ILLINOIS WATER AND CLIMATE SUMMARY November 2009

Illinois State Water Survey

2204 Griffith Drive, Champaign, IL 61820 • Tel (217) 333-2210 • Fax (217) 333-6540

November 2009 Overview (Bob Scott)

Temperatures in Illinois during November were well above average, provisionally tied for the 7th warmest November since 1895, while precipitation was below average. Soil moisture within the top 40 inches of soil was above the long-term statewide average. Mean streamflows were well above median values. Shallow groundwater levels were above long-term average depths. The current high levels observed within all water resources of Illinois is a reflection of the highest statewide December-November precipitation total (53.22 inches) since 1895. Temperatures across Illinois (Figure 1) for November were much above average (a +5.2-degree departure). Crop Reporting District (CRD) temperatures ranged from 5.8 degrees above average (northwest and west) to 4.6 degrees above average (east-southeast and southeast). Precipitation amounts for Illinois in November were below average (Figure 1). The statewide average of 2.60 inches represented a 0.72-inch deficit or 78 percent of average for the month. The southeast CRD received the least amount of rainfall, 1.45 inches (33 percent of average), while the west-southwest CRD recorded the greatest rainfall total with 4.09 inches (121 percent of average). Soil moisture conditions in the 0- to 40-inch (0- to 100-centimeter) layer in Illinois at the end of November were above normal across the state (Figure 1). Mean provisional streamflow statewide was above the median flow in November, 770 percent of median (Figure 1). Rivers throughout most of Illinois recorded monthly mean discharges much above normal for November. The Illinois River, the Mississippi River below the Des Moines River, and the Ohio River at Cairo exceeded local flood stages during the month. The Illinois River was above local flood stages downstream from Havana throughout November. Water surface levels at the end of November were below full pool/target operating level at two of 29 reporting reservoirs. At the end of November, Rend Lake was 2.9 feet above spillway level, Lake Shelbyville was 13.6 feet above its seasonal target level, and Carlyle Lake was 7.7 feet above the December 1 target level. Lake Michigan’s mean level remains below the long-term average. Statewide, shallow groundwater levels were above normal with an average departure of +4.2 feet. Combined with the change in normal monthly groundwater levels between November and December, a 1.1-foot decrease in departures from last month was observed (Figure 1). Levels averaged 0.4 feet lower than October levels and were approximately 3.5 feet above November levels of last year.

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Figure 1. Statewide departures from normal

Note: The WARM Network maps and extended network descriptions appear in the January and July issues. Water and Atmospheric Resources Monitoring Program | www.isws.illinois.edu/warm Illinois State Water Survey | Institute of Natural Resource Sustainability | University of Illinois at Urbana-Champaign Contact Bob Scott: (217) 333-4966, email: [email protected]

Weather/Climate Information (Jim Angel and Bob Scott)

Temperatures across Illinois for November were much above normal (Figure 2 and Table 1). The warmest temperature reported in Illinois for the month was 79° F in Bentley (Hancock County) on November 9. The coldest temperature for the month was 22° F in Normal (McLean County) on November 13. Based on preliminary data, this month tied for the seventh warmest November since 1895, a complete flip from last month, which ranked as the seventh coldest October on record. Precipitation for November was below normal statewide (Figure 2 and Table 1). Perry (Pike County) reported the highest one-day precipitation of 2.84 inches on November 17 and the highest monthly total of 5.47 inches. Based on preliminary data, this was the eighth wettest September–November (three months), third wettest June– November (six months), second wettest January–November (year-to-date) and the wettest December–November (12 months) since 1895. Snowfall for November was limited to areas in northern Illinois. The only measureable snow fell on Thanksgiving Day (November 26). Roscoe, near Rockford, reported 1.5 inches, and Belvidere reported 1.0 inch from this event. Severe weather was not reported in Illinois in November. Illinois Climate Network (ICN) Data. Average daily wind speeds across Illinois for November (Figure 3) ranged from 3.6 mph at Dixon Springs to 10.3 mph at Monmouth. St. Charles reported the highest wind gust for the month, 33 mph on November 16. The prevailing wind direction for the month was southerly to south-southwesterly across the state. Wind speeds in excess of 8 mph during the month varied from 42 hours at Dixon Springs to 467 hours at Monmouth. (November has 720 hours.) Average air temperatures in November ranged from 42° F at Stelle to 50° F across southern Illinois. Solar radiation totals in November continued a seasonal decline, ranging from 185 Mega-Joules per meter squared (MJ/m 2) at Freeport to 291 MJ/m2 at Rend Lake and Dixon Springs. Similarly, potential evapotranspiration observations decreased and varied from 1.5 inches at Freeport to 2.3 inches at Fairfield and Belleville. Soil temperatures in Illinois maximized during November and ranged from 46° F at Big Bend and Freeport to 53° F at Rend Lake (4-inch level) and from 47° F across northern Illinois to nearly 57° F at Rend Lake (8-inch level).

