Rainfall warnings issued with up to 50 mm possible west of Calgary

CTV News

6 days ago

Rainy and cooler for Tuesday. Jodi Hughes has a look at the five-day forecast from the Sky Watch Weather Centre.
A long-duration rain event over Calgary and area prompted Environment and Climate Change Canada (ECCC) to issue a rainfall warning Monday night.
In the initial advisory, the national weather agency explained some communities – especially west of Calgary – could see as much as 50 millimetres of rain before Tuesday night.
In their updated advisory Tuesday morning ECCC noted, 'Heavy rain will continue today,' and, 'Localized flooding in low-lying areas is possible.'
Rainfall warnings issued with up to 50 mm possible west of Calgary
Rainfall warnings (green). air quality warnings (purple), and air quality statements (opaque gray), on July 22, 2025.
As anticipated two different moisture-laden systems have merged over the Calgary area – one from the northwest and one from the south.
Initially, they appeared parked along the foothills west of Calgary producing isolated pockets of heavy rain Monday night before becoming a large, slow-moving system that spread north and south of Calgary, and east of the QEII and Highway 2.
Rainfall warnings issued with up to 50 mm possible west of Calgary
This amount of rain over such a short duration would create a challenge even with drier surfaces, but this rain event is the second in less than a week, meaning this rain is falling over saturated ground.
From Thursday through Sunday the Calgary area recorded a significant amount of precipitation with some communities measuring over 60 millimetres of rain while the official ECCC weather station at YYC International Airport measured just over 50 millimetres.
The rain is expected to gradually ease throughout the afternoon Tuesday and the rainfall warnings should be lifted then.
Even without the rain, Tuesday will be unpleasant with strong north winds and daytime highs in southern Alberta expected to peak in the low double-digits.
Rainfall warnings issued with up to 50 mm possible west of Calgary
Calgary will experience sustained north winds of 15 to 20 km/h for the first half of Tuesday with gusts closer to 30 to 40 km/h.
That north wind is also pushing wildfire smoke into the southeast corner of the province, resulting in an air quality statement to be issued from ECCC.
The air quality will likely deteriorate in the Calgary area once that rain moves out with smoky conditions possible around the supper hour.
Rainfall warnings issued with up to 50 mm possible west of Calgary
A strong ridge of high pressure from the Pacific basin will move across B.C. Tuesday before heading into Alberta Wednesday, kicking off a more seasonal and stable pattern for the middle of the week.
Wednesday's daytime highs in southern Alberta will sit in the low 20s with highs in the high 20s to 30 C for Thursday.