January in Illinois – warm, wet, foggy, but little snow

Based on what we have seen so far in January, Illinois has been warmer and wetter than normal with little snowfall.

The statewide average temperature is 27.9 degrees, 3.9 degrees above normal. The statewide average precipitation (rain plus the water content of snow) is 1.6 inches, 0.4 inches above normal.

Snowfall has been light across Illinois. In fact, the Midwest has been very quiet so far this month with below-normal snowfall everywhere except for MN and the northern half of WI (map below). Northern Illinois, which is normally the snowiest spot in the state, is down 5 to 10 inches for the month so far. It has been a relatively quiet month with few storm systems and the precipitation we have gotten has more likely fallen as rain (or freezing rain) instead of snow. Of course, it’s tough to get snow when you are almost 4 degrees above normal.


The other notable features of January have been the prevalence of thunderstorms, fog, and overcast days. Thunderstorms in January are somewhat rare, but can occur when we have warmer stretches of weather.

So far in January, Chicago O’Hare airport has reported 2 days with thunder, and 14 days with fog. In the 19 full days in January, they had 3 clear days, 6 partly cloudy days, and 10 cloudy days. On average, Chicago sees about 2 days with fog in January and reports of thunder about once every other year.

Other reports of fog for January in Illinois include Rockford with 13 days, Peoria with 14 days, Quincy with 15 days, Champaign with 16 days, Springfield with 15 days, Bloomington with 12 days, and Carbondale with 12 days.

Latest Monthly and Season Outlook for Illinois

The NWS Climate Prediction Center released their latest outlooks for February and upcoming seasons. So far, Illinois has been warm and wet in January. The statewide average temperature is 3.5 degrees above normal. Statewide precipitation is at 1.6 inches, 0.5 inches above normal. The rest of January looks like more of the same weather.


Illinois has equal chances (EC) of above, below, and near-normal temperature in February. Illinois has an increased chance of wetter than normal conditions in February. Click to enlarge.


Illinois has EC for temperatures and an increased chance of above-normal precipitation for February through April. Continue reading

Cold, Dry December Ends a Warm Year in Illinois

A cold, dry December wrapped up a warm year in Illinois.


The statewide average temperature for December was 28.6 degrees, 1.3 degrees below normal. The statewide average precipitation was 1.41 inches, 1.28 inches below normal.

December precipitation was light and below normal across most of Illinois, except for far southern Illinois. The largest reported precipitation total was 6.03 inches in Rosiclare, an NWS-COOP site in Hardin County. Precipitation includes rainfall and the water content of snow. Click on the images to enlarge.

December snowfall was absent in far southern Illinois and increased northward. Only northern Illinois received above-normal snowfall. The largest monthly snowfall total was 24.3 inches in Bull Valley, a CoCoRaHS station (IL-MCH-13) in McHenry County.

Annual – 2016

Continue reading

Cold, Snowy First Half of December

The statewide average temperature for the first half of December is 27.9 degrees, 4.7 degrees above normal. Snowfall (maps below) has been heaviest north of Interstate 80, ranging from 10 to 15 in many locations. The snowfall totals taper off southward, dropping to about 2 inches near Interstate 72, and down to zero inches near Interstate 70 and sites to the south. For many areas in northern Illinois, this represents above-normal snowfall.

More wintery weather is expected today and tomorrow as another winter storm moves through the Midwest. This will be followed by very cold temperatures on Sunday and Monday before moderating somewhat on Tuesday.


Latest Round of Snowfall in Illinois

Just a quick note showing how the recent winter storm played out. The snow was widespread across the upper Midwest, including northern Illinois. Amounts of 5 to 10 inches were common in northeast Illinois. Two sites in McHenry County had over 10 inches of snow: Harvard (IL-MCH-66) with 11.7 inches and Bull Valley (IL-MCH-13) with 10.8 inches. Central and southern Illinois were warmer and received mostly rain instead of snow. Rainfall amount in southern Illinois were in the neighborhood of 0.5 to 0.75 inches.



New Outlook for December – Wetter, Colder in Illinois

The NWS released their latest outlook for December. They have Illinois with equal chances (EC) of above, below, and near-normal temperatures for the entire month. However, the day to day forecasts out to 14 days show Illinois having colder than normal temperatures on most of the days. The NWS product for weeks 3 and 4 suggest that warmer-than-normal weather will return in the second half of December. In general, I have higher confidence in the forecasts out to 14 days.

The December outlook also shows Illinois with an increased chance of being wetter than normal. This is true in the shorter range forecasts out to 14 days as well. Considering it’s December, a forecast of colder and wetter than normal conditions sure sounds like a recipe for snow. As you may recall, last December was notable for having almost no snow.

Click to enlarge.