   



    







Figure 2. Illinois temperature and precipitation during November 2009

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Table 1. Illinois Precipitation (inches) and Temperature (ºF) by Crop Reporting District Crop Reporting District

Last Month Nov 09 % Temp Amount Avg Dev

Last 3 Months Sep 09% Temp Nov 09 Avg Dev

Last 6 Months Jun 09% Temp Nov 09 Avg Dev

Last 12 Months Dec 08% Temp Nov 09 Avg Dev

Northwest 1.77 69 5.8 10.35 119 0.2 29.88 141 -1.6 52.83 Northeast 1.56 54 5.2 9.84 109 0.1 24.10 115 -1.5 48.88 West 3.36 117 5.8 13.74 146 -0.5 31.32 149 -1.8 55.55 Central 3.20 108 5.1 14.06 156 -0.4 29.16 142 -1.6 53.95 East 2.92 95 5.0 12.56 141 0.2 26.12 125 -1.1 50.02 West-southwest 4.09 121 5.4 18.47 200 -0.5 32.01 161 -1.5 53.67 East-southeast 2.67 69 4.6 14.12 142 -0.1 27.02 126 -1.0 53.28 Southwest 2.00 47 4.8 16.42 156 0.1 31.21 145 -0.7 56.09 Southeast 1.45 33 4.6 15.01 145 0.3 30.10 141 -0.5 56.00 State Average 2.60 78 5.2 13.81 147 -0.1 28.94 138 -1.3 53.22 ________________ Note: Data are provisional. Complete, quality-controlled data are available about six months after a given month.

146 133 148 145 133 142 130 131 126 137

-1.8 -1.8 -1.5 -1.5 -1.0 -1.1 -0.7 -0.3 -0.1 -1.1

Extended climate outlooks issued by the U.S. Department of Commerce, National Oceanic and Atmospheric Administration, Climate Prediction Center for December call for a slight chance of below normal temperatures across the state, especially in southeastern Illinois, and equal chances of above, below, and normal precipitation statewide. Outlooks for climatological winter (December–February) call for a slight chance of above normal temperatures in northwestern Illinois and a slight chance of below normal precipitation in southeastern Illinois.

Soil Moisture Information (Bob Scott)

Precipitation in Illinois during November was above average in central Illinois and below average elsewhere. Regardless, due to heavy rain in October, near-surface soil moisture was near normal (Figure 4). In the 0- to 6-inch layer, values ranged from 77 percent of normal at Rend Lake to 121 percent at Springfield. Conditions in the 6to 20-inch layer were more variable and ranged from 84 percent at Springfield to 160 percent at Olney. Soils in deeper layers were generally wet in eastern and western Illinois and drier in central Illinois. Values ranged from 44 percent (Freeport) to 197 percent (Olney) in the 20- to 40-inch layer and from 67 percent (Freeport) to 186 percent (Dixon Springs) in the 40- to 72-inch layer. Overall, soil moisture in Illinois at the end of November continued to be above normal (Figure 1). Compared to conditions at the end of October, soil moisture in Illinois at the end of November generally decreased by a small amount at all sites (Table 2). Soil moisture in the 0- to 6-inch layer decreased by 22 percent at Ina (Rend Lake), but only by 6 percent or less elsewhere. Changes in the 6- to 20-inch layer included a decrease of 14 percent at Freeport and a decrease of 7 percent or less elsewhere. Freeport’s soil moisture decreased by 31 percent in the 20- to 40-inch layer; however, changes elsewhere were less than 6 percent.

