Both the daytime highs and overnight lows in Calgary will remain above seasonal to kick off the long weekend, prompting a yellow-level heat warning to be issued by Environment and Climate Change Canada (ECCC). According to ECCC, daytime highs will sit in the low to mid 30s for the Calgary area and the mid to high 30s for the southeast corner of the province. Heat warnings are issued when both the daily highs and lows in a region are forecast to meet or exceed threshold values for a prolonged period of time – and where that heat will elevate health concerns. In their warning, the national weather agency advised people to take the following precautions: The main weather-maker for the area is a blocking pattern in the upper levels that includes a ridge of high pressure situated over the southern border of the western prairies. Under that ridge the weather conditions will remain stable with very little cloud cover and only a light wind. Rain and/or thunderstorms are expected to ride along the outer edge of the ridge on Friday in central British Columbia, northern Alberta and northern and central Saskatchewan. Wildfire smoke from wildfires in B.C. and Alberta is producing higher-levels of particulate, and just after 7:30 a.m. Friday, yellow-level air quality warnings were expanded across the region. Long-duration exposure to wildfire smoke is concerning to everyone, but certain groups are especially vulnerable. “People more likely to be impacted by wildfire smoke, including people aged 65 and older, pregnant people, infants and young children, people with an existing illness or chronic health condition, and people who work outdoors, should reduce or reschedule strenuous activities outdoors and seek medical attention if experiencing symptoms,” ECCC said. By Saturday, the anchoring low in the Pacific basin will swing into northern Alberta, and where that cooler air collides with the warm, dry and stable air mass there is the potential for moderate to severe thunderstorms. In Alberta, those storms will likely initially cover the area from Edmonton to Fort McMurray before the trailing cold front tracks south across the QEII Highway on Saturday night. In Calgary, this will translate to stronger north wind late Saturday with a rapid drop in temperatures and a slight chance of precipitation Sunday. The daytime high in Calgary on Sunday will be 11 C colder than the high on Saturday and will remain around the 20 C mark for Monday. The normal high in Calgary is 24 C with a low of 10 C.
