January 2022 Overview
Temperatures and precipitation were below the long-term average in Illinois in January. Aggregate statistics of mean streamflow statewide were not available. Shallow groundwater levels were below the long-term depths.
Air temperatures averaged 22.3°F, 4.4° below the 1991–2020 normal for January (Figure 1). January average temperatures ranged from the low teens in northern Illinois to the low 30s in southern Illinois, between 2 and 8 degrees below normal.
Precipitation statewide in January was 1.09 inches, 1.22 inches below the long-term statewide average (Figure 1). Total January precipitation ranged from less than one-tenth of an inch in central Illinois to over 5 inches in far southern Illinois.
Mean provisional streamflow was estimated to be mostly in the normal range for January. Aggregate statistics of mean provisional flow statewide were not available for January 2022 due to frozen conditions at many streamgage stations.
Water surface levels at the end of January were below the full pool or target level at 6 of 23 reporting reservoirs. At the end of January, Lake Shelbyville was 1.4 feet above the winter target level, Carlyle Lake’s level was 0.1 foot above the winter target level, and Rend Lake was 1.9 feet above the spillway level. Lake Michigan’s mean level was above its long-term mean for the month.
Shallow groundwater levels statewide were 0.55 feet below the long-term average at the end of January (Figure 1). Levels averaged 0.72 feet below those in December 2021 and 0.66 feet below the January 2021 average.
Weather/Climate Information (Trent Ford)
The following description of temperatures, precipitation, snow, and drought comes from data compiled by networks that report to the National Oceanic and Atmospheric Administration (NOAA). These data are provisional and may change slightly over time.
January in Illinois was colder and drier than normal statewide.
Temperatures averaged 22.3°F, 4.4° below the 1991–2020 normal for January (Table 1, Figure 2). January average temperatures ranged from the low teens in northern Illinois to the low 30s in southern Illinois, between 2 and 8 degrees below the 1991–2020 normal (Figure 2). High temperatures reached into the mid- to high 60s in southern Illinois last month, including 68° in Pope County and 67° in Alexander County. Meanwhile, nighttime low temperatures frequently dipped below zero in central and northern Illinois in January, including lows of -22 degrees in Kane County and -20 degrees in Jo Daviess and Carroll counties.
The variable January temperatures broke four daily high maximum temperature records, three daily low maximum temperature records, and two daily low minimum temperature records.
Precipitation statewide in January was 1.09 inches, 1.22 inches below the long-term statewide average (Table 1). Only seven southern counties in Illinois were wetter than normal in January. Total January precipitation ranged from less than one-tenth of an inch in central Illinois to over 5 inches in far southern Illinois.
January precipitation patterns were like those in November and December, continuing the north-south, dry-wet pattern over the past 90 days. Since November 1, areas outside of far southern Illinois were 2 to 6 inches drier than normal. In fact, the period between November 1 and January 31 was the driest on record in Macomb, which has a record going back to 1903.
Snow essentially requires two ingredients: (1) cold-enough temperatures to permit the snow to reach the ground and (2) enough moisture in the air to precipitate as snow. In January we had enough cold air in the region, but the air was generally too dry to amount to much snowfall. January snowfall totals ranged from over 10 inches in parts of northern Illinois to less than half an inch in central and southern Illinois. Totals for the month were near to slightly above normal in far western Illinois and Chicagoland but were 1 to 8 inches below normal in central Illinois.
Drought: The dry conditions added to existing precipitation deficits in northern and western Illinois. Despite the pronounced dryness in January, drought conditions evolve slowly in winter, so there wasn’t much change in the U.S. Drought Monitor in January. Most areas between Whiteside County in northwest Illinois and Lake County in northeast Illinois remain in moderate to severe drought as nine-month precipitation deficits of 5 to 10 inches remain. Abnormal dryness expanded throughout much of western Illinois; however, the dryness in this region only goes back about three months, so much less precipitation is needed to take care of dry conditions, relative to the much deeper dryness in northern Illinois.
Illinois Climate Network (ICN) (Jennie Atkins)
The Illinois Climate Network (ICN) collects hourly weather and soil information from 19 stations across the state.
Wind speeds increased again in January to an average of 8.1 mph, 0.4 mph higher than in December but 0.2 mph lower than the network’s long-term average. ICN Bondville (Champaign County) had the highest average wind speed with 12.5 mph. The month’s highest wind gust, 45.2 mph, was measured at ICN Stelle (Ford County) on January 5.
Air temperatures fell to an average of 23° for the month, 18° cooler than in December and 5° cooler than the long-term average. The new year started out warm, especially in southern Illinois, which saw temperatures in the 60s on the first day of the year. ICN Brownstown (Fayette County) and ICN Dixon Springs (Pope County) both recorded highs of 63° on January 1, the month’s highest. Station highs were 10°–25° warmer than average.
However, Illinois did see colder temperatures, particularly toward the end of January. ICN St. Charles (Kane County) had a low of -19° on January 26, the network’s lowest of the month.
Soil temperatures fell 8° to 10° from in December to averages in the low to mid-30s. Under bare soil, temperatures ranged from 10° to 60° at 2 inches and 15° to 58° at 4 inches. Temperatures under sod ranged from 18° to 58° at 4 inches and 23° to 55° at 8 inches.
