Mother's Day weekend will be the warmest weekend so far this year

Typical of southern Alberta in the spring – the weather this week is anything but consistent.

Tuesday’s daytime high in Calgary was 7 C, or just under 10 C below seasonal, compared to the daytime high on Friday which will be more than 10 C above seasonal.

A ridge of high pressure situated in southern British Columbia is extending into central Alberta and offering a well-timed period of stability for the Mother’s Day weekend.

Wind will be mild, sunshine will be plentiful, and daytime highs are expected to sit in the mid to high 20s for most of southern Alberta.

There is a concerning component to this warmth – in that it is happening so rapidly and to such a high degree.

Avalanche Canada has issued some “high risk” ratings for two areas west of Calgary – including in Banff National Park and Lake Louise, due to what they describe as “a period of all melt, no freeze.”

The agency explains on their website, “as freezing levels spike over the weekend, so will the avalanche hazard.”

There is a minimal chance of light and scattered rain in Calgary on Saturday, and Sunday evening could include an isolated thunderstorm or two, but daytime highs both days will be 24 C.

That ridge will track east by Monday and temperatures are expected to return closer to seasonal. As cooler air moves in there is a better chance of rain, but accumulations should be limited to two to five millimetres for Calgary.