The weather models kind of got their act together for last issue’s forecast. They correctly predicted the warm air that moved in around November 4 but were a little off as the warm temperatures stuck around longer than expected. This then translated into a shift forward in time for the remainder of the forecast.
In this forecast period there is some uncertainty, but the weather models have gone from dramatically changing the forecast every 12 hours or so, to slowly changing things over 48 to 72 hours. So, with my long lead time on the forecast, I am keeping my fingers crossed that the models are starting to figure things out.
Read Also
Thunderstorms and straight-line winds
Straight-line winds in thunderstorms can cause as much damage as a tornado and are next on our weather school list exploring how and why severe summer weather forms.
To start us off, the models are showing an area of low pressure developing over the north-central U.S. on Wednesday and then deepening as it moves over the Great Lakes. Currently it looks like most of the precipitation from this low will stay to our south and east, but at this time of the year we always have to be a little concerned with these systems. Colder air will work southwards on the back side of this low on Friday and Saturday, with daytime highs expected to be around -3 C with overnight lows falling to around -10 C.
Late in the weekend, the weather models are showing another area of low pressure dropping southeastwards out of northern Alberta. This low could bring a quick shot of snow, with amounts ranging from a dusting to maybe a couple of centimetres. Temperatures will moderate a little bit ahead of the low, with daytime highs around the 0° mark and overnight lows falling to around -7 C.
To start the week of November 8, the weather models are showing a third area of low pressure developing to our southwest and then tracking eastwards across the north-central U.S. from Tuesday to Thursday. Once again it looks like most of the precipitation will fall to our south, but a small shift northward, or an increase in the intensity of this low, could result in measurable snow falling across southern regions.
Temperatures will remain seasonably mild ahead of this low, with daytime highs around 0° and overnight lows remaining in the -7 C range.
Usual temperature range for this period: highs -6 to 6 C, lows -15 to -2 C. Probability of precipitation falling as snow: 75 per cent.
