Calgary to see warm Friday with potential for severe weather later in the day

There is a reason the phrase "the perfect storm" was coined, and Friday will be a boom or bust day to prove it.

Initially, conditions in southern Alberta will be great.

Calgary’s daytime high of 23 C should be reached early in the day, but if certain ingredients align "just right," what begins as a nice start could turn into an afternoon with large-sized hail, strong wind and potential tornadic activity in the province.

A low complex off the coast of British Columbia has started to show a negative-tilt (a northwest to southeast orientation of the trough) and this is expected to intensify throughout the day Friday.

Negatively-tilted troughs are often associated with severe weather, as they provide the ingredients for supercell development through heightened instability and strong wind shear (a change in wind direction with height).

The combination of a negatively-tiled trough moving over the physical barrier of the Rocky Mountains, along with an ample source of moisture east of the foothills, may create the "perfect storm" or severe weather on Friday.

On the other hand – storm development may remain capped throughout the day.  

As of 7:30 a.m. Friday, no weather watches or warnings had been issued for southern Alberta, but it would be reasonable to expect that to change as daytime highs are reached early.

By Saturday, the low heading into Alberta will rotate through central Alberta, and thunderstorms are likely through much of the province, including Calgary.

Instability will stick around for Father’s Day with rain tapering off and stronger winds on top of a daytime high that will be 9 C below seasonal in Calgary.

Overnight temperatures in Calgary will be around 4 C, and even cooler in the mountains, with some models suggested mixed precipitation is possible in the overnight hours.

Temperatures will return to average ranges (20 C and 7 C) by the end of next week.