Upcoming warm, dry conditions not helping drought conditions or wildfire risk

After a week centred around inconsistent weather conditions, Calgary will experience a reset and return to seasonal conditions over the weekend.

The large low-pressure system that brought cold and wet conditions into Alberta Tuesday and Wednesday is still the main driver of our current weather – despite this low being centred over central Canada. The outer edges of the system extend as far west as the Rockies, and the counter-clockwise circulation around the low continues to grab colder air from the north and drive it south into the foothills.

As a result, the daytime high in Calgary on Friday is forecast to be nine-degrees below seasonal and wind will be primarily from the north.

The large low-pressure system that brought cold and wet conditions into Alberta Tuesday and Wednesday is still the main driver of our current weather – despite this low being centred over central Canada.

By early next week the weather pattern is expected to shift and warmer air should flow over the southern Rockies, dropping moisture on the B.C. side (as per typical adiabatic processes) and allow warm, dry air to settle over southern Alberta.

In the transition period on Sunday there is a chance of light and scattered rain throughout the region, however precipitation totals are likely to remain low.

By early next week the weather pattern is expected to shift and warmer air should flow over the southern Rockies.

The moisture from last week offered some relief in terms of offsetting short-term drought conditions, but according to Agriculture and Agri-Food Canada (AAFC) most of Alberta is still far too dry.

In their April 5, 2024 report, the agency explains most of central and southern Alberta are under long-term drought conditions, with some areas having received less than 50 per cent of the expected moisture from the end of Sept. 2023 until the end of March 2024.

Some communities east of Highway 2/QEII saw slight improvements in the size of their driest areas, however as of the most current drought monitor map (to March 31, 2024) “drought intensity” classifications in this area range from D2 (one in 10 year event) to D4, or the worst rating, which is a one in 50 year event.

In their April 5, 2024 report, the agency explains most of central and southern Alberta are under long-term drought conditions, with some areas having received less than 50 per cent of the expected moisture from the end of Sept. 2023 until the end of March 2024.

The months of May, June, July have historically been the wettest months around the Calgary area, bringing in more than half of the annual moisture, however moisture stores (snow pack, soil moisture) are critical in offsetting water shortages.

According to the AAFC “Concern for water supplies remains as we move into the growing season with many reservoirs reporting significantly lower than normal levels this winter.“

Drought conditions in Northern Alberta declined at an even faster rate, which is contributing to concerns for the upcoming wildfire season.

In the wildfire update from April 18, 2024, Alberta Wildfire Information Manager Christie Tucker noted Alberta started  the 2024 wildfire season with 64 wildfires still burning from last year, so “firefighters are entering this spring with a heavier fire load than usual.”

Twenty seven of those have been extinguished, leaving 37 holdover fires.

Tucker said drought conditions enhance wildfire risk as dry trees and grasses can burn – “particularly in the high winds [as of late].”