Precipitation remained below average at most ICN stations in January. Overall, the network averaged 1.38 inches for the month, 0.05 inches less than in December and 0.89 inches below the long-term average. Most stations in northern and central Illinois had totals of less than an inch. ICN DeKalb (DeKalb County) recorded 0.33 inches, 1.19 inches less than its long-term average.
However, the southern stations had a wetter month. ICN Dixon Springs recorded 4.72 inches, the month’s highest total.
Soil moisture data will return to the IWCS in Spring 2022.
Surface Water Information (Bill Saylor)
Provisional monthly mean flows for this month for 26 streamgaging stations located throughout Illinois are shown in Table 2, compared to statistics of the past record of monthly mean flows at those stations for the same month. Both recent and long-term data are retrieved from USGS online data services following the end of the month. Years of record values in Table 2 represent the number of past monthly values included in the Table 2 statistics; at some stations, the available record may not be continuous. Additional source data may be available from USGS.
The statewide percent of historical mean flow and percent of historical median flow are calculated by dividing the sum of the average flows this month at stations in Table 2 by the sum of the historical mean and median flows calculated for the month, respectively, at the same stations. This method is intended to weight individual observations proportionately in the aggregate comparison. (The Illinois River and Rock River stations are excluded from the statewide calculation because other rivers listed in Table 2 contribute to their flow.)
Aggregate statistics of monthly mean provisional streamflow statewide were not available for January 2022 due to frozen conditions at many streamgage stations. The limited amount of data posted suggests that monthly mean streamflow conditions were generally normal for January.
Water-Supply Lakes and Major Reservoirs. Table 3 lists selected reservoirs in Illinois, their normal pool or target water surface elevation, and data related to observed variations in water surface elevations. Reservoir levels are obtained from a network of cooperating reservoir operators who report water levels each month. Current reservoir levels reported in Table 3 are representative of the end of the reported month and are presented as the difference in feet from the seasonal target level or from full pool, as applies. Years of record represent the number of past reports for the same month used to calculate the average of the month-end values presented in Table 3. For some reservoirs, this average does not include an additional period of record prior to a substantial change in reservoir operation. Most reservoirs in Table 3 serve as public water supplies, with the exceptions noted in the last column.
Compared to end-of-December water levels at 23 reservoirs for which levels were reported last month and this month, reported end-of-January water levels were lower at 18 reservoirs, higher at 1 reservoir, and about the same as at the end of December at 4 reservoirs. For the 23 reservoirs with measurements reported at the end of January, water levels were below normal target pool or spillway level at 6 reservoirs, above normal target pool or spillway level at 9 reservoirs, and at about full pool level at 8 reservoirs. Kinkaid Lake’s level had recently been drawn down intentionally.
Major Reservoirs. Compared to water levels at the end of December, at the end of January the water level at Lake Shelbyville was 6.5 feet lower, Carlyle Lake was 1.4 feet lower, and Rend Lake was 0.3 feet higher. At the end of January, Lake Shelbyville was 1.4 feet above the winter target level, Carlyle Lake’s level was 0.1 foot above the winter target level, and Rend Lake was 1.9 feet above the spillway level.
Great Lakes. Current month mean and end-of-month values are provisional and are relative to International Great Lakes Datum 1985. The January 2022 mean level for Lake Michigan was 579.4 feet. The monthly mean level one year ago (January 2021) was 580.9 feet. The long-term average lake level for January is 578.4 feet, based on 1918–2020 data. In this period of record, the lowest mean level for Lake Michigan for January occurred in 2013 at 576.0 feet, and the highest mean level for January occurred in 2020 at 581.6 feet. The month-end level of Lake Michigan was 579.3 feet. All values are provided by the U.S. Army Corps of Engineers Detroit District.
Groundwater Information (Jennie Atkins)
Water tables declined at most monitoring wells in January. Well levels were 0.72 feet below December levels with individual well changes. The Brownstown well in Fayette County saw the largest drop with January 31 levels at 2.45 feet below last month. The largest increase was 0.70 feet at the Southeast College well in Saline County.
Statewide water levels averaged 0.66 feet below last year, 0.80 feet below the 15-year average, and 0.55 feet below the period of record. Water tables remain lower in northern Illinois as dry conditions continue in the region. The Mt. Morris well in Ogle County was 2.36 feet below last year’s levels and 5.13 feet below the period of record.
Data sources for the IWCS include the following:
CPC - Climate Prediction Center, https://www.cpc.ncep.noaa.gov/index.php
ISWS - Illinois State Water Survey, https://www.isws.illinois.edu
MRCC - Midwestern Regional Climate Center, https://mrcc.purdue.edu/
NCEI - National Centers for Environmental Information, https://www.ncei.noaa.gov
NWS - National Weather Service, https://www.nws.noaa.gov
SPC - Storm Prediction Center, https://www.spc.noaa.gov
USACE - U.S. Army Corps of Engineers, https://www.lre.usace.army.mil
USDM - U.S. Drought Monitor, https://droughtmonitor.unl.edu
USGS - U.S. Geological Survey, https://waterdata.usgs.gov/il/nwis
WARM - Water and Atmospheric Resources Monitoring Program, https://www.isws.illinois.edu/warm