The last long weekend of the summer will be cool and wet for much of southern Alberta. As of 5 p.m. Friday, the high for Calgary was a cool 15 C, but there is still the potential for the city to gain a couple of degrees over the next few hours to get closer to that forecast high of 19 C, which would be seasonal. However, by Saturday, highs in the upper teens will be the best many communities will be able to achieve as a low-pressure system sends waves of wet weather our way, preventing the sun from being able to warm up the surface. The low is positioned over the northwest U.S., scooping up water vapour from the Pacific Ocean and moving it up into Alberta. We already experienced light showers and thick, low-lying clouds associated with the outer edges of this system throughout Friday afternoon in the city, and northerly winds from another colder low positioned over northwest Alberta. By late Saturday morning, scattered showers are likely for Calgary, but the main wet weather event will take place throughout Sunday and into Monday, where rainfall totals could range between 15 and 25 mm over 24 hours. Models have this low on the move on Tuesday, which will allow high pressure to start to work its way back into the province. This will result in sunshine on Wednesday and some warm temperatures in the low 20s. The long range brings more optimism on the temperature front, but on-and-off showers could be a recurring pattern for the first few weeks of September.
