Severe thunderstorms possible Friday evening and early Saturday

A low pressure system along the Pacific coastline will be the main cause for concern in southern Alberta Friday night.

A shortwave trough in the exit region (the east side of the trough) will head straight into the southern border, where amble energy could aid in storm development.

Daytime highs in southern Alberta are forecast to reach the low 30s Friday, with the trough arrival coinciding with the end of the day when warmer air will be rising.

This increased water vapour in the atmosphere, combined with stronger and variable winds has the potential to create damaging thunderstorms. These storms are expected to be fast-moving with the greatest threats including heavy rain, medium to large-sized hail and damaging winds.

Calgary is likely to see some evening showers and thunderstorms with five to 10 millimetres of rain expected to fall.

As of 8 a.m. Friday Environment and Climate Change Canada had not issued any severe thunderstorm watches or warnings for the region – but this is likely to change.

The highest accumulations in Alberta will be closer to the foothills, with some areas in central Alberta potentially being impacted by a second round of rain as the low swings back around before heading east on Sunday.

Calgary’s temperatures will return to seasonal on Saturday and Sunday before another system moves in on Tuesday.

The average daytime high for Calgary right now is 22 C with a low of 9 C.