`Intense bursts of heavy snowfall' in forecast after warm weekend

Precipitation, cooler temperatures predicted amid swing in conditions

Weekend warmth in the highteens is expected to give way to chillier temperatures, rain and flurries beginning Monday.

Environment Canada meteorologist Rob Griffith said an upper ridge with westerly flow over what has been a “very pleasant” weekend led to dry and warm temperatures for much of Alberta.

Despite being forecasted to be mainly sunny with a high of 15 C and low of 0 C, a low tracking into the prairies from the southwest carries with it a 60 per cent chance of showers to the Calgary area late Monday afternoon, said Griffith.

With precipitation falling and cooling temperatures, he said, “What happens after that will be a lot more hard to bear — the possibility of some snow for Calgary on Tuesday.”

It is expected around five to 10 centimetres of snow will fall in Calgary on Tuesday, with higher amounts west of the city, possibly within the 15 to 25-cm range in places like Bragg Creek.

“This storm will be fairly convective, so it will be some intense bursts of heavy snowfall once it's getting going,” Griffith said.

Griffith noted that forecasts remain fairly uncertain, as it's difficult to get a handle on exact amounts of precipitation. Many surfaces may also be warm enough for snow to melt on contact, he said.

Swings in conditions and temperatures are quite normal for this time of year, especially in southern Alberta and near the Rocky Mountains, Griffith explained.

“The averages are made up of extremes.”

Dry spells, precipitation unlikely to tip drought or wildfire scales

Due to dryness many thunderstorms end up being higher in the atmosphere, said Griffith.

“Precipitation's falling from a fairly high level, it's dry, sometimes it doesn't even make it to the ground — but there's still that lightning happening,” he said.

Lightning can hit the ground and spark wildfires, and dry conditions elevate the risk.

The province is heading into what some call “spring dip,” the dry period between the end of April and beginning of May when snow is gone and trees suck up moisture.

Alberta Wildfire placed the whole forest protection area of the province on a minimum of a forest advisory earlier this week, citing caution due to dry conditions.

More than 1,000 wildfires in Alberta last year burned about 22,000 square kilometres across the province, about five times the five-year average.

The 2023 wildfire season was the worst on record for Canada, burning more than 15 million hectares across the country and forcing more than 230,000 people from their homes.

An Alberta Biodiversity Monitoring Institute report found that the 1,088 wildfires in Alberta last year destroyed habitat for threatened species, and will change the makeup of the province's forests for decades to come.

Griffith believes warm and dry El Niño conditions are waning, and said there could be a shift toward the opposite, La Niña by June or August, which generally brings heavy rains to Western Canada.

Cumulative precipitation for Calgary from September 2023 to March 2024 was 116.8 millimetres, or about 75 per cent of the normal of 155.5 mm. He said despite those numbers being dryer, they are statistically normal.

Average monthly precipitation is highest in June for Alberta at around 94 mm, and lowest in January at 9.4 mm, said Griffith.

In terms of droughts or wildfires, he said one warm, dry weekend — or one bout of precipitation — isn't going to tip the scales one way or another.

“It all adds up in the end, right? Every system that brings precipitation will help, but one-off isn't going to make a big change.”

Preparation has been ongoing as the province declared the start of wildfire season 10 days earlier this year, on Feb. 20.