Friday will be the best day of the weekend with widespread sunshine and seasonal daytime highs across central and southern Alberta. It will be a different story for the capital region, where a low-pressure system west of Edmonton will track east over the next 24-hours and produce a significant amount of rain. A yellow-level rainfall warning has been issued for areas at the north end of the Rockies and east of the B.C. border. Environment and Climate Change Canada says heavy rain with totals near 50 to 60 mm is expected. “Heavy rain will begin this evening. Rain will continue through the day on Saturday and into the overnight, with isolated thunderstorms enhancing the rainfall amounts.” The national weather agency notes potential risks including water, which will likely pool on roads and in low-lying areas. “Some property damage is possible,” ECCC warned Wind speeds will pick up throughout the day with sustained southeast winds in Calgary of 20 to 40 km/h. Saturday could be a very active day of weather throughout Alberta. At the same time, that northern low is expected to gain traction around Edmonton, a second system will develop in the southern portion of the province. The combination of the two lows stacked north to south, east of the Rockies - along with their natural counterclockwise rotation and the blocking influence of a large low-pressure system situated over the eastern prairies - will enhance instability and funnel moisture into the region. Severe thunderstorm warnings will likely be issued in some areas as storm cells have the potential to develop quickly and intensify rapidly. In Calgary, wind speeds will be moderate Saturday and Sunday, and temperatures will continue to drop over the weekend. Rain is possible both Saturday and Sunday, with thunderstorms likely on Saturday. Daytime highs will return to seasonal for Calgary by the beginning of next week, and sit in the low 20s until at least next weekend.
