The next couple of days will be warm and calm – as most of Alberta sits under a ridge of high pressure. Daytime highs will range from 20 C on Tuesday to 24 C on Thursday, with a chance of scattered showers along the foothills on Wednesday and across southern Alberta on Thursday. On Thursday, an incoming and dominant low-pressure system will enter British Columbia and kick off at least a few days of heightened instability as well as a multi-day rain event that will prove to be problematic due to the vast amounts of rain expected to fall over a short period of time. In Calgary, temperatures will drop to 14 C on Sunday, which is seven-degrees cooler than average. Rain is expected to start falling in Calgary on Friday night and will likely last until at least Tuesday. It is still too far out to predict rainfall totals with certainty in a system like this, and it is also too early to accurately pinpoint the areas most vulnerable for heavy rainfall totals when you are dealing with a low crossing over the Rockies – however – there is evidence that places like Calgary could record between 35 to 45 millimetres of rain on Sunday. It that happens – that would be more than10 per cent of the annual precipitation for the city. According to Environment and Climate Change Canada’s normals data, Calgary typically receives 445.4 millimetres of precipitation over the course of a year, with June being the wettest month at 112.7 millimetres of precipitation on average. The rain is expected to ease up in Calgary by the middle of next week and temperatures should return to seasonal by the end of next week.