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Figure 4. December 1 observed percent-of-normal soil moisture based on 1985-1995 mean

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Table 2. Soil Moisture in Various Layers on December 1, 2009

Location Freeport (NW) DeKalb (NE) Monmouth (W) East Peoria (C) Stelle (E) Champaign (E) Bondville (E) Perry (WSW) Springfield (WSW) Brownstown (ESE) Olney (ESE) Belleville (SW) Carbondale (SW) Ina (SE) Fairfield (SE) Dixon Springs (SE)

Dec 1 0-6 (inches)

Change from Nov 1 (%)

Dec 1 6 - 20 (inches)

Change from Nov 1 (%)

Dec 1 20 - 40 (inches)

Change from Nov 1 (%)

2.2 2.3 2.3 2.3 2.3 2.2 2.2 2.3 2.2 2.2 2.2 2.2 2.3 1.9 2.3 2.3

-3 -2 0 -1 -1 -4 -6 -1 -4 -1 -4 -3 -4 -22 -2 -3

4.6 5.4 5.1 5.1 5.4 5.1 5.4 5.3 5.1 5.3 5.2 5.3 5.2 5.1 5.3 5.4

-14 -2 -1 -4 0 -3 -3 -7 -2 -1 -2 -1 -6 -4 -1 -2

5.3 7.7 7.6 7.4 7.8 7.2 7.9 7.7 7.6 7.4 7.9 8.3 7.8 7.3 7.8 7.9

-31 0 -1 -3 0 -3 1 -6 -1 -6 0 5 -2 -5 -1 -1

Surface Water Information (Bill Saylor and Vern Knapp)

River and stream discharge and stage data are obtained from gaging stations operated by the U.S. Geological Survey (USGS) or the U.S. Army Corps of Engineers (USACE). The USGS gaging station network is supported, in part, by the Illinois Department of Natural Resources Office of Water Resources, Illinois State Water Survey (ISWS), and the USACE. Provisional discharge data are obtained from the USGS. Table 3 lists the provisional peak stage for the current month compared to flood stage at selected streamgaging stations located on the Illinois, Mississippi, and Ohio Rivers. The peak stage is determined from the daily morning readings posted by the National Weather Service and/or the USACE. On these rivers in Illinois, the peak stages for the month of November occurred during the first week of the month, reflecting the heavy precipitation in late October. Along the Illinois River and the Mississippi River below the Des Moines River, these peak stages were above local flood stages. Ohio River stage also peaked above flood stage at Cairo in November. The Illinois River was above local flood stage at gaging stations downstream of the Spoon River (Havana and downstream) throughout November. Provisional monthly mean flows for 26 streamgaging stations located throughout Illinois are shown in Table 4. Mean values posted by the USGS are listed if available; otherwise, daily mean discharge data posted by the USGS are used to estimate the mean flow for the month. Long-term mean flows for each month are published by the USGS. The month’s median flow for each station listed in Table 4 was determined by ranking the November mean flow for each year of record, and selecting the middle value, 50 percent exceedence probability. 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 4 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 4 contribute to their flow.) Mean provisional flow statewide was much above the median value for November (770 percent of the median) and above the long-term mean for the month (approximately 340 percent of the mean). Monthly mean streamflow conditions throughout most of Illinois, as represented by Table 4 stations, were much above normal for November. Monthly mean streamflow values at several central Illinois streamgage locations were the highest or second-highest recorded for the month of November during the respective periods of streamgage record.

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Table 3. Peak Stages for Major Rivers during November 2009 River Illinois

Mississippi

Ohio

Station

River mile*

Flood stage (feet)*

Peak stage (feet)**

Date

Morris La Salle Peoria Havana Beardstown Hardin

263.1 224.7 164.6 119.6 88.6 21.5

16 20 18 14 14 25

16.5 25.4 21.1 20.7 22.9 30.7

01 01 04 06 06 03

Dubuque Keokuk Quincy Grafton St. Louis Chester Thebes

579.9 364.2 327.9 218.0 180.0 109.9 43.7

17 16 17 18 30 27 33

9.9 13.6 19.1 23.9 32.8 34.9 37.4

01 01 01 02 02 03 04

Cairo 2.0 40 41.6 04 ________________ Notes: * River mile and flood stage from River Stages in Illinois: Flood and Damage Data, Illinois Department of Natural Resources, Office of Water Resources, August 2004 (and Addendum, February 2007). ** Peak stage based on daily a.m. readings, not instantaneous peak. Stage data obtained from U.S. Army Corps of Engineers.

