This weekend included a lot of melting across Calgary with daytime highs climbing from 4 C on Friday to 19 C by Sunday. The start of this week will also be warm with daytime highs across most of the province sitting well above seasonal. Typical of spring, this warmth will be short-lived as a cooler air mass starts to track south and east along the foothills on Tuesday where it will be enhanced by some Pacific moisture. A couple of low-pressure systems forecast to ride south of the international border will serve as a steering mechanism and trap that moisture against the southern foothills. Rain is possible in Calgary on Tuesday night and Wednesday, before potentially turning to snow or a rain/snow mix. Accumulations should be minimal around Calgary, but with this being one of those “upsloping” situations (counter-clockwise rotation around a low situated east of the mountains) there is the potential for those totals to be either higher or lower since these synoptic setups make pinpointing accumulations very difficult. Daytime highs will be supressed by the end of the week, peaking at just 4 C on Thursday and 3 C on Friday, compared to the normal high in Calgary, which is 13 C at that time of year. Overnight lows will sit above freezing to start the week before ranging from -1 C to -4 C until early next week. The normal low in Calgary this time of year is -1 C.
