An atmospheric combination of an upper-level trough, surface low, high atmospheric moisture, and southeasterly winds is causing heavy rainfall in parts of the Prairies, with totals exceeding 100 mm in some areas.

Soaking rains that began on Friday will persist into the weekend as a broad trough moves over the western Prairies, leading to a risk of localized flooding in Alberta and Saskatchewan. Some parts of Alberta may experience over 100 mm of precipitation by Monday morning.

As of Saturday morning, significant rainfall totals have already been recorded in Alberta:

• Calgary: 52.6 mm
• Lethbridge: 20 mm
• Longview: 49 mm
• Sundre: 74.9 mm

In addition to heavy rainfall, parts of the Rockies are also expected to see accumulating snowfall over the weekend.

The precipitation is expected to intensify on Saturday, with the heaviest rain moving east into Saskatchewan overnight Saturday and into Sunday as the trough progresses eastward.