Illinois State Climatologist

The preliminary statewide average March temperature was 47.3 degrees, 5.9 degrees above the 1991–2020 normal, 7.5 degrees above the 20th Century average, 5.3 degrees above the most recent 30-year average, and it tied for 9^th warmest March on record going back to 1895.

The preliminary statewide average total March precipitation was 4.85 inches, 1.91 inches above the 1991–2020 normal, 1.76 inches above the 20th Century average, 1.74 inches above the most recent 30-year average, and the 15th wettest March on record statewide and the wettest March since 1985.  

Data are provisional and may change slightly over time

March Temperature Roller Coaster

March temperatures had ebb and flow that is typical of spring in Illinois, but last month took that pattern to the extreme. As daily temperatures and departures from the 1991-2020 normals in Anna show, March temperatures were consistently 10 to 25 degrees above normal in the first half of the month, followed by a huge dip with temperatures 10 to 25 degrees below normal, and then a mixed but mostly warmer end to the month.

March average temperatures ranged from the high 30s in northwest Illinois to the high 50s in southern Illinois, between 5 and 11 degrees above the 1991-2020 normal (Figure 2).

Last month saw multiple waves of summer-like temperatures across the state, including daily highs of 93 degrees in Jacksonville and 89 in Bloomington-Normal. Dozens of locations across the state set new all-time March high temperature records, including 88 degrees in Champaign-Urbana, 92 degrees in Springfield, and 86 degrees in Carbondale. Many of the records, including those in Champaign-Urbana and Bloomington-Normal, were last broken well over 100 years ago.

A few stations’ high temperatures last month were also higher than their all-time April high temperature records, including 93 degrees in Jerseyville and 92 in Springfield. Speaking of Springfield, our state capital had its earliest 90 degree day on record last month. The previous earliest 90 degree day in Springfield was May 5^th of 1943, a full 40 days after the new record of March 26^th.

Very cold weather, while fleeting, did bring temperatures well below freezing across the state last month, including nighttime low temperatures of 4 degrees in Monmouth and 9 degrees in Aurora. The coldest place in the state last month was Stockton with an average of 39.0 degrees, while the warmest place in the state last month was Dixon Springs with an average temperature of 56.3 degrees.

The milder weather last month broke 88 daily high maximum temperature records in Illinois and 19 daily high minimum temperature records. Meanwhile, the brief cold spell in mid-Marh broke 11 daily low maximum temperature records and 7 daily low minimum temperature records.

Overall, the preliminary statewide average March temperature was 47.3 degrees, 5.9 degrees above the 1991–2020 normal, 7.5 degrees above the 20th Century average, 5.3 degrees above the most recent 30-year average, and it tied for 9^th warmest March on record going back to 1895.

Wet March Improves Drought

March is the transition month between the normally driest time of the year in the winter and the normally wettest time of the year in Illinois between April and July. Consequently, we have experienced previous years where March was extremely dry (only 1.13 inches in 1981) and those that were very wet (6.30 inches in 1973). This year March was more like the latter than the former, with most of the state experiencing well above average March precipitation.

March total precipitation ranged from around 2.5 inches in northwest Illinois to over 8 inches in parts of east-central Illinois. The entire state was 0.50 inch to 4.5 inches wetter than the 1991-2020 normals last month. The wettest part of the state was right around and slightly south of the Interstate 72 corridor from Springfield to Champaign-Urbana (Figure 4). Last month was the 3^rd wettest March on record in Springfield, the 8^th wettest in Bloomington-Normal, and the 6^th wettest in Aurora.

Overall, the preliminary statewide average total March precipitation was 4.85 inches, 1.91 inches above the 1991–2020 normal, 1.76 inches above the 20th Century average, 1.74 inches above the most recent 30-year average, and the 15th wettest March on record statewide and the wettest March since 1985.  

As expected, the wet March weather improved drought conditions that had stretched back to late summer 2025. The U.S. Drought Monitor reduced statewide coverage of all drought categories between March 3^rd and March 24^th, including 43% less of the state in at least moderate drought and 11% less of the state in extreme drought. Root zone soil moisture improved across the state, relieving some of the risk of early season agricultural drought. However, water table levels remained much deeper than typical for spring and streams also remained somewhat to very low as the calendar moved to April. These issues are lagged effects of the prolonged hydrologic drought in Illinois, and we will need continued wet weather through April and May to see consistent improvement in these conditions.

