Drab, Dreary & Dull Forecast
Fog The Biggest Issue
Another grey start today with a few possible peeks of sun this afternoon then more fog settles in tonight. There will be some freezing fog forming too tonight. That is when fog develops when the surface temperature is at or below freezing.
You may have noticed a beautiful byproduct of fog and surface temperatures below freezing yesterday. Those were the conditions Sunday night into Monday. This produced some freezing fog. The icy spikes protruding off this branch are an example of rime ice. It forms when supercooled water freezes onto surfaces. Supercooled means it is water, or in this case fog or small cloud droplets, that is below freezing but hasn't frozen yet. The objects where fog freezes onto have to be at 32° or colder. The picture is from a walk I took with my dog early Monday morning.
Today should be the 11th straight day with temperatures above average. January is running about 4.8° above average. The average high for this date is 31°. Our highs today should reach into the lower to middle 30s.
We will drop back closer to average by the end of the weekend but nothing brutally cold in the forecast for the next several days.
Snowfall Deficit Here
Seems like heavier snow has been falling all around us this winter with a growing deficit in snowfall centered over the Chicago area. We have actually had a more active pattern lately with snowfall reported on five of the last nine days at O'Hare. The total during that period was 4.3". So far this winter we have seen 4.5" of snow which is less than half of normal to date. We should have 9.5" by now.
The GFS model only squeezes out a little snow over the next two weeks. Most of that would be in the form of some lake effect snow this Thursday. It suggests a grand total of about an inch and a half near the city and southward when all the snow is added up between now and January 20th.
The European model is even more stingy with snow. It spits out under a half inch in total through a week from Wednesday.
The growing snowfall deficit is even more dramatic when looking at a national perspective.
The European model total snowfall accumulation forecast through the next ten days shows what looks like a big hole on the map over Illinois and Indiana.
Staying Above Average
The longer range temperature probabilities forecasts still have us outlooked for above average temperatures overall but like yesterday, the signal isn't strong. The long range models continue to favor us for above average temperatures just past the middle of January. The 6-10 day temperature probability forecast has Chicago and areas north and west of here outlooked for above average temperatures overall from January 10th through January 14th. Chicago again is in the lower end of the probabilities. Similar pattern for the longer range 8-14 day forecast. It continues to favor us for above average temperatures overall during the period from January 12th through January 18th too but with the lowest range of probability.
Dry Long Range Signal
The longer range precipitation probabilities forecasts has us outlooked for an overall dry pattern during the middle of this month. The 6-10 day forecast from January 10th through January 14th has us outlooked for below average precipitation. The 8-14 day forecast has us near normal in northern Illinois for precipitation from January 12th through the 18th with the rest of Illinois and Indiana outlooked above average overall.
Looking Even Longer Range
The experimental multi-model ensemble temperature probability forecast keeps the relatively mild pattern coming through the end of the month. Not only is the Midwest favored for above average temperatures overall from January 16th through the 29th but most of the country is outlooked to be above average (lower left image). Not much of a signal regarding the precipitation outlook for the same period (lower right image). The forecast calls for equal chances of being above or below average with precipitation.
A Look Back At Last Year
Did 2020 feel warm to you? It should have. It was the 5th warmest year on record for Chicago with an average temperature of 53.3°. Snowfall was fairly scarce last year too. We ended up with 28" total which is more than 8" below average for the year.
Here is my 7 day forecast:
Today: Patchy fog early then mostly cloudy, peeks of sun pm High: 35
Wednesday: A.M. patchy freezing fog, mostly cloudy Low: 25 High: 36
Thursday: Mostly cloudy, a few flurries possible Low: 30 High: 37
Friday: Mostly cloudy Low: 28 High: 36
Saturday: Mostly cloudy Low: 25 High: 35
Sunday: Mostly cloudy Low: 24 High: 34
Monday: Mostly cloudy Low: 23 High: 35