Calgary weather: Thunderstorms possible Tuesday and Wednesday; highs in 20s by weekend

The start of this week will include some unsettled weather, with highs dropping to 12 C in Calgary on Wednesday and scattered showers and thunderstorms forecast across the province.

A low-pressure system is expected to develop in the foothills during the day Tuesday before heading into Saskatchewan overnight. That low will meet with a system cutting through northeastern Alberta and northern Saskatchewan.

Daytime highs around southern Alberta will sit close to seasonal values on Tuesday and drop down to the low double digits by Wednesday.

Calgary may see some precipitation Tuesday, especially toward the end of the day and overnight, but if it does, accumulations should be minimal.

Areas along the Alberta-Saskatchewan border south of the Yellowhead and north of the Trans-Canada Highway will likely record heavier accumulations during this time.

A prominent high-pressure system will move from the eastern Pacific into western Canada by the end of the week, helping to push temperatures back into the low 20s by the weekend.

The normal range in Calgary this time of year is 17 C for a high and 4 C for a low.