By Justin Poublon
January 12, 2018 - 4:30 PM CST | 16 0
Below average temperatures will be the main story this weekend. A clipper system will move through Sunday night into Monday producing widespread snow.
I mentioned earlier this week that it will be cold, but not as cold as the last arctic episode.
Tonight it will get pretty cold. Windchills approaching -20F to -30F. A Wind Chill Advisory has been issued.
Actual temperatures will be lower Saturday into Saturday night, but with less wind the wind chills are not as chill. It will be relatively warmer south and colder northwest. By Sunday night increasing clouds and approaching snow will hold temperatures up.
Minor accumulations of 1-3" are expected statewide Sunday night into Monday. Locally higher amounts will be possible in eastern Wisconsin as flow turns northeasterly on Monday. This could lead to lake effect or enhancement and a backdoor cold front into Monday night. I'm actually preparing for 3-5" range in east-central Wisconsin. I'm waiting for details to solidify since we are still a few days away. The snow growth region is deep and forcing broad, a little more focused in the east. If more persistent banding pushes inland (beyond what is forecast), 3-5" will not be enough. I bring it up because lake effect is a touchy subject. It can lead to epicly busted forecasts in January. I'll conclude by saying that Monday could be more interesting than advertised.
Following a fresh snow cover, another arctic high will drop south across the plains during the early half of next week leading to another dip again temperatures. Models forecasting single digit high temperatures on Tuesday and a pretty cold night again. The arctic high will bring below average temperatures to eastern half of the United States but doesn't appear to cut as deeply as the last.
Return flow will begin later next week. The extended forecast is stormy as troughiness develops across the west coast. The question remains what form of "stormy", the snowy or rainy kind? The highly amplified upper level flow progged for 240hrs leads me to guess more rainy to start. The tendency towards trough in the east makes me skeptical. We'll see how it goes. Current long range simulations at the very least bring the storm track through the great lakes.