High levels of particulate from wildfire smoke prompted air quality warnings across British Columbia, the Northwest Territories and portions of Alberta on Friday. Areas closest to the source fires in B.C. and the Northwest Territories were measuring the highest levels of particulate with smoke drifting east and south into Alberta. As of 8 a.m. Friday, thick wildfire smoke was visible on many Drive B.C. cameras, including near Cache Creek, Lytton, Vernon and Merritt. Calgary was not placed under the air quality warnings, and as of 6 a.m. Friday, the air quality health index ratings in the city was a two (low risk) but expected to rise during the day. Cooler daytime highs on Thursday helped to lower the wildfire risk for southern Alberta and Saskatchewan, with many areas that were under an extreme risk Thursday downgraded to a very high risk by Friday. On Friday, the daytime highs across southern Alberta are expected to reach the mid-20s to low-30s, and hit the low to mid-30s again in southern B.C. A ridge of high pressure that has been driving the recent hot and dry weather conditions across central and southern British Columbia and Alberta will start to flatten out over the coming days, allowing cooler air to funnel in. This clash between the air masses is likely to create some localized instability. Strong wind is possible in the B.C. interior over the weekend, but rain is unlikely there for at least the next few days. The heat, lower humidity levels, and lack of rain will enhance fire risk in vulnerable areas with dry lightning potentially triggering new fires. Scattered showers and/or thunderstorms are expected to form on the leeward side of the Rockies Friday and travel east to west – mainly along the QEII corridor. This precipitation will continue until the middle of next week – but will not be steady and/or persistent. Isolated pockets of rain will remain largely unorganized, with some communities remaining dry with other areas may record brief periods of heavy rain with accumulations between 10 to 15 millimetres per rain event. Daytime highs in Calgary are expected to steadily drop to below seasonal values by the middle of next week, sitting around 17 C to 19 C, compared to the average high of 24 C. Overnight lows will remain at or above normal during that same period (ranging from 10 C to 13 C). The average low in Calgary this time of year is 10 C.
