Clinton Journal | State climatologist: December 2021 was unusually hot
CHAMPAGNE – Preliminary data shows that December was among the 5 hottest on record in Illinois, with no snow on Christmas, according to Illinois state climatologist Trent Ford of the Illinois State Water Survey. University of Illinois. The exact ranking for December 2021 will be confirmed later this month.
The statewide average temperature in December was 39.4 degrees, 9.6 degrees above the 1991-2020 average. This December was the hottest month on record in Carbondale, the second hottest on record in Quincy, the third hottest on record in St. Louis, Springfield and Peoria, the fourth hottest in Rockford and Champaign-Urbana, and the fifth hottest in Chicago.
Average December temperatures ranged from a low of 30 in northern Illinois to a high of 40 in southern Illinois, between 6 and 12 degrees above normal. High temperatures have regularly reached the 70s last month in southern Illinois, including a high of 78 degrees in Randolph County on Dec. 4. Carbondale recorded 74 degrees on December 25, one of the hottest Christmas temperatures on record in the state.
Total precipitation for December ranged from about 1 inch in far western Illinois to nearly 6 inches in far southeastern Illinois. Most of western Illinois was 0.50 to 1.5 inches drier than normal, while eastern and southern Illinois were nearly 0.50 inches wetter than normal. normal for the month.
Snowfall was 1 to 8 inches below normal in December. Snow totals ranged from 4 inches in extreme northwestern Illinois to 0 inches south of Interstate 72.
Many places only recorded their first measurable snowfall in the last week of the month. Chicago recorded its first measurable snowfall of the season on December 28, eight days later than the last previously recorded first snowfall.
With the liquid water content of snow and precipitation taken together, the preliminary statewide average total precipitation in December was 2.70 inches, 0.02 inches above the 1991-2020 average. .
Extreme weather conditions, including tornadoes, hail, and strong winds, tend to be most common in Illinois between April and June. However, unlike Atlantic hurricanes or extreme cold, Illinois does not have a “tornado season” because tornadoes and other severe weather can occur and do occur year round in the state. .
The most notable event took place on the night of December 10, when severe thunderstorms moved through the southern Midwest and south central, causing multiple very strong tornadoes in Illinois, Missouri, Arkansas, Tennessee and Kentucky. The tornado outbreak has left dozens of people dead in the region, including six dead in Illinois, many injured and thousands of homes and structures damaged or destroyed.
Overall, the NOAA Storm Prediction Center presents nine Illinois tornado reports for December, compared with an Illinois average of just over one December tornado per year between 1950 and 2020.
The short and long term outlook indicates the potential for actual winter conditions in the Midwest. The Climate Prediction Center’s 8- to 14-day forecast shows high probabilities of below normal temperatures statewide for the second week of January, with higher probabilities of drier-than-normal weather during the same. period.
Meanwhile, the outlook for the whole of January shows the highest likelihood of near or below normal temperatures and above normal precipitation, still reflecting some of the weakening La Niña pattern in the Pacific. .