Water-Supply Lakes and Major Reservoirs. Table 5 lists reservoirs in Illinois, their normal pool or target water surface elevation, and other data related to observed variations in water surface elevations. Reservoir levels are obtained from a network of cooperating reservoir operators who are contacted each month by ISWS staff for the current water levels. Reservoir levels are reported in terms of their difference from normal pool (or target level). The average of the month-end readings for the period of record is reported in terms of the difference from normal pool or target level (column 6 of Table 5), and the number of years of record for each reservoir also is given (column 7). Most reservoirs serve as public water supplies, with the exceptions noted in the last column. Compared to end-of-October water levels at 28 reservoirs, reported end-of-November water levels were lower at 12 reservoirs, higher at six reservoirs, and the same as at the end of last month at 10 reservoirs. For the 29 reservoirs with observations reported at the end of October, water levels at two reservoirs were below normal pool, six reservoirs were at normal pool or spillway level, and 21 reservoirs were above normal pool or spillway level. Note that some observers do not measure or report lake levels higher than “full pool” (spillway level) during overflow conditions. Major Reservoirs. Compared to water levels at the end of October, at the end of November Lake Shelbyville was 10.2 feet higher, Carlyle Lake level was 0.8 feet higher, and Rend Lake was 1.1 feet lower. At the end of November, Lake Shelbyville was 13.6 feet above the December 1 target level, Carlyle Lake was 7.7 feet above the December 1 target level, and Rend Lake was 2.9 feet above spillway level. Note: In October 2008, the U.S. Army Corps of Engineers modified the seasonal target level of Lake Shelbyville to 599.7 feet National Geodetic Vertical Datum (NGVD) throughout the period May 1 to December 15. The target operating levels during this period each year previously were varied within the range 599.2 feet–600.2 feet NGVD. The Lake Shelbyville target levels reported in the 2009 issues of the Illinois Water and Climate Summary were the superseded target levels (which were within +0.5 foot of the updated summer-fall target level). Readers should note that other operational parameters also affect the control of flow, and thus the lake level, at Lake Shelbyville. Great Lakes. Current month mean and end-of-month values are provisional and are relative to International Great Lakes Datum 1985. The November mean level for Lake Michigan was 578.3 feet, compared to a mean level of 577.4 feet in November 2008. The long-term average lake level for November is 578.7 feet, based on 1918–2008 data. Historically, the lowest mean level for Lake Michigan in November occurred in 1964 at 576.3 feet, and the highest level occurred in 1986 at 582.0 feet. The month-end level of Lake Michigan was 578.3 feet.

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Table 4. Provisional Mean Flows, November 2009 Station

Drainage Years area of (sq mi) record

2009 Long-term flows mean flow Mean* Median (cfs) (cfs) (cfs) Flow condition

Rock River at Rockton 6363 74 6653 3526 3206 above normal Rock River near Joslin 9549 66 11,740 5153 4767 much above normal Pecatonica River at Freeport 1326 90 1685 749 618 much above normal Green River near Geneseo 1003 70 1886 438 318 much above normal Edwards River near New Boston 445 71 746 164 81 much above normal Kankakee River at Momence 2294 91 3059 4731 1216 much above normal Iroquois River near Chebanse 2091 85 2416 994 484 above normal Fox River at Dayton 2642 89 3528 1477 1321 much above normal Vermilion River at Pontiac 579 65 1394 241 64 much above normal Spoon River at Seville 1636 92 3300 597 291 much above normal LaMoine River at Ripley 1293 85 4236 510 188 much above normal Bear Creek near Marceline 349 64 909 154 22 much above normal Mackinaw River near Congerville 767 60 2042 271 64 much above normal 1804 67 6468 784 271 much above normal Salt Creek near Greenview Sangamon River at Monticello 550 96 1691 245 83 much above normal South Fork Sangamon near Rochester 867 59 3641 271 78 much above normal 26,743 70 ~60,000 14,320 11,483 much above normal Illinois River at Valley City Macoupin Creek near Kane 868 80 3894 309 92 much above normal Vermilion River near Danville 1290 87 2908 616 313 much above normal Kaskaskia River at Vandalia 1940 39 2908 952 654 much above normal Shoal Creek near Breese 735 65 2865 301 127 much above normal 1516 95 2602 747 326 much above normal Embarras River at Ste. Marie Skillet Fork at Wayne City 464 89 214 266 70 normal Little Wabash below Clay City 1131 94 1071 589 209 above normal Big Muddy at Plumfield 794 38 1149 412 115 much above normal Cache River at Forman 244 85 207 196 87 normal ________________ Notes: Source streamflow data is obtained from the U.S. Geological Survey. N/A = not available. Much below normal flow = 90-100% chance of exceedence. Below normal flow = 70-90% chance of exceedence. Normal flow = 30-70% chance of exceedence. Above normal flow = 10-30% chance of exceedence. Much above normal flow = 0-10% chance of exceedence. *As reported in U.S. Geological Survey (USGS) Water Resources Data, Illinois, Water Year 2008.