As is often the case in spring, abundant precipitation also meant abundant severe weather. An active storm track and sufficient humid, warm air moving into the Midwest produced multiple severe weather outbreaks in March. In all, the Storm Prediction Center listed 35 tornado reports in Illinois last month, including an EF3 tornado that moved through parts of Kankakee County on March 10^th. That same storm produced widespread gargantuan hail, including several stones reported to be as large as 5-6” in diameter. One of the hailstones that fell in Kankakee on March 10^th was measured by scientists at Northern Illinois University with a diameter of 6.616 inches. The current Illinois state hailstone record is 4.75 inches, which fell near Minooka in 2015. However, the State Climate Extremes Committee is currently reviewing the March 10^th storm and measured hailstone and will determine if it set a new state record.

This year marked the fourth consecutive March with at least 29 tornado warnings issued by National Weather Service offices serving Illinois. Prior to 2023, only one year (2006) had over 29 warnings issued, illustrating the remarkable stretch of active March severe weather recently (Figure 5).

Following the severe weather outbreaks around March 10^th, a short-lived but intense winter storm moved through northern Illinois, producing heavy snow. Snowfall exceeded 8 inches in parts of northern Illinois, especially between Rochelle and Rockford. However, an otherwise warm month left most places without significant snow in March.

April and Early Growing Season Outlooks

Climatological spring starts with March, but most folks associate spring more with April and May, as weather in Illinois begins to consistently feel springlike. April outlooks show better chances of warmer than average temperatures and wetter than normal conditions statewide.

Meanwhile, the outlook for April through June shows best chances of warmer than normal weather for much of Illinois, without a strong signal on precipitation.

The preliminary statewide average February temperature was 33.8 degrees, 2.8 degrees above the 1991–2020 normal, 4.6 degrees above the 20^th Century average, 2.8 degrees above the most recent 30-year average, and it tied for 29^th 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 20^th Century average, 1.65 inches below the most recent 30-year average, and the 5^th 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.

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.

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 20^th Century average, and 1.2 degrees below the most recent 30-year average. If confirmed, last season would be tied for 63^rd warmest winter on record in Illinois.

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).

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 20^th 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 7^th driest on record in Springfield, the 5^th driest on record in Champaign-Urbana, the 8^th 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).

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.

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).  

The preliminary statewide average January temperature was 23.5 degrees, 3.2 degrees below the 1991-2020 average and tied for the 41^st coldest on record going back to 1895. The preliminary statewide average total January precipitation was 1.19 inches, 1.12 inches below the 1991-2020 average and tied for the 28^th driest on record statewide.

Data are provisional and may change slightly over time.

A Tale of Two Temperature Months

Of all the crazy weather months in Illinois, January has the largest average day to day temperature variability, and those wild swings were on full display last month. Daily temperatures and departures from normal in Galesburg show that days in first half of the month was 5 to 25 degrees warmer than normal, and days in the second half of the month were 5 to 25 degrees colder than normal (Figure 1).

January average temperatures ranged from the high teens in northwest Illinois to the mid-30s in far southern Illinois, between 1 and 3 degrees below normal (Figure 2). Snowpack in the southern part of the state during the latter half of January kept both daytime and nighttime temperatures well below average, compared to relatively snow-less northern Illinois.

The warmest point in the state last month was Olmstead at 32.0 degrees, and the coldest point in the state was Stockton at 16.4 degrees. The warm start to the month broke 74 daily high maximum temperature records and 60 daily high minimum temperature records. The extreme cold in the back half of January broke 74 daily low maximum temperature records and 33 daily low minimum temperature records, including -13 degrees in Springfield. Lawrenceville set a new all-time January high temperature record of 68 degrees on January 9^th.

Overall, the preliminary statewide average January temperature was 23.5 degrees, 3.2 degrees below the 1991-2020 average and tied for the 41^st coldest on record going back to 1895.

Snowy, but Dry?

Last month was a good example of why snowy and wet are two different descriptions of winter weather. Multiple strong winter storms moved through the mid-south in the latter half of January, bringing a lot of snow to the southern half of Illinois. Five counties had locations that approached or exceeded their one-day snowfall records on Jan. 19, including over 13 inches in Jackson County. Although the heavy snow was disruptive to travel, it was preferable to the devastating ice accumulation farther south in places like Nashville.

Overall, January total snowfall ranged from less than 3 inches in northwest Illinois to some isolated pockets of 20 inches in southern Illinois. The northern half of the state only had 10-75% of normal January snowfall, while much of southern Illinois had 200-500% of normal snowfall (Figure 3). 

Plenty of cold air was present when the winter storms moved through our state in the latter half of January, and while this was helpful to produce some impressive snowfall totals, it also limited the liquid water content of the snow. Consequentially, parts of southern Illinois that had 300% or more normal snowfall were also 1 to 2 inches drier than normal last month. In fact, most of the state outside of a narrow band from Peoria to Chicago was 1 to 3 inches drier than normal last month (Figure 4). Only a few places saw more than 3 inches of total January precipitation, while some parts of northwest Illinois had less than an inch for the entire month.

