Meteorological seasons are each three months long. Summer is June to August, fall is September to November, winter is December to February, and spring is March to May. Astronomically, summer starts on the summer solstice, which falls on June 21.
Let’s look at last month and examine how spring turned out across the Canadian Prairies, then turn to the long-range forecasts.
May across the Prairies, in one word, was “hot.” The last frost occurred in Manitoba during the first few days of the month. In Saskatchewan, it was later for Regina, on May 19, but earlier in Saskatoon, on April 30.
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In Alberta, Peace River saw its last spring frost on May 8, Edmonton on April 30 and Calgary on April 26. These are truly early dates across the Prairies. It’ll be interesting to see how long this year’s frost-free season will be.
All major stations reported mean monthly temperatures well above the long-term average. They ranged from 3.4 C above average at Dauphin, Man., to 5.2 C above average in Calgary. Winnipeg was the hot spot with a mean monthly temperature of 15.8 C, while Peace River was the cold spot at 13.6 C.
Another measure of May’s warmth is the number of days warmer than 30 C. Once again, Winnipeg was the hotspot, with five days over this mark. Regina and Calgary had no May days warmer than 30 C.
May was also a relatively dry month. Only two main locations reported above-average precipitation. Peace River was the wet spot with around 72 millimetres of precipitation, while Saskatoon reported about 52 mm.
Looking back at the forecasts, the best one was the CFS model that correctly predicted warmer and drier than average conditions in May.
Earlier, spring had a cold start across the Prairies, with March temperatures running far below average. April saw a bit of a warmup in the west. Alberta had average to above-average temperatures while Saskatchewan and Manitoba continued to deal with below-average temperatures. Then May rolled in with summer-like temperatures, but overall spring 2023 was colder than average simply due to the brutally cold March and April.
Precipitation this spring was below average in nearly all regions. Only Peace River reported above-average amounts, mostly due to one wet day in May.
The Old Farmer’s Almanac calls for near- to slightly-above-average temperatures, with summer starting off dry and getting progressively wetter. The Canadian Farmers’ Almanac calls for near- to above-average temperatures in June followed by above-average temperatures in July, then back to near- to above-average temperatures in August. Precipitation looks to be near- to below-average.
Among the more reliable weather models, the U.S. NOAA calls for average temperatures and precipitation this summer, with Alberta possibly seeing slightly above average temperatures. The CFS model calls for well-above-average temperatures in June, cooling toward more average values in July and August. Overall, it calls for near-average temperatures across the southern Prairies with above-average temperatures over more northern regions. Precipitation is forecast to be above average this summer.
The CanSIPS model is taking a different tack, calling for well-above-average temperatures to continue all summer, with near average precipitation over western regions and below average precipitation in the eastern Prairies and far northern regions.
As for my prediction, I would be rich if I could accurately forecast summer weather. An accurate long-range forecast is literally worth billions. Always keep that in mind that when someone says they can predict the weather. I lean toward the Canadian CanSIPS model, with its call for above-average temperatures this summer along with near- to below-average precipitation.
Daniel Bezte is a teacher by profession with a BA in geography, specializing in climatology, from the University of Winnipeg. He operates a computerized weather station near Birds Hill Park, Man. Contact him at daniel@bezte.ca.
