"Based on preliminary data, temperatures of 54.0°F statewide (1.8°F above 30-year normals) made 2006 the 9th warmest year in Illinoissince 1895. This was largely the result of a record-setting January last year with an average temperature of 37.9°F, 13.3°F above normal," said State Climatologist Jim Angel of the Illinois State Water Survey (http://www.sws.uiuc.edu), a division of the Illinois Department of Natural Resources.
"Similar annual average temperatures in recent years occurred in 1998 (55.0°F, 3rd warmest), 1987 (53.8°F, 12th warmest), 2005 (53.8°F, 13th warmest), and 1991 (53.7°F, 14th warmest). Top ranked years remain 1921 with 55.6°F and 1931 with 55.3°F," said Angel.
It was the 15th warmest December on record with temperatures 5.4°F above normal. Temperatures the first 9 days were 13 degrees below normal and then 12.9 degrees above normal the last 22 days. December temperature extremes ranged from -7°F at Dixon, Rochelle, and Havana on December 8 to 69°F at Grayville on December 18.
Statewide precipitation for 2006 was 41.11 inches, 2.32 inches or 6 percent above normal. While most of the state was wetter than normal last year, areas around Quincy and east of St. Louis were drier than normal. December precipitation, the 13th wettest December on record, averaged 3.67 inches, 0.98 inches or 37 percent above normal. Claremont reported 2.93 inches, the largest one-day rainfall on December 1, and Grand Chain Dam reported 7.12 inches, the largest monthly total. Other than snowfall from the November 30–December 1 winter storm, which received wide press coverage, no other significant snowfall was reported in Illinois during December.
The National Weather Service outlook for January–March calls for temperatures above normal and precipitation below normal across Illinois. That forecast is driven largely by a moderate El Niño event now present in the Pacific Ocean but expected to diminish gradually in the next few months.
"Even so, we can still expect periods with temperatures and precipitation more typical of the winter season," concludes Angel.