Overall, the preliminary statewide average total January precipitation was 1.19 inches, 1.12 inches below the 1991-2020 average and tied for the 28^th driest on record statewide.

Drought Continues

Winter drought in Illinois is strange, both in concept and reality. Cold weather and dormant vegetation reduce evaporation, ice formation makes it hard to observe impacts on streams and in soils, and an abundant (but dry) snowpack can be deceiving. That said, there is no doubt that Illinois is still dealing with an intense drought that began in 2025. The period between August 2025 and January 2026 was a top 10 driest on record in most of central Illinois (Figure 5). Bloomington-Normal only received 7.10 inches of precipitation between Aug. 1 and Jan. 31, which was the fifth driest of any six-month period on record there and the driest six months since 1980.

The topsoil, once thawed, may be relatively wet because of recent snowmelt; however, measurements from the Illinois Climate Network show deeper layer soils, especially below 12-15” depth, are still very dry. The water table at the Illinois Climate Network station in Peoria is 8 feet deeper than normal this time of the year and is the deepest it has been since measurements began in the 1990s. Accordingly, the most recent US Drought Monitor released on Jan. 29 showed over 60% of the state was still in moderate drought, and much of east-central Illinois remained in extreme drought. Champaign County has been in extreme drought for 14 consecutive weeks ending on Jan. 29, marking the longest such period since the Drought Monitor began in 2000. Although we typically don’t expect a lot of precipitation in February, wetter weather this month would be very welcome to start improving long-standing drought in the state.

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 below normal temperatures this month, with equal chances of wetter and drier weather. Outlooks for February through April show better chances of wetter than normal weather to transition from winter and spring, which would be wonderful to make headway on our drought (Figure 5).

Illinois was both warmer and wetter than the 1991–2020 normal in 2025. The statewide average annual temperature was 53.6 degrees, 1.0 degree above normal and the 18^th warmest year on record statewide. Statewide average total precipitation in 2025 was 32.94 inches, 7.8 inches below normal and the 23^rd driest year on record statewide.

Another Very Warm Year in Illinois

The past year was very warm in Illinois, especially outside of climatological winter. March led the way with average temperatures that were over 6 degrees warmer than normal, and July, September, and October were all at least 2 degrees warmer than normal. Meanwhile, January and December were both 2 degrees colder than normal statewide, and below normal temperatures in February, May, and August as well (Figure 1).  

Average temperatures in Illinois last year ranged from the high 40s in northern Illinois to the high 50s in southern Illinois, between 1 and 3 degrees above normal (Figure 2). The year 2025 was the 15^th warmest on record in Chicago, and the 20^th warmest on record in Peoria. The warmest point in the state last year was Bean Ridge in Alexander County with an average temperature of 60.5 degrees. The coolest point in the state was Stockton in Jo Daviess County with an average temperature of 48 degrees.

Although 2025 was not nearly as warm statewide as 2024, the average temperature in Illinois last year was still well above the 20^th century average. Last year was indeed another data point in a clear warming trend in Illinois, indicative of our changing climate (Figure 3). Models project continued warming in Illinois throughout the rest of this century, as summarized in the 2021 Illinois Climate Assessment and 2023 National Climate Assessment. 

Table 1 shows the number of daily weather records broken at Illinois Cooperative Observer stations in each month of 2025. A brief but intense cold spell in February broke 64 daily low maximum temperature records and 36 daily low minimum temperature records. Our very mild, if not warm, March broke 77 daily high maximum temperature and 41 daily high minimum temperature records. Meanwhile, intense June humidity broke to 102 daily high minimum temperature records, and storms in July broke 90 daily precipitation records statewide. Overall, 679 high daily record temperatures were broken last year, 418 low daily record temperatures were broken, and 435 daily precipitation records were broken.

Daily	High Maximum Temperature	High Minimum Temperature	Low Maximum Temperature	Low Minimum Temperature	High Precipitation
January	9	28	27	13	21
February	24	16	64	36	24
March	77	41	0	0	33
April	12	5	3	0	73
May	39	8	32	1	50
June	14	102	2	1	46
July	1	23	4	0	90
August	3	29	24	44	17
September	65	3	6	17	12
October	27	10	0	1	48
November	42	13	5	3	12
December	43	45	69	66	9
Total	356	323	236	182	435

Overall, the statewide average annual temperature was 53.6 degrees, 1.0 degree above normal and the 18th warmest year on record statewide.

2025 Precipitation

Calendar year 2025 was very dry in Illinois, as all but 2 months last year were drier than normal (Figure 4). Only April and July were wetter than normal statewide. Some of the more extreme precipitation months included the 6^th driest August on record statewide (1.74 inches), the 11^th driest September on record (1.36 inches), and the 9^th wettest July on record (6.23 inches).

As is seemingly a perennial occurrence, June and July brought multiple rounds of extremely heavy rainfall in Illinois. Most of far southern Illinois had 8 to 10 inches of precipitation in June, following an extremely wet late spring in the region. Following the very wet month of June, parts of Fayette County in south-central Illinois experienced more than 12 inches of rain in a single day. Never to be outdone, the Chicagoland was subsequently impacted by extremely heavy rainfall in July, Including over 5 inches of rain in less than 90 minutes around the United Center on the west side.

For the fourth consecutive year Illinois fell back into drought in the late summer and fall as each of the last five months of the year were at least 0.75 inches drier than normal statewide. Total precipitation in August and September statewide was only 3.1 inches, less than 50% of normal and the third driest August to September period on record in Illinois. Once again, the region’s largest rivers approached low stage, including along the Illinois, Mississippi, and Ohio Rivers, causing some moderate challenges to shipping. The dry fall weather was beneficial to harvest, but depleted moisture throughout the soil and caused near-record low flow conditions in several Illinois streams including the Sangamon and Vermilion Rivers. Dry conditions persisted through the rest of fall and into the first month of winter, causing a significant expansion of moderate to extreme drought across Illinois.

Figure 5 shows the spatial variability of 2025 precipitation in more detail. Total precipitation last year ranged from nearly 60 inches in far southern Illinois to less than 30 inches in east-central Illinois. Much of southern and southeast Illinois were 1 to 5 inches wetter than normal in 2025, while most of central and northern Illinois were 1 to 10 inches drier than normal (Figure 5).

A CoCoRaHS citizen science observer in Metropolis in Massac County had 67.09 inches of precipitation in 2025, making the birth of Superman the wettest point in the state for two consecutive years. Meanwhile, two other CoCoRaHS observer in Savoy in Champaign County and White Heath in Piatt County had less than 22 inches of precipitation in 2025. Last year was the 2^nd driest year on record in Champaign-Urbana and the driest since 1894 with only 24.45 inches. 2025 was also a top 10 driest year on record in Peoria and Springfield, and the 12^th driest on record in Quincy. 

Overall, Statewide average total precipitation in 2025 was 32.94 inches, 7.8 inches below normal and the 23rd driest year on record statewide.

2025 Severe Weather

Following the most tornadoes on record statewide in 2024, Illinois had another very active severe weather year… at least until July. Overall, the NOAA Storm Prediction Center reported a preliminary 146 tornadoes in 2025, but that total will likely decrease before the official count is released. Figure 6 shows the monthly frequency of tornadoes in 2025 compared to the 1995-2024 averages. March through June had well above average tornado frequency, followed by a large dropoff in tornadoes, and storms more generally, between August and November. It is likely the 2025 tornado total will be adjusted, but irrespective of changes, the year was another extremely active tornado year in Illinois.

The NOAA Storm Prediction Center also had 167 severe hail reports and 656 severe wind reports in Illinois in 2025. Some of the wind reports came from strong, non-thunderstorm winds that caused a dust storm in central and northern Illinois, including the city of Chicago in mid-May.

2025 Snowfall

Snowfall in calendar year 2025 was a tale of two very different seasons. As shown in Figure 7, most of the state had 3 to 18 inches below average snowfall between January and May last year, with the exception of a band of snowier weather in southern Illinois. However, multiple rounds of heavy snowfall in November and December gave much of central and northern Illinois 10 to 20 inches above average snowfall, somewhat evening out the lackluster spring snow (Figure 7). Overall, 2025 ended with snowfall deficits between 3 and 10 inches in northern Illinois, and snowfall surpluses between 3 and 15 inches in central and southern Illinois.

While 2025 didn’t break any snowfall records for the state, it was considerably snowier than recent years. In fact, 2025 was the first year where the statewide average snowfall was above the 1991-2020 normal since 2021, and was the snowiest year in Illinois since 2019 (Figure 8).

The preliminary statewide average December temperature was 29.1 degrees, 2.5 degrees below the 1991–2020 average and tied for 53^rd coolest on record going back to 1895. The preliminary statewide average total December precipitation was 1.50 inches, 0.93 inches above the 1991–2020 average and the 29^th driest on record statewide.

Data are provisional and may change slightly over time.

Roller Coaster Temperatures

Day-to-day temperature variability in Illinois is highest in climatological winter, and December followed suit with huge dips and jumps in daily temperature, as shown in Figure 1 from Decatur. Daily average temperatures were 25 to 40 degrees below normal in the second week of the month and were 15 to 25 degrees above normal days around Christmas (Figure 1). Decatur broke its daily low temperature record with a -14-degree low on December 14^th and broke a daily high temperature record with a 69-degree high on December 28^th.

When taken altogether, December average temperatures ranged from low 20s in northwest Illinois to low 40s in far southern Illinois. December was 1 to 5 degrees cooler than normal in the northern half of the state, and near to around 1 degree warmer than normal in southern Illinois (Figure 2). The warmest place in the state last month was Olmstead in Pulaski County with an average December temperature of 38.4 degrees. The coolest place in the state was Stockton in Jo Daviess County with an average December temperature of 22.3 degrees.

The extremely mid days last month broke 43 daily high maximum temperature records and 45 daily high minimum temperature records. Morrisonville in Christian County broke its all-time December high temperature record with a 72-degree high on December 29^th. Meanwhile the extreme cold mid-month broke 69 daily low maximum temperature records and 66 daily low minimum temperature records. Six places broke their all-time December low minimum temperature records, including -14 degrees in Decatur and -10

Overall, the preliminary statewide average December temperature was 29.1 degrees, 2.5 degrees below the 1991–2020 average and tied for 53rd coolest on record going back to 1895.

The Paradox of a Dry December with Plentiful Snow

December reminded us of the difference between total precipitation and total snowfall. Most folks think about snowfall as inches of accumulation, but for the climate and our water balance, the liquid water content of the snow that matters most. Case in point, northern and central Illinois had higher-than-normal snowfall last month, with totals ranging from 3 to 20 inches (Figure 3). Parts of central Illinois received over 400% of normal December snowfall, including 15.5 inches in Fisher and 12.8 inches in Bloomington. However, one inch of snowfall in Illinois usually yields between 0.05 inches and 0.10 inches of liquid water, meaning that even the highest snowfall totals last month equated to only around 1 to 2 inches of liquid precipitation.

Overall, December total precipitation ranged from around 4 inches in northeast Illinois to less than half an inch in southwest Illinois (Figure 4). Most of the northern half of the state was near to slightly wetter than normal last month, while the southern half of the state was 1 to 3 inches drier than normal. Morrisonville had its driest December on record (going back to 1948) with only 0.60 inches last month.

Overall, the preliminary statewide average total December precipitation was 1.50 inches, 0.93 inches above the 1991–2020 average and the 29th driest on record statewide.

Outlooks

Climate Prediction Center outlooks for January show an extension of colder-than-normal conditions from the northern Plains into much of northern Illinois and the Great Lakes region. January Outlooks show equal chances of above and below normal precipitation for the first month of 2026 (Figure 5).

The preliminary statewide average November temperature was 43.6 degrees, 1.4 degrees above the 1991-2020 average and the 32^nd warmest November on record. The preliminary statewide average total November precipitation was 2.14 inches, 0.94 inches below the 1991-2020 average and the 45^th driest on record statewide.

Data are provisional and may change slightly over time.

Mild November with a Chilly End

November is the final month of meteorological fall, and as such represents a transition between fall and winter. Accordingly, November weather can bring tastes of both seasons, and last month followed suit. November daily average temperatures and temperature departures from normal in Rockford show most of the first two-thirds of the month had warmer than normal temperatures, including a few days that were 15 to 20 degrees warmer than normal (Figure 1). However, temperatures dropped into winter territory right around Thanksgiving, with averages 5 to 10 degrees below normal.

November average temperatures ranged from the high 30s in northern Illinois to the high 40s in southern Illinois, which despite the late month cool down, was 1 to 3 degrees warmer than normal (Figure 2). Several stations saw high temperatures push into the high 70s and even low 80s in the middle of the month, including 80-degree highs in Cahokia Heights and Morrisonville. Meanwhile, the last week of the month brought some very low nighttime minimum temperatures, including 11 degrees in Rockford and 15 in Galesburg. The coldest point in the state last month was Stockton at 38 degrees, and the warmest point was Smithland Lock and Dam in Massac County at 49.1 degrees.

Overall, the preliminary statewide average November temperature was 43.6 degrees, 1.4 degrees above the 1991-2020 average and the 32^nd warmest November on record.

Mixed Bag of November Precipitation

September and October were both dry months across Illinois, especially in the northern half of the state. While November wasn’t a washout by any means, some of the drier areas of the state did get significantly more precipitation, in many forms. Total precipitation last month ranged from nearly 6 inches in central Illinois to less than 2 inches in east-central Illinois (Figure 3). Much of northern Illinois and parts of central Illinois were 1 to 4 inches wetter than normal, while most of southern Illinois was 1 to 3 inches drier than normal. Some of the more impressive November totals include 7.48 inches in Streator and 7.41 inches in Lombard.

Overall, the preliminary statewide average total November precipitation was 2.14 inches, 0.94 inches below the 1991-2020 average and the 45^th driest on record statewide.

Early Snow Brings Hope for More

Snowfall in November is not a rare occurrence but certainly is not a mainstay in Illinois. This year, the northern half to two-thirds of the state experienced moderate to heavy snowfall in the final few days of the month. Earlier in November, unusually intense lake-effect snowfall accumulated in the eastern half of the state, stretching all the way down to Evansville, Indiana. November snowfall totals ranged from nearly 18 inches in far northeast Illinois to no measurable snowfall in much of southern Illinois. The two big rounds of snowfall last month made for a much snowier than average November for central and northern Illinois, as some places picked up 8 to 12 inches above normal snow.

Last month was a top 10 snowiest November on record in many places, including the sixth snowiest in Rockford (10.0 inches) and Moline (9.2 inches), the fifth snowiest in Champaign-Urban (8.4 inches), and the third snowiest in Springfield (8.9 inches).

A Mild and Dry Fall in Illinois

Climatological fall includes September, October, and November, and — for my money — it is the best weather season Illinois has to offer. This fall’s average temperatures ranged from the low 50s in northern Illinois to the low 60s in southern Illinois, between 1 and 5 degrees warmer than normal (Figure 5a). It was a top 10 warmest fall in many places including the sixth warmest in Champaign-Urbana and Salem. Overall, the preliminary statewide average temperature in fall was 57.4 degrees, 2.8 degrees above the 1991-2020 normal and the eighth warmest fall on record in Illinois.

Fall season total precipitation ranged from over 14 inches in southern Illinois to less than 4 inches in east-central Illinois (Figure 5b). Only parts of southern Illinois were wetter than normal, while much of central and northern Illinois were 4 to 7 inches drier than average. Last season was a top 10 driest fall on record in Peoria (3.67 inches), Danville (3.81 inches), Decatur (4.73 inches), and Galesburg (4.43 inches). Overall, the preliminary statewide fall total precipitation was 6.28 inches, 3.41 inches below the 1991-2020 normal and 21^st driest fall on record in Illinois. Last season was also the sixth consecutive drier than normal fall in Illinois.

Outlooks

Welcome to winter! December brings in the coldest, snowiest season — although it feels like winter started in November this year. The newest Climate Prediction Center outlooks for the month of December show best chances of colder than normal temperatures with near normal precipitation. The final meteorological winter season outlooks are leaning into La Niña conditions in the Pacific Ocean, with best chances of colder and wetter than normal weather. Let winter rip!

The preliminary statewide average October temperature was 59.6 degrees, 4.8 degrees above the 1991-2020 average and tied for 9^th warmest on record going back to 1895. The preliminary statewide total October precipitation was 2.61 inches, 0.65 inches below the 1991-2020 average and the 67^th driest on record.  

Data are provisional and may change slightly over time.

Mild October Temperatures

October is the most quintessential fall month, weather-wise, as we transition from a more summer-like September to what is often a more winter-like November. This year, October played to type and moved from summer-like warmth in the first half to real fall days in the second half. Temperature departures from normal in Olney show daily average temperatures in the first half of the month regularly reached into the 70s, between 8 and 12 degrees above normal. A cool down around October 20^th pushed most of the rest of the month’s temperatures slightly cooler than normal (Figure 1).

October average temperatures ranged from the high 50s in northern Illinois to the mid-60s in southern Illinois, between 2 and 7 degrees above average (Figure 2). High temperatures regularly reached into the high 80s and low 90s in early October, including 93 degrees in Minonk and 92 in Charleston. However, low humidity helped nighttime temperatures dip into the 20s and 30s on m any nights, including 26 degrees in Moline and 31 in Mt. Vernon.

The coolest point in the state last month was Barrington in Lake County at 55.1 degrees, and the warmest point was Morrisonville in Christian County at 64.1 degrees. Last month was a top 10 warmest October on record in several places, including Champaign-Urbana (6^th warmest). Unusually high temperatures in early October broke 28 daily high maximum temperature records and 7 daily high minimum temperature records. Two places, McHenry and Normal, broke all-time October high maximum temperature records with highs of 90 and 92 degrees, respectively, in the first week of the month. Only 1 daily low minimum temperature record was broken last month.

Overall, the preliminary statewide average October temperature was 59.6 degrees, 4.8 degrees above the 1991-2020 average and tied for 9th warmest on record going back to 1895.

Dry North, Wet South… Again

October precipitation has a strange perception in Illinois, especially for agriculture. While our soils and streams usually need a good drink of water coming out of the summer, too much rain can delay harvest, winter wheat and cover crop planting, and other necessary fall fieldwork. This year, though, October rain was mostly not an issue because (1) harvest progressed very quickly and (2) rain was hard to come by north of Interstate 70.

The first half of October was quite dry and extended drought conditions statewide from September. A significant weather pattern shift that coincided with the mid-month cooldown brought more frequent and substantial rain, especially in southern Illinois. Overall, October total precipitation ranged from around 0.90 inches in western Illinois to over 6 inches in parts of southern and south-central Illinois. Most of the state south of Interstate 70 was 1 to 4 inches wetter than normal in October, while most of central and northern Illinois were 1 to 3 inches drier than normal (Figure 3).

Overall, the preliminary statewide total October precipitation was 2.61 inches, 0.65 inches below the 1991-2020 average and the 67^th driest on record

Drought Continues in Central Illinois, Improves in Southern Illinois

Below normal rainfall continued from August and September into October in central and northern Illinois. Most of central Illinois has been 5 to 10 inches drier than normal since August 1^st, less than 50% of normal over that time. The dry weather helped harvest progress very quickly, but also created some challenges with dry vegetation and high fire risk. Dozens of field fires were reported across the state in the first two weeks of October, including one that burned over 1,000 acres in north-central Illinois. Many rivers and streams remain at or near low-flow, including extremely low levels on the Sangamon and Vermilion Rivers.

In contrast, drought was eased or altogether broken in much of southern Illinois, thanks to abundant rainfall in October. The U.S. Drought Monitor released on October 28^th showed significant drought improvement in southern Illinois, including many places that went from severe drought (D2) in the beginning of the month to abnormal dryness (D0) at month’s end (Figure 4).

Outlooks

month of the year can bring all four seasons, including tornadoes touching down on ground with some snowpack. Quintessential November weather, though, is infinite thick clouds… break out the crock pot.

The latest outlooks from the Climate Prediction Center lean to a warmer than normal November across Illinois, but equal chances of wetter and drier than normal weather (Figure 5). A wet November would be something to be thankful for, to help with drought.

Outlooks for the period from November to January continues to lean warmer than normal, but we start to see better chances of wetter than normal conditions as we move into the heart of winter.

Below normal rainfall has continued into fall and has both expanded and worsened drought conditions across the state. Dry vegetation and crops have caused dozens of field fires over the past two weeks. Multiple rivers have hit low- or no-flow, including the Sangamon and Vermilion, and some municipalities have begun to enact voluntary water conservation measures. The short-term forecast shows dry weather will likely persist through mid-October, and longer outlooks do not show strong signs of substantially wetter weather through at least the end of October.

Drought Intensifies as the 2025-26 Water Year Begins

Very dry weather in August, September, and the first week of October caused a significant expansion and intensification of drought across Illinois. The October 7^th edition of the U.S. Drought Monitor shows at least moderate drought in 86% of the state, severe drought in 43% of the state, and a small area of extreme drought in east-central Illinois.

Maps in Figure 1 show much of central and northern Illinois were 8 to 15 inches drier than normal for the 2024-25 water year (October 1, 2024 – September 30, 2025), and parts of east-central Illinois have been 10 to 13 inches drier than normal in the 2025 calendar year.

Low River Levels Across the Midwest

Drought usually affects the flow and level of small streams and creeks first, then the tributaries of our larger rivers. When dry conditions persist for weeks to months we can see low flow along our larger rivers. Persistently dry conditions have caused very low levels along many of our state’s rivers, including the Sangamon, Vermilion, Embarras, Kaskaskia, and the Illinois River.

Very low levels and flow along the Sangamon River have added to dry and warm weather to cause several central Illinois lakes and reservoirs to drop quickly. As of October 9^th, Lake Decatur was 2.4 feet below the normal level and the City of Decatur has requested voluntary water conservation as the lake continues to drop.

Fire and Dust Risk

Recent rain has helped reduce field fire risk in many places. However, fire risk remains somewhat to very high, especially in central Illinois. We saw dozens of field fires across the state over the past two weeks, illustrating the continued fire risk. Extra precautions should be taken ahead of, during, and after harvest to ensure everyone stays safe considering the enhanced fire risk. You can find more information on farm fire safety here: go.illinois.edu/farmfiresafety.

Where are We Headed?

The October 7 edition of the U.S. Drought Monitor has over 86% of the state in at least moderate drought, which is up from just 6% of the state in late August. The Drought Monitor also has extreme drought (D3) in east-central Illinois for the first time since 2012.

Unfortunately, the next 7-days look to be dry once again across most of the state (Figure 3). Despite the recent unusually warm weather, the seasons work in our favor now, because our average temperatures will drop as we continue through fall and into winter, which will at least limit evaporation from streams and lakes. Climate Prediction Center outlooks for the third week of October show a return to unusually warm weather, with no strong signal of wetter weather in sight.

In summary: we expect drought conditions across the state will likely continue to worsen in coming weeks, albeit at a slower rate because of cooler weather and some beneficial rainfall in far southern Illinois.

The preliminary statewide average September temperature was 68.8 degrees, 2.0 degrees above the 1991–2020 average and tied for the 27th warmest on record going back to 1895. The preliminary statewide total September precipitation was 2.60 inches, 0.75 inches below the 1991–2020 average and the 41^st driest on record.

Data are provisional and may change slightly over time.

Fall Start and Summer Finish

September is a transition month as we move from summer into fall. In very September form, the month began with a brief taste of fall-like weather. Temperatures in Monmouth were 5 to 12 degrees below normal in the first 10 days of the month (Figure 1). Summer heat returned in the latter two-thirds of September, with several days that were 5 to 15 degrees warmer than normal statewide.

September average temperatures ranged from the high 60s in northern Illinois to the mid-70s in southern Illinois, between 2 and 5 degrees above normal (Figure 2). High temperatures regularly reached the 90s in mid- and late September, including 99 degrees in Mt Vernon and Charleston. Meanwhile, cooler air in the first half of the month brought nighttime low temperatures in the 30s across much of the state, including 37 in Lincoln and 38 in McHenry. The coolest point in the state was Stockton with an average temperature of 64.3 degrees and the warmest part of the state was Smithland Lock & Dam in Massac County with an average temperature of 72.6 degrees.

The summer-like heat last month broke 51 daily high maximum temperature records and 3 daily high minimum temperature records across the state. The brief cold spell in early September broke 6 daily low maximum temperature records and 17 daily low minimum temperature records. Overall, the preliminary statewide average September temperature was 68.8 degrees, 2.0 degrees above the 1991–2020 average and tied for the 27th warmest on record going back to 1895.

Another Dry Month in Illinois

September is not usually a very wet month across Illinois, but September precipitation is still important to finish the soybean crop, help along late harvested specialty crops, give our trees and other plants one last drink before winter, and keep our streams above low flow. Unfortunately, very dry conditions last month, following an extremely dry August, did none of those things. Total September precipitation ranged from less than a quarter of an inch in northwest Illinois to over 5 inches in parts of southern Illinois. Only the south seven counties were wetter than normal last month, while a large swath of central and northern Illinois were 2 to 4 inches drier than normal (Figure 3).

The preliminary statewide total September precipitation was 2.60 inches, 0.75 inches below the 1991–2020 average and the 41^st driest on record.

Drought Returns in Illinois

Very dry weather in August and September caused a significant expansion and intensification of drought across the state. The September 23^rd edition of the U.S. Drought Monitor had moderate drought in 67% of the state and severe drought in nearly 20% of the state, when just 3 months ago only 10% of the state was in any drought level. The dry transition from summer to fall was a substantial pattern change from the extremely wet conditions in spring in southern Illinois. In fact, some areas of the south-central part of the state were having a top-5 wettest year as recently as mid-July, but has only had 10-25% of normal rainfall since then. Meanwhile, the recent dryness has only added to what has been a very dry calendar year and water year (October 1 – September 30) in parts of central and northern Illinois.

Figure 4 shows precipitation departures from normal for the 2024-25 water year (October 1, 2024 – September 30, 2025) and the 2025 calendar year so far. Most of the state north of Interstate 64 was 5 to 10 inches drier than normal in this past water year, with most of the deficit coming in the calendar year 2025. Parts of east-central Illinois, including much of Champaign County, has had over 1 foot less precipitation than normal since the start of 2025. This year to date is the 6^th driest on record in Champaign and the driest since 1988. Amazingly, we’ve had 5 fewer inches of precipitation this year in Champaign than in 2012. This year to date is also the 10^th driest year on record in Peoria.

Outlooks

October – in my humble opinion – is the best weather month of the year. Days become noticeably shorter, nights become cooler, and hoodies and shorts become the fashion. However, we may need to wait a bit longer for real fall, because the Climate Prediction Center shows higher odds of a warmer than normal October (Figure 6). Unfortunately, the outlooks also show best chances of another drier than normal month in October.

The most recent outlooks for climatological winter are continuing to lean toward La Niña effects of near normal temperatures but above normal precipitation across much of the state. A wetter late fall and winter would be welcome to improve drought conditions and recharge our soils and streams. For now, let’s enjoy the best of the four seasons.