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Percent Days of chance of data this exceedence month 11 4 4 1 7 9 13 7 3 4 2 5 3 3 3 2 1 1 4 7 1 6 31 19 10 37

30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 N/A 30 30 30 30 30 30 30 30 30

Table 5. Reservoir Levels in Illinois, November 2009

Reservoir

County

Current level Normal pool difference from or target normal or target level (feet) (feet)

Monthly change (feet)

Average difference from normal or target (feet)

Years of record

October reported pumpage (million gallons)

Altamont Effingham 582.0 +0.1 0.0 -2.8 26 6.9 Bloomington McLean 719.5 +0.3 -0.2 -4.4 23 No pumpage Canton Fulton 577.5 +0.1 +0.1 -2.6 19 65.3 Carlinville Macoupin 571.1 +0.3 0.0 -1.0 26 24.4 Carlyle(1) Clinton 443.0 +7.7 +0.8 +3.0 31 N/A Coulterville Randolph 515.9 N/A N/A -2.0 11 N/A Macon 612.5 +1.4 -0.5 +0.3 26 961.0 Decatur(1,3) Evergreen(4) Woodford 720.0 +0.2 -0.3 -3.7 19 296.1 Glenn Shoals(2) Montgomery 590.0 +0.3 -0.7 -0.6 15 w/Hillsboro Greenfield Greene 566.2 +1.7 -0.3 -1.3 12 2.5 Highland Madison 500.0 +0.3 0.0 -0.3 21 33.5 Montgomery 589.0 +0.3 +0.3 -0.3 15 30.4 Hillsboro(2) Jacksonville(2) Morgan 644.0 N/A N/A -0.5 10 w/Mauvaise Terre Kinkaid Jackson 420.0 0.0 -1.4 -0.7 21 63.8 Lake of Egypt Williamson 500.0 N/A N/A -0.8 16 N/A Mattoon Coles 632.0 0.0 0.0 -0.8 16 w/Paradise Mauvaise Terre(2) Morgan 588.5 N/A N/A 0.0 13 no meter Mt. Olive (new) Macoupin 600.0 0.0 0.0 -0.4 7 w/Mt. Olive (old) Mt. Olive (old) Macoupin 654.0 0.0 0.0 -0.8 13 6.0 Nashville(3) Washington 503.8 N/A N/A -1.0 24 17.4 Pana Christian 641.6 +0.1 N/A -1.8 25 19.4 Paradise Coles 685.0 0.0 0.0 -0.6 19 65.0 Paris (east) Edgar 660.0 +0.2 +0.1 -1.1 24 41.2 Paris (west) Edgar 660.1 +0.2 +0.1 +0.1 14 w/Paris (east) Pinckneyville Perry 445.0 N/A N/A -1.7 15 19.9 Pittsfield Pike 596.0 +0.5 -0.3 -0.6 21 16.7 Marion 477.0 +0.7 -0.1 N/A N/A 111.6 Raccoon(1) Rend Franklin 405.0 +2.9 -1.1 +0.6 31 N/A Salem(3) Marion 546.5 -0.8 -1.3 -1.0 14 33.7 Shelbyville(1) Shelby 599.7 +13.6 +10.2 +0.9 31 Not PWS Randolph 497.5 -0.5 -0.3 -1.1 13 12.7 Sparta(3) Spring(4) McDonough 654.0 N/A N/A -0.9 26 56.2 Springfield(1,3) Sangamon 559.6 +0.9 -0.1 -1.8 26 621.0 Taylorville Christian 590.0 +0.2 0.0 -1.1 16 55.9 Vermilion(4) Vermilion 581.7 0.0 0.0 -0.4 24 228.9 Virginia Cass 575.0 +0.1 0.0 -0.2 20 Not PWS _______________ Notes: Normal pool and target level datum is NGVD 1929. Current levels reported represent water surface levels at the end of the month, not the monthly average. Average difference from normal or target level is the arithmetic average of reported month-end values for the period of record indicated. Years of record = total number of monthly readings included in month-end average. Total period of record may be longer. Not PWS = not a public water supply. N/A = not available. (1) Target operating level may vary. Seasonal target levels this month represent December 1 values. (2) Instrumentation not available to measure height of water elevation above spillway. (3) Natural inflow can be supplemented by other sources. (4) Normal pool elevations have changed during period of record reported.

