Looking back at last week’s forecast, it would seem I was way off with my forecast for widespread frost. I can’t even really say I was close, but if we look at the overall weather pattern for last week, you could actually say I was close. Thanks to a strong area of high pressure over the southeastern U.S., the same high that blocked the movement of Hurricane Florence blocked the cold arctic air, keeping it about 300 km farther north. That northward shift allowed the forecast lows to also take a more northerly track, which kept us under cloudy skies. Put it all together and it turned into a much warmer and wetter period than originally expected.
For this forecast period, it looks like we are going to slip into a weather pattern that we haven’t seen in a while. The weather models show a meridional flow developing, which means there will be a strong west-to-east movement of air across central North America. To our north there will be cool arctic high pressure, with warm high pressure building to our south. In between we’ll see areas of low pressure moving through every couple of days. It looks like we will be stuck in between these two features, meaning we’ll see a fair bit of clouds, good chances of more rainfall and relatively cool temperatures.
The first low is forecast to move through our region late on Wednesday and into Thursday. Southern regions will see the best chance for significant rain, with central regions receiving the odd shower. This low will quickly be followed by another weaker system on Friday and again on Sunday. One final area of low pressure during this forecast period is expected around Tuesday or Wednesday of next week.
Thanks to the cloudy and breezy conditions expected for much of this forecast period, we should expect to see high temperatures on most days in the 12 to 15 C range and overnight lows around 5 C. There is a chance of frost around the middle of next week, but confidence in this part of the forecast is fairly low.
Usual temperature range for this period: Highs, 12 to 22 C; lows, 1 to 10 C.