to -9 will make for explosive thunderstorm development with dewpoints between 17 and 21C sufficient moisture should be there to sustain storms as they continue to form. Shear will be a concern with shear in the order of 40knots, and veering in some areas with wind from the east there is a chance for storms with tornadoes. The trigger will finally be the cold front that will be moving into the soupy environment. 

As a result expect severe thunderstorm development to continue as the front slices into the hot and humid airmass, super cells are likely in initial stages of development there will be a risk of heavy rain, wind gusts up to 120km/h, , hail up to golf ball or baseball sized hail. There is a risk of tornadoes as these storms move east into the Red River Valley, there is a chance Winnipeg may be affected by these supercellular storms as well. I will monitor this as the evening goes on. Once storms organize (depending on how Far East before they line out) expect a squall line with multiple bowing segments to move east into the eastern portions of southern Manitoba. Wind gusts over 100km/h, hail up to golf balls and torrential rains will be possible. Once the cold front moves east into Ontario, cooler calmer conditions will set in with a nice NW Flow. 

Cooler and more seasonal temperatures will take over for the beginning of the week with highs in the low to mid 20’s. Rain and storm chances return late week. Enjoy the cooler weather when it comes! -Mike

Significant heat and severe weather on the way Today.

Significant high temperatures and humidex readings will be continuing to effect a large portion of southern Manitoba through the day Saturday and into early Sunday. A cold front sliding into the airmass could make for volatile weather that will flush out the heat and humidity. 

03Z HRRR showing the High humidex readings for much of southern Manitoba and the eastern Prairies. (Dew point and Temperature combined, to create feel like temperatures).

Southern Manitoba is in for a interesting day Saturday heat and humidity will continue to build into the region ahead of a cold front that will be entering areas of the Red River Valley in the evening. Heat warnings are in effect for a large portion of southern Manitoba as the hot and humid airmass is in place. Temperatures in the mid 30’s with dewpoints in the mid 20’s are making humidex readings feel close to the mid 40’s. People are advised to stay inside and keep as cool as possible, if you are to go outside please stay as hydrated and seek shade as much as possible!! The vulnerable including the elderly, children and homeless people are advised to take extra precautions to avoid heat stroke. A cold front will be going through this hot and humid air mass this evening and with it significant severe weather is possible. Looking at the severe weather indicies the moisture we have dewpoints in the low to mid 20’s, Humidex readings in the low 40’s. CAPE of 3,000 to 6,000 J/Kg, Lifted index’s of -9 to -12, and shear on the order of 10 to 40 Knots. The trigger this evening will be the cold front moving east across the Red River Valley into Southeastern Manitoba. There is a weak cap in place this evening in southeastern portions of Manitoba and as the cold front moves east the cap is expected to weaken. Severe thunderstorm development may occur east of the city of Winnipeg this evening if the front moves east fast enough, also depending on the cap. Considering most models will have the cap eroding around 21z (4pm-7pm) in the Red River Valley and east supercell storms may have a window to form within that timeframe. However most models show storms not developing until the front gets to the southeastern portion of Manitoba into NW Ontario by 8pm. Regardless once storms form they will pose a significant risk of becoming supercellular with gusts over 120km/h, Heavy rainfall over 50mm an hour, hail up to the size of golf balls or larger, and potential tornadoes. I’ll continue to update this as needed, in the comments below, on Twitter and Manitoba Weather Centre.

Cooler conditions will arrive for the day tomorrow with temperatures in the mid to high 20’s and humidex readings in the mid 30’s should be with us until mid week, chances at showers and thunderstorms return mid week into late week for us. Stay cool and stay sky aware!

Blog post on Heat and severe weather on the way later today

A heat wave will be coming to Southern Manitoba for the end of the week and severe weather threat  will be arriving on the day Saturday. Heat and Humidity levels will start increasing and humidex readings could be in the mid to high 40’s near 50C. will All forms of severe weather will be possible Saturday afternoon and evening, including Tornadoes, risk area at this moment appears to be the Red River Valley and southeastern Manitoba. I will update you more tomorrow.