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Groundwater Information (Ken Hlinka)

Comparison to Average Levels. Shallow groundwater levels in 16 observation wells, which are remote from pumping centers, were above average for the month. November levels were 4.2 feet above normal and ranged from 0.3 feet to 10.5 feet above normal levels (Table 6). Comparison to Previous Month. Shallow groundwater levels were below those of last month. Levels averaged 0.4 feet below and ranged from 2.0 feet below to 3.5 feet above levels of last month. Comparison to Same Month, Previous Year. Shallow groundwater levels in November were above levels measured one year ago. Levels averaged 3.5 feet above and ranged from 0.8 feet to 8.9 feet higher this month than November 2008.

Table 6. Month-End Shallow Groundwater Level Data Sites, November 2009



Number

Well name

County

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Galena Mt. Morris Crystal Lake Cambridge Fermi Lab Good Hope Snicarte Coffman Greenfield Janesville St. Peter SWS #2 Boyleston Sparta SE College Dixon Springs Bondville

JoDaviess Ogle McHenry Henry DuPage McDonough Mason Pike Greene Cumberland Fayette St. Clair Wayne Randolph Saline Pope Champaign

________________ Notes: * Data not used in analysis N/A - Data not available.

Well depth (feet) 25.00 55.00 18.00 42.00 17.00 30.00 40.30 28.00 20.70 11.00 15.00 80.00 23.00 27.00 10.19 8.63 21.00

This month’s reading (depth to water, feet) 19.15 12.74 3.4 *23.42 4.79 3.32 34.17 2.91 3.78 4.72 1.26 10.51 1.66 3.62 2.02 3.32 2.76 Averages

Addendum (Nancy Westcott)

15-year avg. level (feet)

Deviation from Period of Previous record avg. month (feet) (feet)

Previous year (feet)

+2.09 +7.49 +2.08 N/A +3.41 +5.60 +3.59 +9.67 +11.01 +0.91 +1.91 +3.47 +3.84 +5.00 +4.02 +2.37 +3.41

+2.31 +7.35 +2.22 N/A +2.58 +5.91 +3.40 +9.88 +10.54 +0.73 +1.58 +5.09 +4.22 +5.69 +3.17 +0.28 +2.31

-0.64 -0.96 +0.73 N/A -0.62 -0.09 -0.19 -1.46 +3.50 -0.42 +0.01 -1.40 -0.14 -1.62 +0.42 -1.95 -1.07

+1.05 +4.35 +0.75 N/A +2.98 +3.28 +1.32 +7.56 +8.93 +0.96 +1.63 +3.99 +1.51 +4.67 +6.68 +5.36 +1.22

+4.37

+4.20

-0.37

+3.52

Imperial Valley Precipitation. Precipitation for November 2009 was above average (Figure 5a). Monthly gage totals were greatest in the west-central to southeastern region, and precipitation was lightest in the northeastern portion of the network. Individual gage amounts ranged from 3.94 inches at Site #22 to 2.72 inches at Site #6. The 1971-2000, 30-year average precipitation amounts for November at Havana and Mason City are 3.26 and 2.95 inches, respectively. The November 2009 network average of 3.42 inches is about 129 percent of the 17-year (1992-2008) IVWA November network average of 2.64 inches. Cook County Precipitation. November 2009 precipitation (Figure 5b) was light. The greatest precipitation was found in the southwestern and northeastern regions of the county, and the lightest precipitation was in the northwestern and southeastern portions of the network. Precipitation values ranged from 1.57 inches at Site #2 (Winnetka) to 0.88 inches at Site #19 (Avenue O, near Wolf Lake). The November 2009 network average of 1.30 inches is about 46 percent of the 20-year (1989–2008) November network average of 2.86 inches.

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 0QXGODGT Figure 5. Long-term raingage network precipitation totals (inches) for November 2009

Data sources for information in this publication include the following: CPC - Climate Predication Center, http://www.cpc.ncep.noaa.gov/index.php ISWS - Illinois State Water Survey, http://www.isws.illinois.edu/ MRCC - Midwestern Regional Climate Center, http://mrcc.isws.illinois.edu/ NCDC - National Climate Data Center, http://www.ncdc.noaa.gov/ NWS - National Weather Service, http://www.nws.noaa.gov/ USACE - U.S. Army Corp of Engineers, http://rivergages.com, http://www.lre.usace.army.mil/greatlakes/hh/ USGS - U.S. Geological Survey, http://waterdata.usgs.gov/il/nwis WARM - Water and Atmospheric Resources Monitoring Program, http://www.isws.illinois.edu/warm/

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