Wednesday, March 14, 2012

Fog and (snow) showers

2pm Update: Cool air remains entrenched in the St. Lawrence Valley today with temperatures no better than plus 1 or 2C in Montreal. We also had several hours of wet snow over the city. This while places in southern Ontario from the GTA west towards Windsor are approaching 15 to 20C this afternoon. Even Ottawa is at 7C. It will warm up here by the weekend (fingers crossed). The snow today melted on contact and is now just bout over. 

An upper level low pressure area will slide across eastern Ontario today and into southwestern Quebec. The low will keep cold air trapped at the surface in the St. Lawrence Valley, meaning the warm temperatures that avoided the city yesterday will do so again today. Montreal has dense fog at 7am and a lonely 1C, where we have been stuck since 10pm last evening. We will have a little more company today however as temperatures will be down across eastern Ontario as well. Sowers are occurring also with the system and will spread into Quebec from Ontario today. All Montreal could manage in the low clouds and fog yesterday was 8C, meanwhile Kemptville, ON was 17C. Areas just to the south of my location, as little as 20 minutes away warmed to 16C (60F), while the best I could do here on Ile Perrot was about 7C (45F). Today we are starting off very foggy across the region with visibilities under 1km at Dorval since 3am and as little as 1/2 kilometre at times.

The big news will be the heat during the upcoming weekend and into the start of next week. The balance of this week will be mild but rather cloudy with the risk of showers at times and even a thunderstorm late Thursday. By Saturday strong high pressure will move into the region and slowly slide off the east coast. It will pump very warm and dry air from the southwestern US that will send temperatures soaring to record highs for March. Temperatures will likely approach and exceed 20C across eastern Ontario and western Quebec by Sunday and prevail well into next week. Some locations away from water sources may even reach the mid 20's. These temperatures will be well above the average high of 2C and should easily shatter records.

No comments: