Category: Winter

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Dry and Mild February Ends an Otherwise Cold Winter

The preliminary statewide average February temperature was 33.8 degrees, 2.8 degrees above the 1991–2020 normal, 4.6 degrees above the 20th Century average, 2.8 degrees above the most recent 30-year average, and it tied for 29th warmest February on record going back to 1895.

The preliminary statewide average total February precipitation was 0.54 inches, 1.57 inches below the 1991–2020 normal, 1.32 inches below the 20th Century average, 1.65 inches below the most recent 30-year average, and the 5th driest February on record statewide.    

Data are provisional and may change slightly over time

Mild February Temperatures with Some Cold Breaks

Most perceive February weather as consistently cold and dreary. But February often brings some of the largest day-to-day temperature swings in Illinois. Figure 1 shows daily temperature departures from normal in Pana last month. The first week of February was mainly 5 to 15 degrees cooler than normal, followed by a prolonged period of temperatures that were 5 to 25 degrees warmer than normal.

Daily average temperatures and departures from normal in Pana, Illinois.
Figure 1. Daily February average temperatures and departures in Pana.

February average temperatures ranged from the low 40s in southern Illinois to the high 20s in northern Illinois, between 1 and 7 degrees above the 1991-2020 normal (Figure 2). During the peak of extreme cold in early February, many stations across Illinois recorded nighttime low temperatures well below 0, including -8 degrees in Paris and -2 in Aurora. Meanwhile, the milder weather in mid-February brought some impressive daytime highs including 77 degrees in Cahokia Heights and 72 in Moline. The coldest place in the state last month was Stockton in Jo Daviess County with an average February temperature of 28.5 degrees, and the warmest place in the state was Crab Orchard in Williamson County with an average temperature of 41.5 degrees.

The milder weather last month broke 76 daily high maximum temperature records and 31 daily high minimum temperature records. Meanwhile, the extreme cold in early February and the third week of the month broke 2 daily low maximum temperature records and 1 daily low minimum temperature record.

Maps of February average temperature and February average temperature departures from normal.
Figure 2. Maps of (left) February average temperature and (right) February average temperature departures from normal.

Overall, the preliminary statewide average February temperature was 33.8 degrees, 2.8 degrees above the 1991–2020 normal, 4.6 degrees above the 20th Century average, 2.8 degrees above the most recent 30-year average, and it tied for 29th warmest February on record going back to 1895.

Cold Start, Mild End to Winter

Climatological winter runs from December through February and is the coldest season of the year in Illinois. Midwest winters have warmed at a much faster rate than the other three seasons over the past 100+ years because of human-caused climate change. Consequently, many of the past decade’s winter seasons have been very mild. The 2025-26 winter somewhat bucked that trend in December and certainly in January, when temperatures were 1 to 4 degrees below the 1991-2020 normals. , with December temperatures that were 1 to 6 degrees warmer than normal. However, the mild weather in mid-February pushed the meteorological winter average temperatures a bit closer to the 1991-2020 normals (Figure 3). In fact, much of the western third of the state ended winter with slightly warmer than normal temperatures.   

Overall, the preliminary statewide average winter temperature was 28.8 degrees, 0.9 degrees below the 1991–2020 normal, 0.8 degrees above the 20th Century average, and 1.2 degrees below the most recent 30-year average. If confirmed, last season would be tied for 63rd warmest winter on record in Illinois.

Maps of average temperature departures from the 1991-2020 normals for December, January, February, and meteorological winter.
Figure 3. Maps of average temperature departures from the 1991-2020 normals for December, January, February, and meteorological winter.

Extremely Dry February Worsens Drought

February is normally one of the driest months of the year, but even among typically drier conditions last month was extreme. Total February precipitation ranged from less than a quarter of an inch in much of northern Illinois to just over 3 inches in isolated parts of south-central Illinois. The state was 1 to 4 inches drier than normal last month (Figure 4).

February total precipitation and February precipitation departure from normal.
Figure 4. February total precipitation (left) and February precipitation departure from normal (right).

Last month was the driest February on record in Moline (Trace), the second driest on record in Rockford (0.12”), the third driest on record in Chicago (0.16”), the third driest on record in Springfield (0.45”), the second driest on record in Champaign-Urbana (0.18”), the third driest on record in Carbondale (0.51”), and the second driest on record in Mt. Vernon (0.08”).

Not only was last month the driest February on record in Moline, but it was the only month (of any calendar month) on record there to not record any measurable precipitation. Records in Moline go back to 1872, meaning February 2026 was the driest month in the Quad Cities in the last 154 years, or – put another way – the driest month since at least the Ulysses S. Grant administration.

Although December and January were not as extremely dry as February, they were not remarkably wet either. The preliminary statewide total meteorological winter precipitation in Illinois was 3.24 inches, which is 3.73 inches below the 1991-2020 normal, 3.07 inches below the 20th Century average, and 3.75 inches below the most recent 30-year average. If confirmed, the 2025-26 winter season would be the fifth driest on record in Illinois, and the driest since 1976-77. The winter was the 7th driest on record in Springfield, the 5th driest on record in Champaign-Urbana, the 8th driest on record in Quincy, and the driest on record in Carbondale.

Flipped Snow Pattern in Illinois

I am contractually obligated to remind everyone that Illinois often – if not normally – gets some measurable snowfall in March, and occasionally in April. So, the “snowfall season” is not yet complete; however, meteorological winter (December – February) almost always contain most of the snowfall in the state. December brought an active winter stormtrack through central Illinois and produced above average snowfall for the northern half of the state, particularly along the Interstate 72 corridor between Quincy and Danville. January was exceptionally snowy in southern Illinois; however, much of northern Illinois experienced a snow drought. February united the entire state with a substantial lack of snow, and the 2025-26 meteorological winter overall was much snowier than normal in southern and parts of central Illinois, and it was a disappointing snow winter in northern Illinois (Figure 5).

Maps show snowfall departures from the 1991-2020 normals in December, January, February, and meteorological winter.
Figure 5. Maps show snowfall departures from the 1991-2020 normals in December, January, February, and meteorological winter.

March & Spring Outlooks

After a nearly record dry winter, we need rain in a bad way! Fortunately, March begins meteorological spring, which is typically one of the wettest seasons across Illinois. And even better news: the most recent Climate Prediction Center outlooks show good chances of wetter than normal weather in March (Figure 6). Models are also bullish for a milder start to spring with above average temperatures this month.

Climate Prediction Center temperature and precipitation outlooks for March.
Figure 6. Climate Prediction Center (left) temperature and (right) precipitation outlooks for March.

The spring season outlooks (March–May) also show higher chances of above normal precipitation, which is also good news. Meanwhile, there is not much of a temperature signal, with equal chances of a warmer and cooler than normal spring (Figure 7).  

Climate Prediction Center temperature and precipitation outlooks for March through May.
Figure 7. Climate Prediction Center (left) temperature and (right) precipitation outlooks for March through May.
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January Brought Winter Weather of Yore

The preliminary statewide average January temperature was 22.3 degrees, 4.4 degrees below the 1991-2020 average and tied for the 34th coldest on record going back to 1895. The preliminary statewide average total January precipitation was 1.25 inches, 1.06 inches below the 1991-2020 average and tied for the 32nd driest on record statewide.

Data are provisional and may change slightly over time.

Is this what winter used to be? 

All four of Illinois’ distinct seasons are getting warmer thanks to human-caused climate change; however, winter is warming far faster than the other seasons. As a result, we have experienced many more mild winters in recent decades; and this trend made last month’s persistently cold weather seem particularly extreme. Daily temperatures and departures from normal in Quincy show much of the first and third weeks of the month had temperatures that were consistently 5 to 30 degrees below normal (Figure 1).

Figure 1. Daily January average temperature departures in Quincy.

January average temperatures ranged from the high teens in northwest Illinois to the low 30s in southern Illinois, between 2 and 8 degrees below normal. Persistent snowpack in southern Illinois helped depress temperatures farther below normal than in relatively snow-less northern Illinois (Figure 2). The warmest point in the state last month was Du Quoin at 31.7 degrees, and the coldest point in the state was Stockton at 16.9 degrees. The few warm spells in January broke 10 daily high maximum temperature records. The extreme cold in the middle of the month broke 23 daily low maximum temperature records and 15 daily low minimum temperature records, including -20 degrees in Springfield.

Figure 2. Maps of (left) January average temperature and (right) January average temperature departures from normal.

Overall, the preliminary statewide average January temperature was 22.3 degrees, 4.4 degrees below the 1991-2020 average and tied for the 34th coldest on record going back to 1895.

Snowy Southern Illinois

Depending on who you talk to, January 2025 was either a very active winter weather month or quite a boring one. An active storm track setup across the southern half of the state in the first week of January, pushing multiple winter storms through the state, which produced multiple rounds of heavy snow mostly along and south of Interstate 70. The result was a strong gradient of snowfall opposite of what is typical for this time of the year, with more in southern Illinois than northern Illinois.

January total snowfall ranged from over 12 inches in south-central Illinois to less than 1 inch in northwest Illinois. Much of the southern half of the state had 1 to 8 inches more snowfall than normal in January, while northern Illinois racked up a 1-to-8-inch snowfall deficit (Figure 3). Last month was the fifth snowiest January on record in Fairfield with 15.6 inches and the snowiest since 1996. Meanwhile, Moline had only 2.3 inches of snow in January, the lowest amount since 2018 and fourth lowest there since 1989.

Figure 3. Maps of (left) January total snowfall and (right) January snowfall departures from normal

Other than a couple of noteworthy snow and ice events, January was otherwise mostly dry across Illinois. Total January precipitation ranged from just over 5 inches in far southern Illinois to less than a quarter of an inch in far northwest Illinois. Most of northern and central parts of the state were around 1 to 2 inches drier than normal last month and only the southern seven counties were wetter than normal (Figure 4).

Overall, the preliminary statewide average total January precipitation was 1.25 inches, 1.06 inches below the 1991-2020 average and tied for the 32nd driest on record statewide.

Figure 4. Maps show (left) January total precipitation and (right) precipitation departure from normal across Illinois.

Outlooks

The Climate Prediction Center outlooks, reflecting model tendencies and expert assessments, continue to lean into La Niña influence on our late winter and early spring weather across the U.S. Here in Illinois, the expectation is for near normal temperatures and above normal precipitation for both the last winter month of February and the first two months of spring (Figure 5).

Figure 5. Maps show (left) temperature and (right) precipitation outlooks for the month of February and February through April.  
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Warm, Dry December Concludes a Cold, Wet Year

December temperatures were well above the long-term average across the state, breaking dozens of local daily maximum and minimum temperature records. The preliminary statewide December average temperature was 35.2 degrees, about 5 degrees above the 1981-2010 normal and the 18th warmest on record. Preliminary data show December was drier than average for most of the state. The statewide average December precipitation total was 2.03 inches, 0.66 inches below the 30-year normal.

Data are provisional and may change slightly over time

Warm Weather

Temperatures during the first half of December were very close to average. This was followed by a brief period of well below average temperatures caused by cold air incursion from the north on the back of a strong upper atmosphere trough to our west. On December 20 the predominant wind direction changed to southwesterly, bringing warm, dry air into the region. Temperatures between December 20 and 29 ranged from 5 to 25 degrees above normal across the state. In total, 104 daily high maximum temperature records and 27 daily high minimum temperature records were broken over this time period, including a few dozen records on December 25. In fact, it was the warmest Christmas day at 68 stations across the state. As shown in the figure below, the daily average temperature in Decatur in Macon County on Christmas was nearly 20 degrees above the 30-year normal.

The station in Elgin (Kane County) broke its previous Christmas day high maximum record by 10 degrees. The highest temperature recorded in the state was 70 degrees on December 26 in Wayne County and again on December 29 in Pope County. The lowest temperature was -4 degrees on December 15 in Rock Island County.

A shift in the upper atmosphere and the passage of a cold front late in the month allowed temperatures to moderate. December average temperatures ranged from the low 30s in northern Illinois to the mid-40s in southern Illinois. Monthly average temperature departures ranged from 7 degrees above the long-term mean in northwestern Illinois to just over 1 degree above average in south-central Illinois.

The preliminary 2019 statewide average December temperature was 35.2 degrees, which was the 18th warmest December on record. December’s warm weather was an aberration in an otherwise colder than average 2019 in Illinois. Only three months this year–July, September, and December–exhibited a statewide average temperature above the 30-year normal.

Precipitation

December precipitation was below the long-term average for the entire state. Areas in far southern Illinois received 2 to 3 inches less than average in December, approximately 50 percent of normal December precipitation. The statewide average total December precipitation was 2.03 inches, approximately 0.66 inches below normal. This last month was the 50th driest December on record in Illinois and marked the second straight month of below average statewide precipitation. Preexisting wetness and reduced evaporative demand, typical for this time of the year, have prevented impacts from the prolonged dry conditions. Despite two straight months of well below average precipitation, streamflow and soil moisture were both near normal across the state.

Snowfall totals this last month ranged from less than a tenth of an inch in far southern Illinois to over 10 inches in south-central Illinois. A strong system came through in mid-December and brought several inches of snow to an area spanning the St. Louis Metro East to the Champaign-Urbana area. The highest 24-hour snowfall total was 5.6 inches in Lovington (Moultrie County) on December 17, although CoCoRaHS observers in Mascoutah in St. Clair County and Columbia in Monroe County both recorded 7.5 inches on December 17.

The December snowfall glut in south-central Illinois turned into snowfall deficits of 8 to 10 inches in northern Illinois. This last month was only the 10th December with 1 inch or less of snowfall in Stockton (Jo Daviess County). Despite the small snowfall totals this last month, the seasonal total snowfall was above average for most of the state between interstates 80 and 64. A broad area between Peoria and the St. Louis metro east received over 4 inches of above average snowfall, whereas the Chicagoland region has so far this season experienced a snowfall deficit of 4 to 6 inches.

Outlooks

Short-term 8-14-day outlooks from the NOAA Climate Prediction Center show strongly elevated odds of both above normal precipitation and above normal temperature.

Thirty-day outlooks show elevated odds of wetter and warmer than normal conditions to persist throughout January in southern Illinois. Outlooks for January through March and March through May continue to show elevated odds of above normal precipitation for the entire state.