November 2022 Overview
November temperatures were above and precipitation was below the long-term average in Illinois. Mean streamflow statewide was below the median for the month. Shallow groundwater levels were below the long-term depths.
Air temperatures averaged 42.8 degrees F, 0.6 degrees above the 1991–2020 normal for November (Figure 1). November average temperatures ranged from the high 30s in northern Illinois to the low 50s in southern Illinois.
Precipitation statewide in November was 1.78 inches, 1.3 inches below the long-term statewide average (Figure 2, Table 1a). Total November precipitation ranged from nearly 4 inches in northwest Illinois to less than 1.5 inches in east-central and southeast Illinois.
Soil moisture at 2-inch depths rose 16 percent in November to a state average of 0.33 water fraction by volume (wfv). Levels at 4 and 8 inches rose 12 and 14 percent, respectively. Moisture levels remained steady at 20 inches and greater.
Mean provisional streamflow aggregated statewide was below the long-term median flow for November, about 70 percent of median (Figure 1). Monthly mean discharge values in November ranged mostly from below normal to normal.
Water surface levels at the end of November were below the full pool or target level at 17 of 20 reporting reservoirs. At the end of November, Lake Shelbyville was 0.9 feet below the December 1 target level, Carlyle Lake was 0.2 feet below the December 1 target level, and Rend Lake was 0.2 feet below the spillway level. Lake Michigan’s mean level was above its long-term mean for the month.
Shallow groundwater levels were 1.9 feet below the long-term average at the end of November (Figure 1). Levels averaged 0.3 feet below those in October and 2.5 feet below last year’s levels.
Weather/Climate Information
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.
November in Illinois was slightly warmer and much drier than average statewide.
Temperatures averaged 42.8 degrees F, 0.6 degrees above the 1991–2020 normal for November (Table 1a). November average temperatures ranged from the high 30s in northern Illinois to the low 50s in southern Illinois, within 1 degree of normal in the northern half of the state and between 1 and 3 degrees below normal in southern Illinois (Figure 2). The warmest spot in the state last month was Dixon Springs in Pope County with an average temperature of 46.7 degrees, and the coolest spot in the state was Elizabeth in Jo Daviess County with an average temperature of 38.7 degrees.
Several places in the state had temperatures reach into the low to mid-80s in the first 10 days of November, including 82 degrees in Cahokia Heights and Cairo. Meanwhile, the cold air outbreak in the middle of the month brought nighttime low temperatures into the teens and single digits across the state, including 8 degrees in Monmouth and Champaign. Any place that missed out on a 28-degree hard freeze in October reached that mark multiple times in November.
Precipitation statewide in November was 1.78 inches, 1.3 inches below the long-term statewide average (Figure 3, Table 1a). Total November precipitation ranged from nearly 4 inches in northwest Illinois to less than 1.5 inches in east-central and southeast Illinois. Only the northwest sliver of the state was wetter than normal last month, while southeast Illinois was 2 to 3 inches drier than normal (Figure 3).
Snow: Despite the drier weather in November, virtually all the state saw near to above normal snowfall last month. As Figure 5 shows, November snowfall totals ranged from over 7 inches in southwest Illinois to just less than 1 inch in central Illinois. All areas south of Interstate 80 had above normal snowfall, while northern Illinois had just less than normal November snowfall. A strong low-pressure system swung through the middle
Mississippi region in mid-November and brought sometimes heavy snow to the St. Louis Metro East area. Parts of Belleville, Mascoutah, and Breese picked up between 6 and 8 inches of snow in just a few hours. Waterloo in Monroe County had 8.4 inches of snow last month–most of which came from that one storm–making it the second snowiest November on record there (after 1980).
The November snowfall in southern Illinois was not only unusually heavy, but was also abnormally early, especially in far southern Illinois. Paducah, Kentucky–just across the Ohio River from Brookport in Massac County–had its first measurable snow on November 11 this year, the third earliest on record.
Drought: Outside of parts of southwest, east-central, and northwest Illinois that experienced very heavy rain in mid- to late summer, most of Illinois has been somewhat to much drier than normal since July. Long-term precipitation deficits are largest in southern Illinois, where areas from Carbondale to Metropolis have had only 50–60 percent of normal rainfall since July 1.
Unfortunately, the mild fall temperatures were accompanied by drier weather, extending drought conditions across the state. Most parts of the state were drier than normal in at least two of the three fall months, and all three months were drier than normal in southern Illinois. The result of the dry weather was a continuation–and in some cases, worsening–of drought conditions across the state. The latest U.S. Drought Monitor shows severe to extreme drought across southern Illinois and moderate drought in north-central and northeast Illinois. Although ecological impacts have diminished as we move closer to winter, drought impacts to hydrology have continued. These impacts include low stream, lake, and pond levels across the state and low flow on the Illinois and Mississippi Rivers.
Fall (September–November) was slightly cooler than normal across most of Illinois. Seasonal temperatures averaged 54.4 degrees F, 0.2 degrees below the 1991–2020 normal (Table 1b). While September and November were very near to slightly cooler than normal, October was 1–3 degrees cooler than normal, pushing the fall season average below the 30-year average.
