Significant rainfall is expected early next week, with 75 to 100 mm expected by Wednesday morning.
A long duration rainfall event will impact the eastern slopes of the Rockies on Monday and Tuesday. A broad area from Hinton to Waterton is expected to see at least 50 mm by Wednesday morning, with 100 mm or more possible in some regions of the foothills. Currently it appears as though the greatest rainfall amounts will be near Kananaskis, west of Calgary.
https://weather.gc.ca/warnings/report_e.html?ab12