First Real Sticking Snow Of The Season
Quick Calendar Check
The average date of the first measurable snow (.1" or more) is November 17th so the arrival of this season's first real sticking snow early Tuesday is about a week late. The average date of the first 1" or greater snowfall is December 7th. If we get the expected inch or more in my forecast, it would be about about two weeks early.
We have seen a couple of days in October when a trace of snow was reported. Even though this will be the first fairly significant snow of the season it will not last long. The approaching system will initially spit out some snow late Monday night into early Tuesday but as temperatures climb on Tuesday we will see a changeover to rain from south to north. Any snow that falls early in the day will melt quickly as temperatures eventually climb well above freezing into the middle 40s.
The timing is for the snow to start early Tuesday morning around 2 to 3 AM and continue through the morning commute. At the onset there may be a mix of some sleet too and then as the morning progresses it should all change to rain from south to north. By noon Tuesday it should be primarily rain.
Here's a look at what several models are saying about the snow.
The GFS model is calling for between a half inch to an inch of accumulation.
The NAM model is suggesting between one to two inches total.
The European model says between an inch and about an inch and a half of accumulation. Snow could fall for about a three to six hour periods so some accumulation looks likely.
The accumulated snowfall meteogram shows a range of model solutions for the snow. On the low end it shows about a half inch and on the high end about two and a half inches. I'm thinking most areas will get between an inch or two and there could be a few spots that get nearly three inches mainly near the Wisconsin border. The further north you are the later the transition from rain to snow so the more the accumulation.
How much snow will we get this winter? My best guess is included in my winter forecast.
We are in the middle of a streak of four straight days with highs in the 40s. Timing is everything and the timing is good this week for a warm up just in time for Thanksgiving. Highs should climb to near or above 50° Wednesday, Thursday and Friday.
50s For A Few Days
Average highs for Thanksgiving are in the lower 40s. The GFS model shows highs right around 50° across northern Illinois and Indiana. Southwest winds along some partial sunshine should do the trick.
We aren't the only ones that should be thankful for a mild Thanksgiving. The GFS temperature anomaly forecast shows most of the country will be between 5° to 15° above average on Thursday.
Tuesday's snow won't stick around long. Temperatures climb from the lower 30s in the morning into the lower to middle 40s that afternoon.
Trending Towards Milder Temps
It's been a mild month so far. We are nearly 8° above average. The longer range outlooks for temperature are all either near normal or above. The 6-10 day temperature probability forecast still has us outlooked for about average temperatures from November 28th through December 2nd. The 8-14 day forecast favors us for above average temperatures overall from November 30th through the December 6th.
Looking even further into our future at the multi-model ensemble forecasts for temperature anomaly is no different. The week ending December 11th is outlooked to be well above average overall and the the following week falls back to about average.
Drying Out After Wednesday
After Tuesday's snow and rain there will be some showers on and off Wednesday. The GFS model then dries us out for the end of the week and all the way into early next week.
Dry Outlook For Early December
The longer range precipitation probabilities keep us drier than average from the last few days of this month into the start of the next. The 6-10 day forecast from November 28th through December 2nd has us outlooked for below average precipitation overall. The even longer range 8-14 day forecast from November 28th through December 4th continues to favor us for below average precipitation too.
Here is my 7 day forecast:
Today: Partly to mostly sunny High: 44
Tuesday: Light snow/sleet/rain early then rain (1-2 inches snowfall possible) Low: 32 High: 45
Wednesday: Cloudy, on & off showers Low: 41 High: 51
Thursday: Partly to mostly cloudy Low: 42 High: 50
Friday: Partly to mostly sunny Low: 37 High: 50
Saturday: Partly to mostly sunny Low: 36 High: 47
Sunday: Partly to mostly cloudy Low: 36 High: 46