Fall was much drier than normal, as total fall precipitation averaged 6.52 inches statewide, 3.17 inches below average (Table 1b). Only parts of west-central and northwest Illinois were wetter than average in fall, and far southern Illinois was 5–7 inches drier than normal for the season. While last season was the 23 driest fall on record statewide, it was the third driest on record in Alexander County in southern Illinois.
Illinois Climate Network (ICN) (Jennie Atkins)
The Illinois Climate Network (ICN) collects hourly weather and soil information at 19 stations across the state.
Wind increased in November to an average of 7.8 mph, 1.6 mph higher than in October, but 0.1 mph lower than the network’s long-term average. ICN Monmouth (Warren County) had the windiest month with an average wind speed of 12.1 mph. The highest recorded wind gust was 54.6 mph, measured at ICN Bondville (Champaign County) on November 5.
Temperatures averaged 42 degrees F for the month, 11 degrees lower than in October and 1 degree lower than the long-term average. Warmer weather in the first 10 days of the month brought highs in the 70s and 80s for all stations. The month’s highest temperature was 83 degrees, measured at ICN Carbondale (Jackson County) on November 9.
Cooler temperatures during the middle of the month led to monthly lows in the single digits and teens for all stations. ICN Monmouth (Warren County) had the month’s lowest temperature, recording 7 degrees on November 20.
Soil temperatures averaged in the mid- to high 40s, 10 to 12 degrees lower than in October. Under bare soils, temperatures ranged from 19 to 77 degrees at 2-inch depths and 25 to 73 degrees at 4 inches. Temperatures under sod ranged from 29 to 66 degrees at 4 inches and 35 to 65 degrees at 8 inches.
Precipitation averaged 2.06 inches in November, 0.15 inches less than in October and 1.01 inches lower than the long-term average. ICN Freeport (Stephenson County) had the month’s highest total with 3.95 inches, 1.69 inches above its long-term average. All other stations had lower than normal precipitation. ICN DeKalb (DeKalb County) had the lowest total, receiving 1.12 inches, or 1.07 inches less than normal.
Despite the drier weather, soil moisture improved in most of the state. Moisture levels at 2 inches increased 16 percent on average in November. Soils were drying for most of the month until rain in the last weekend of the month caused increases of 20 to 50 percent.
Similar increases occurred at the 4- and 8-inch depths, while soil moisture remained stable at depths of 20 inches and greater.
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 U.S. Geological Survey (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 the 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.)
Mean provisional flow aggregated statewide, using the available monthly mean data shown this month in Table 2, was below the median value for November (approximately 70 percent of the median) and below the mean for November (approximately 40 percent of the mean). Monthly mean discharge values in November ranged mostly from below normal to normal. Mean streamflow in the Rock River and the Pecatonica River in northwestern Illinois was above normal.
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 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 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-October water levels at 20 reservoirs for which levels were reported last month and this month, reported end-of-November water levels were lower at 10 reservoirs, higher at 6 reservoirs, and about the same as at the end of October at 4 reservoirs. For the 20 reservoirs with measurements reported at the end of November, water levels were below the normal target pool or spillway level at 17 reservoirs, and at or above the normal target pool or spillway level at 3 reservoirs. Note: The normal target levels at some reservoirs decrease in December.
Major Reservoirs. At the end of November, the water levels at Lake Shelbyville and Carlyle Lake were about the same as at the end of October, and the water level at Rend Lake was 0.4 feet lower than at the end of October. At the end of November, Lake Shelbyville was 0.9 feet below the December 1 target level, Carlyle Lake was 0.2 feet below the December 1 target level, and Rend Lake was 0.2 feet below 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 November 2022 mean level for Lake Michigan was 579.3 feet. The monthly mean level one year ago (November 2021) was 580.0 feet. The long-term average lake level for November is 578.8 feet, based on 1918–2021 data. In this period of record, the lowest mean level for Lake Michigan for November occurred in 1964 at 576.3 feet, and the highest mean level for November occurred in 1986 at 582.0 feet. The month-end level of Lake Michigan was 579.0 feet. All values are provided by the U.S. Army Corps of Engineers Detroit District.
Groundwater Information (Jennie Atkins)
Water tables declined slightly in November, averaging 0.3 feet below October levels (Table 4). Seventeen of the 24 monitored wells reported lower levels at the end of the month, most having declines of 0.5 feet or less. However, the Perry well (Pike County) declined 1.9 feet in November to an end of month reading of 10.5 feet, 7.0 feet lower than in November 2021 but 0.8 feet higher than the 15-year average.
Well levels averaged 2.5 feet below last year’s levels. Besides Perry, several other wells including both Bondville wells (Champaign County) and the Carbondale well (Jackson County) ended the month 5 feet or more below the November 2021 level. Good Hope (McDonough County) dropped 0.7 feet to 13.1 feet, or 7.1 feet below last year’s reading.
Wells averaged 2.3 feet below the 15-year average and 1.9 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
