Moderate to severe thunderstorms possible for the next three afternoon and evenings

Warm temperatures will continue across central and southern Alberta due to a well-supported ridge of high pressure situated over southern British Columbia, Alberta and Saskatchewan.

Warm temperatures will continue across central and southern Alberta due to a well-supported ridge of high pressure situated over southern British Columbia, Alberta and Saskatchewan. Daytime highs will range from 24 C to 30 C until the end of next week. After a historically wet June around the Edmonton region there is an ample amount of moisture in the ground that, when combined with this upcoming period of above seasonal temperatures, will serve as fuel for what could be some very large thunderstorms.

Areas along the foothills as well as the northern edge of that ridge will be the initiation point for the development of active weather later in the day on Wednesday, Thursday and Friday. On Wednesday, isolated cells are expected to form west of the QEII before tracking toward the Yellowhead. Calgary could see some brief periods of rain and/or thunderstorms activity later in the afternoon.

On Thursday, some rapidly developing storms are possible around the Calgary area in the afternoon. But Friday looks to be the day of greatest concern as the ridge strengthens and edges north into unsettled areas. A number of large storm cells may start to form west of Red Deer in the afternoon Friday with the possibility of the individual cells organizing and strengthening into one larger system that could roll through Edmonton.

The greatest threats would include large-sized hail, damaging wind, intense rain, and possible tornadic activity. Calgary will likely catch the southern edge of this system Friday with rain, hail, and wind posing the greatest threats.