Our risk for strong to severe thunderstorms will continue this weekend as high heat and instability build over the southern Prairies. Any rain from the storms is good news for areas that have fallen into a major drought in recent months, though the heavy rain could also lead to localized flooding issues for some. More on the weekend storm threat and just how hot it’ll get, below.
THIS WEEKEND: MULTI-DAY THUNDERSTORM THREAT AMID EXTREME HEAT
Severe thunderstorms will be possible for southern Alberta and Saskatchewan once again on Saturday as a low pressure system advances north from Montana into southern Saskatchewan.
Isolated to scattered thunderstorms will develop through the late afternoon to early evening hours, with a greater potential for these to turn severe into the evening.
Dynamics are favourable for supercells in southern Alberta, bringing the risk for large hail.
By Sunday, the storm threat pushes east into southern Saskatchewan and southern Manitoba as the low pressure system continues to track eastwards. With the extreme heat, there will likely be a cap in place, but storms that are able to break through will likely turn severe very quickly.
WIDESPREAD HEAT WARNINGS IN EFFECT
In addition to the multi-day thunderstorm threat, days of high heat and tropical humidity will spread from west to east across the southern Prairies this weekend. Daily temperature records and dangerous humidex values are likely.
Heat warnings are in effect across Saskatchewan as a heat dome in the southern U.S. will nose the northern part of the ridge into the Prairies.
Widespread low to even mid 30-degree temperatures are forecast for southern and central Saskatchewan on Saturday while southern Manitoba will be the focus for the mid 30°C heat on Sunday.
"Extreme heat affects everyone," says Environment and Climate Change Canada (ECCC) in the heat warning.
"The risks are greater for young children, pregnant women, older adults, people with chronic illnesses and people working or exercising outdoors. Watch for the effects of heat illness: swelling, rash, cramps, fainting, heat exhaustion, heat stroke and the worsening of some health conditions. Drink plenty of water even before you feel thirsty and stay in a cool place. Check on older family, friends and neighbours. Make sure they are cool and drinking water."
Much cooler conditions are expected next week, though remaining warmer at times for parts of Manitoba.
Be sure to check back for updates this weekend as we continue to fine tune the forecast details on the storm timing and severity.