Today through Friday-
The weather coming up will feel more “normal” for December rather than February. We’re on track for a frigid week this week as a very strong ridge has developed just to our north/northwest resulting in very cold air being pulled southwest into the Inland Northwest from Canada. The current deep snow pack, especially thanks to Sunday’s/Monday’s storm over performing, will help set the stage for the frigid conditions. Most locations have between 8-17″ of snow currently which is more than enough for temperatures to turn very cold. For those of you wondering how deep snow pack can have big affects on temperatures, snow is made up of ice crystals which reflect the incoming solar radiation from the sun back into space. As a result, temperatures don’t warm much during the day despite lots of sunshine. During the night, temperatures drop quickly as the snow pack produces radiational cooling, which is due to the top layer of snow evaporating and causing the temperature to fall closer to the dew point.
Anyhow, back to the forecast, we’re looking at temperatures in the lower-mid 10s each day through Friday possibly. Given how cold the air is though coming down from Canada and the added help with the current snow pack, I wouldn’t be surprised to see some locations only recover to around 5 degrees during the day. At night, widespread lower-mid 0s are just about certain. Many places though have a shot at a low in the -5 to -15 degree range. Either way you look at it, it will be BITTERLY COLD!
Finally, the last thing to mention is the wind potential for today into tomorrow. We could see winds of 15-25mph thanks to this ridge, resulting in wind chills in the -10 to -25 degree range. The coldest weather is expected at night so caution is advised if outside during the night.
Saturday through Tuesday-
The ridge to the north will greatly weaken and shift further north, taking the frigid weather along with it. Meanwhile, the jet stream will become positioned to bring storms from west to east into the Pacific Northwest starting some time Saturday. From Saturday onward it looks like several storms will impact the Inland Northwest with little or no break inbetween storms. Increasing moisture riding over the colder air at the surface will result in widespread snow for all elevations. It’s looking increasingly likely that a prolonged snow event is on the way starting Saturday night and persisting through maybe Tuesday for most of the Inland Northwest. The models suggest heavy amounts of snow will be possible. Earlier ideas suggested maybe some rain mixing in by Monday and Tuesday, but the latest models have discarded that idea. Instead, it’s looking like temperatures will warm to around freezing but will remain just below the 32 degree mark. Since it’s February now, the best chances for snow accumulation will be at night as the higher sun angle will make daytime accumulations difficult on the roads and non snow covered surfaces. This period will continue to be watched closely in the coming days. Temperatures will be in the lower-mid 20s Saturday, mid-upper 20s Sunday, and upper 20s-lower 30s Monday/Tuesday.
The models remain in surprisingly good agreement with a good portion of this month continuing to look quite snowy.