If you have been regularly checking out the weather models over the last couple of weeks you would have noticed they have been having a hard time nailing things down. One model run shows a large storm system, then 12 hours later the next model run has no storm system at all; two days later the storm system is back, but in a slightly different place. It makes for tough forecasting, but besides that, it also usually means our weather pattern is going to make a big change, and that is exactly what we are going to see in this forecast period.
The potential storm system that was originally forecast to slide to our south on Tuesday or Wednesday of this week moved in a little earlier and was a little farther north. This brought some significant snowfall to some areas, along with strong winds and blowing snow. This low, along with a building ridge of high pressure along the West Coast, is going to shift our mild weather pattern toward a more seasonable one.
With the sharp ridge to our west and a deep trough developing over eastern North America, the flow across our region will be predominantly out of the north. This will allow for much colder air to work into our region. Within this northerly flow there will be several weak systems sliding southward, bringing with them occasional clouds along with some light flurries. Each of these weak systems will be quickly followed by an area of arctic high pressure that will bring clear skies and seasonably cold temperatures. Expect daytime highs on most days to be in the -8 to -12 C range with overnight lows in the -18 to -20 C range. The coldest weather looks to move in early next week, with the weather models predicting overnight lows around -25 C.
Looking further ahead there are signs that warm air will begin to push back into our region from the west late next week.
Usual temperature range for this period: Highs: -16 to -1 C; lows, -26 to -10 C.