An upper-level blocking pattern situated over North America is funneling heat into a good portion of Canada. Yellow-level heat warnings have been issued for areas south of Calgary and in Ontario. In the advisory for the southeast corner of Alberta Environment and Climate Change Canada (ECCC) explained, “Daytime high temperatures will range between 33 and 38 degrees Celsius, with overnight lows expected to range between 14 to 17 degrees Celsius.” Daytime highs around Calgary will sit in the high 20s to low 30s on Thursday, and above 30 C on Friday and Saturday. Wildfire smoke is raising health concerns across the B.C. interior and into the north-central region of both Alberta and B.C. leading to both orange and yellow-level air quality warnings being issued. The conditions in southern Alberta will remain mostly stable and clear for the next few days, with a slight chance of heightened instability along the central and northern foothills later in the day Thursday. A surface low pressure system could form near Calgary throughout the day and by the evening would likely fuel any thunderstorms that form along the foothills. Convective activity is also possible in the far southeast corner of Alberta as well as in northern Alberta on Thursday night. The next chance of active weather will be related to the anchoring low-pressure system in the Pacific basin. On Saturday, that low will start to swing into British Columbia pushing that ridge into Central Canada and possibly producing some moderate to severe thunderstorms across B.C. and areas north of Edmonton. Calgary is not expecting any active weather on Sunday; however temperatures will drop rapidly as that cold front crosses the Rockies. Stronger north wind is expected late Saturday, and by Sunday the daytime high in Calgary will peak 22 C compared to 33 C on Saturday. Currently Calgary does not meet the threshold criteria for a heat warning, but that does not mean these temperatures should be taken lightly. Homes without air conditioning will still be quite warm with overnight lows in Calgary sitting around 14 C to 15 C for the next few nights. People and animals are encouraged to try to stay hydrated and to take breaks from the heat throughout the day to help alleviate some of the additional health-related stresses associated with periods of unusual warmth. The end of the weekend will be cooler with highs in Calgary slightly below the seasonal average of 24 C and lows closer to 10 C (which is normal for this time of year).
