We Are Due For Some Real Snow
A Few Flurries Or Light Snow Showers Today
Where is winter? December is running 5.3° above average so far. We have seen just a trace of snow on four days so far this month. We are 4.5" below average in terms of snowfall for the season so far and down 3.8" for December. It's been almost three years since a storm has produced six inches of snow or more in a single day at O'Hare. The last storm to do that hit on February 9th, 2018 when 6.2" fell. This December would tie with several other years as the 5th least snowiest in 134 years of records if we fail to get any more snow beyond a trace.
More on our winter that hasn't been all that miserable yet and chances for sticking snow below.
Look for highs today again about average in the lower to middle 30s. This will be the coldest day of the next seven.
I mentioned in yesterday's post by Chicago winter standards, this one has been a piece of cake so far. The Midwest Regional Climate Center has an index called the Accumulated Winter Season Severity Index to keep track of how severe the winter is for cities around the country. It is sometimes referred to as the "misery index". It uses categories like mild, moderate, average, severe and extreme to describe the collective misery of the winter. I updated it below but nothing has changed. So far Chicago is still in the "mild" category, the least severe of all the categories.
Most of the Midwest has seen a relatively easy winter to this point. The only city on this map that has anything worse than an "average" ranking is Duluth, Minnesota. They have seen a "severe" winter so far. Even Duluth is well below average in terms of snowfall. So far this season they are down seven inches compared to average.
The forecast for temperatures the next several days will not put our "mild" ranking in jeopardy. About average today then most of the next seven days will see highs around or above 40°. We even flirt with 50° next Wednesday. Models are hinting at a dramatic drop by Christmas Eve with highs maybe only in the 20s and they keep it that cold right through Christmas day too.
Several Weak Systems
Our pattern will be more active over the next ten days but none of the systems appear to be very strong. At least none offer that much in the way of sticking snow. We may see a few lake effect flurries or light snow showers near the lakeshore today. The GFS model has some rain developing late Friday night or early Saturday morning that will continue well into Saturday. It may initially mix with some light snow but it will be mainly light rain falling on Saturday. Next up is a system late next Wednesday starting as rain and then changing over to some light snow by early Christmas Eve. More on the amounts expected with that system below.
The models have a range of just a few tenths of an inch of snow to nearly three inches with Saturday's system. Most models are on the low end of that range and I think snowfall amounts will be rather light if any with this system. Models squeeze out similar snowfall amounts with next week's system. This far out my best guess is maybe a half inch to an inch late next Wednesday into early Christmas Eve day.
White Christmas Watch 2020
The outlook for a white Christmas this year still isn't that great but we will have to watch next week's system closely.
The latest GFS model forecast for snowfall accumulation through Christmas day does offer hope for an inch of snow in total or a bit more from south of the city into northern Indiana. Most of us though would get a dusting or a few tenths of an inch at most.
The European model again offers similar snowfall amounts but distributes it differently. It suggests just under an inch in Chicago and more than an inch in northern Indiana but most of us would see just a few tenths of an inch in total between now and Christmas day.
Next week's system is still about a week away and that can be an eternity in terms of snowfall forecasts so stay tuned. A lot can change and probably will between now and then.
Mild End To Month For Most Of The Country
The longer range temperature probabilities forecasts have us mainly outlooked for above average temperatures overall for the end of December. The 6-10 day temperature probability forecast has us above average overall through the day after Christmas. It covers the period from December 22nd through December 26th. The longer range 8-14 day forecast has us outlooked for about average temperatures overall from December 24th through the 30th. Just a reminder-this doesn't rule out a couple of days cold enough for some snow but it suggests most days during this period will be above average. The models have been hinting at the coldest air of the season so far arriving just in time for Christmas Eve and Christmas day. Those colder days would be the exception though to the relatively "mild" rule for the longer range temperature forecasts.
Longer Range Outlook Still Dry
The longer range precipitation forecasts has an expanding area of the country with fairly high probabilities of below average precipitation for the end of the month. The 6-10 day forecast from December 22nd through December 26th has us outlooked for below average precipitation overall. The 8-14 day forecast from December 24th through December 30th also has us outlooked for below average precipitation overall.
Here is my 7 day forecast:
Today: Cloudy, light snow or flurries at times near the lakeshore High: 35
Friday: Partly to mostly cloudy Low: 26 High: 41
Saturday: Cloudy, light rain or snow possible early then light rain Low: 33 High: 40
Sunday: Partly to mostly sunny Low: 28 High: 40
Monday: Partly to mostly sunny Low: 31 High: 43
Tuesday: Partly to mostly sunny Low: 34 High: 44
Wednesday: Partly to mostly sunny Low: 35 High: 46