Up to 50 mm of rain possible in central Alberta by the weekend

Cool and wet weather will impact central and southern Alberta over the next few days with a largely unstable atmosphere.

A lee low (a low pressure system that forms on the leeward or downwind side of a mountain chain) will be the main weather maker for the region for the end of the week.

The counter-clockwise rotation of the low will push moisture back toward the foothills Thursday, Friday and Saturday and could produce as much as 50 milimetres of rain.

Colder air will dominate on Thursday with daytime highs throughout southern Alberta dropping to their lowest point of the next week.

In Calgary, the overnight lows will remain just slightly warmer than average, but in the higher elevations the lows are likely to get closer to 0 C, so some precipitation there could fall as snow.

Rainfall totals are expected to range from 15 to 20 milmetres from Wednesday through Friday.

More temperate conditions will return on Friday, including sunshine and a westerly flow, and daytime highs in Calgary should reach a seasonal 18 C by Sunday.