Wind warning issued for Calgary with gusts up to 90 km/h expected

An intense low pressure system of just 986 mb situated south of Saskatchewan will be the main weather maker in central and southern Alberta Tuesday.

Moisture is being pulled up from the U.S. Plains and Gulf and moving into central and southern Alberta as it circles counter-clockwise around this low which is acting as the southwestern anchor of an Omega block.

Cold Arctic air from the high is mixing with that precipitation and limiting daytime highs to well below seasonal for much of southern Alberta.

Throughout the day Tuesday and overnight Wednesday a cooler atmospheric profile will lead to heavy wet snow in portions of southern Alberta – especially along the southern foothills. It is possible some snow might start to accumulate during the day along the Highway 2 corridor south of Calgary and west of Calgary along the Trans-Canada highway, however warmer conditions Wednesday will make this is short-lived concern.

Rainfall totals for this multi-day event could exceed 50 milimetres east of Highway 2 and the QEII Highway with Environment and Climate Change Canada (ECCC) warning some areas may see more than 100 milimetres – or the equivalent of one month’s worth of rain in under 36 hours.

While the bulk of this precipitation is forecast to fall in areas that desperately need moisture, there is the potential for pooling and/or localized flooding as the ground will be unable to absorb that much moisture in such a short period of time.

Winds will be intense throughout the day – prompting ECCC to issue wind warnings overlapping many of the rainfall warnings. In Calgary winds are expected to range from 40 to 60 kilometres per hour earlier in the day and peak at 50 to 80 kilometres per hour after noon.

Rain will be mostly steady in Calgary Tuesday as the city border the western edge of this massive system. Rainfall totals should be between 10 to 15 millimetres Tuesday with Wednesday starting to bring better conditions.

Daytime highs by Thursday will exceed the average of 15 C and likely to peak on Friday at 24 C.