ABOVE NORMAL TEMP REGIME TO HOLD WITH LOTS OF CLOUDS AND A WINDY TUESDAY NIGHT/WED/THU STORM SYSTEM WITH RAIN NEXT WEEK—-BUT MODELS SUGGEST THE ARCTIC SPIGOT WILL OPEN SENDING FRIGID AIR INTO THE COUNTRY THE WEEK AFTER NEXT (ALSO THE WEEK LEADING UP TO THE CHRISTMAS HOLIDAY)

December is the Chicago area’s 2nd cloudiest month–and this December is living up to the month’s reputation. Clouds will be hard to scour from area skies this weekend in any meaningful way.  And prospects for a windy early winter storm which keeps Chicago in its comparatively mild front side could bring rain from the clouds Tuesday night and Wednesday. The system gets bogged down in an atmospheric blocking pattern in the back half of next week which means we could be dealing with the SAME SYSTEM for the majority of next week. The injection of moderately colder air later next week introduces the chance flakes of snow could mix in with its backside rain showers next Thursday and Friday

BUT IT’S THE FOLLOWING WEEK which gets downright wintry. Colder arctic air is to sweep into a huge swath of the country as a dome of abnormal winter warmth builds a giant atmospheric ridge over western North America and sends northwesterly steering winds sweeping into the country directly out of the arctic. If that forecast verifies, we’re in for a very chilly back half of December.

Current modeling has next week’s temp averaging 33-deg–which is a modest 1-deg above normal–but the following week’s (Dec 19-25) average temp plummeting to 19-deg—a 14-deg week over week decline. It that verifies, the temp change will be quite jarring!