Forecast confidence remains high on an arctic outbreak early next week. For the past several days, long range forecast models have been very consistent on bringing down the coldest airmass yet this season as a result of a polar vortex collapse. According to forecast models, below normal temperatures will be present across the eastern two-thirds of the nation. The epicenter of the coldest air will fall across the northern Plains, Great Lakes, and Northeast regions. Some locations in these regions could see temperatures on the order of 2 standard deviations below normal.
It's an outbreak that will bring undoubtedly the coldest airmass of the season and the coldest airmass seen around here in 2 years (since February 9-10, 2011). Sunday through Wednesday is the timeframe for this event to occur here in Chicago. During this timeframe high temperatures will struggle to make it out of the teens if at all. Low temps will fall in the single digits with wind chill values ranging 10 to 30 degrees below zero. In addition to the cold airmass is the possibility of accumulating snowfall Saturday night through Monday.
Similar to the impending arctic outbreak, weather models also have been consistent with the chances of snow developing along the arctic front or at the onset of this arctic outbreak. Associated with this arctic front at the onset of this arctic outbreak will be a strong north-northwest flow pattern aloft that will guide these snow systems from Canada. These snow systems will come with limited moisture so not expecting much in terms of accumulation (anywhere from a dusting to 2 inches). It's worth noting that this is not all set in stone as we are still several days away. The chance for snow and how much falls still depends on the strength and/or how deep this cold airmass reaches into the Lower 48. Stay tuned for more updates!
Wednesday: Mostly sunny and unseasonably warm. Chance for flurries late. Highs in the upper 30s. Winds southwest 10-20 mph.
Thursday: Partly cloudy and cooler. Highs in the upper 20s. Winds northwest 5-15 mph.
Friday: Partly cloudy and warmer. Highs in the upper 30s to lower 40s. Winds southwest 10-20 mph.
Saturday: Partly cloudy and unseasonably warm. Chance for light snow at night. Highs in the upper 30s to lower 40s. Winds southwest 5-15 mph.
Sunday: Partly cloudy and sharply cooler. Chance for snow showers. Highs in the upper teens to lower 20s. Winds northwest 5-15 mph.
Monday: Partly cloudy and unseasonably cold. Chance for snow showers. Highs in the mid teens. Winds west-northwest 5-15 mph.
Tuesday: Mostly sunny and cold. Highs in the mid to upper teens. Winds west-northwest 5-15 mph.
8-15 day temperature trend outlook
Wednesday Jan. 23: Highs in the 30s.
Thursday Jan. 24: Highs in the 40s.
Friday Jan. 25: Highs in the 30s.
Saturday Jan. 26: Highs in the 30s/40s.
Sunday Jan. 27: Highs in the 30s.
Monday Jan. 28: Highs in the 30s.
Tuesday Jan. 29: Highs in the 30s.
Wednesday Jan. 30: Highs in the 30s.
Thursday Jan. 31: Highs in the 30s.
Be sure to check out my National Environmental News page for weather/climate related content and other environmental news.
Click on the "Subscribe" button above and enter your e-mail address to receive a free alert to our inbox when a new article is published by the Chicago Weather Examiner. Follow us on Twitter! Become a fan of the Facebook page!