Daytime highs across southern Alberta will remain in the mid- to high 20s for the next seven to 10 days. Similar to Monday, the Calgary area can expect mainly sunny conditions Tuesday with increasing wind speeds in the afternoon and evening. There is a slight chance of scattered showers and/or thunderstorms in the afternoon, mostly along the northern half of the foothills, with building cloud and heightened instability expected Wednesday. Isolated showers and thunderstorms will likely start to form in a line from west of Calgary toward the capital region Wednesday in the early afternoon, with the trailing edge potentially catching the city of Calgary as well. Once those cells make it past the QEII, there will likely be a little more organization and additional energy, so there is a chance of rapid intensification and the possibility of moderate to severe thunderstorms forming in the corridor between the Yellowhead and TransCanada highways. If this happens, large and damaging storms may form along the Alberta/Saskatchewan border by Wednesday night. There is a 30 per cent chance of heat-driven thunderstorms across the region Thursday and again on Saturday—including in Calgary—but otherwise the remainder of Stampede should be hot and dry.
