ILLINOIS WATER AND CLIMATE SUMMARY

Transcription

1 ILLINOIS WATER AND CLIMATE SUMMARY December 2013 DECEMBER 2013 OVERVIEW Temperatures and precipitation were below the long-term average in Illinois during December. Mean streamflow statewide was about equal to the median for the month, but varied by region. Shallow groundwater levels were below long-term average depths. Temperatures averaged 25.8 F in December, 4.1 below the longterm average (Figure 1). Temperatures in the crop reporting districts (CRDs) ranged from 18.8 in the northwestern district to 32.7 in the southeastern district. Precipitation averaged 2.63 inches over the month, 0.06 inches below the long-term average (Figure 1). Precipitation was greatest in the southeastern crop reporting district with 7.03 inches. The northwestern and western districts saw the least amount of rain, averaging 1.22 inches. Mean provisional streamflow aggregated statewide was about equal to the median flow in December (Figure 1). Monthly mean discharge values varied considerably by location, ranging from much below normal to much above normal. Water surface levels at the end of December were below full pool/ target operating levels at 15 of 21 reporting reservoirs. At the end of December, Carlyle Lake was 2.3 feet above at its winter target level, Lake Shelbyville was 6.0 feet above its nominal January 1 target level (0.3 feet above December 1 target level), and Rend Lake was 3.1 feet above the spillway level. Lake Michigan remains below its long-term mean level. Shallow groundwater levels statewide were below normal this month with an average departure of -1.4 feet. No departure this month was observed from the deviation in normal groundwater levels between November and December (Figure 1). Levels averaged 0.6 feet above November levels and were approximately 1.6 feet above December levels of last year. Figure 1 Statewide departures from normal Water and Atmospheric Resources Monitoring Program Contact Jennie R. Atkins: (217) , jatkins@illinois.edu

2 WEATHER/CLIMATE INFORMATION Jim Angel and Jennie Atkins The following description of precipitation, temperature, and snowfall (in winter) comes from data compiled by a number of networks that report to the National Oceanic and Atmospheric Administration (NOAA). There are over 250 reporting sites in Illinois alone. These data are provisional and may change slightly over time. Temperatures averaged 25.8 F statewide in December, 4.1 below the month s long-term average. The coldest temperatures were measured in northwestern Illinois with average temperatures ranging from 15 to 20 F. A minimum temperature of -19 F was measured on December 25 at the Elizabeth, IL station. Precipitation in December was near the long-term statewide average of 2.63 inches. Conditions were dry across northern and central Illinois during the month though much wetter in the southern portion of the state with rainfall totals greater than 6 inches. Snow fell throughout the state in December. Northern Illinois as well as portions of southern Illinois received between 10 and 15 inches for the month. Galena, in northwestern Illinois, reported 14 inches of snow for December with 5 inches falling on December 22 alone. Drought conditions persisted in the state. On December 31, the U.S. Drought Monitor placed 22 percent of the state in moderate or severe drought. Twenty-eight percent of the state was considered abnormally dry, a significant decrease from the 45 percent on November 26. ILLINOIS CLIMATE NETWORK (ICN) Jennie Atkins The Illinois Climate Network (ICN) consists of 19 stations across the state which collect hourly weather and soil information. Data for December are presented in Table 1. Wind speeds averaged 7.0 mph in December, a slight decrease from November. Station averages ranged from 4.4 mph at Kilbourne to 11.2 mph at Bondville. The highest wind gust, 35.4 mph, was measured at the DeKalb station on December 4. Air temperatures averaged 27.2 F across the network, 4.1 lower than the long-term network average for December and 11.4 lower than November. The highest temperature, 69.6 F, was measured at Dixon Springs on December 4. The lowest temperature was F, measured at Freeport on December 24. Soil temperatures continued to decline in December. Soil temperatures averaged 37.9 F at 4 inches under bare soil, 40.1 F at 4 inches under sod, and 40.8 F at 8 inches under sod at the network s southern stations. At the central stations, soil temperatures averaged 32.0 F at 4 inches under bare soil, 35.2 F at 4 inches under sod, and 34.2 F at 8 inches under sod. Temperatures averaged 32.0 F at 4 inches under bare soil, 34.6 F at 4 inches under sod, and 34.6 F at 8 inches under sod at the northern stations. Precipitation totals averaged 3.14 inches across the network, 0.73 above December s long-term average. The largest totals were measured in southern Illinois where 9.69 inches was measured at the Dixon Springs station. The lowest total, 0.90 inches, was measured at Monmouth. Hourly and daily weather and soil data for all ICN stations are available on the WARM website at isws.illinois.edu/warm/soiltemp.asp. Soil moisture graphs have been removed from the summary until next spring. For more information or data requests, please contact WARM Program Manager Jennie Atkins. 2

3 Figure 2 Illinois precipitation and precipitation departure from average for December

4 Figure 3 Illinois precipitation and precipitation departure from average for year to date (top), last 6 months (middle), and last 3 months (bottom) 4

5 Table 1. Data from the Illinois Climate Network (ICN), December 2013 Station Ave Wind Speed (mph) Ave Wind Direction ( ) Maximum Wind Gust (mph) Maximum Air Temperature Minimum Air Temperature Average Air Temperature Freeport Big Bend St Charles DeKalb Belleville Big Bend Bondville Brownstown Carbondale Champaign DeKalb Dixon Springs Fairfield Freeport Kilbourne 4.4M 204.2M 24.8M Monmouth Olney Peoria 6.0M 187.9M 28.7M Perry (Orr) 5.9M 204.0M 26.8M Rend Lake (Ina) Springfield St. Charles Stelle Monmouth Perry Kilbourne Springfield Belleville Peoria Brownstown Stelle Champaign Bondville Fairfield Rend Lake Olney Carbondale Dixon Springs Table 1 continued Station Total Solar Radiation (MJ/m 2 ) Average Relative Humidity (%) Total Precipitation (in) Average Dew Point Total Potential Evapotranspiration (in) Ave Soil Temperature at 4" under Sod Ave Soil Temperature at 8" under Sod Ave Soil Temperature at 4" under Bare Soil Belleville Big Bend Bondville Brownstown Carbondale Champaign DeKalb Dixon Springs Fairfield Freeport Kilbourne Monmouth Olney Peoria Perry (Orr) Rend Lake (Ina) Springfield St. Charles Stelle Notes: M = Missing data. 5

6 SURFACE WATER INFORMATION Bill Saylor and Amy Russell 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, the Illinois State Water Survey (ISWS), and the USACE. Provisional discharge data are obtained from the USGS. Table 2 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. Peak stage is represented here by morning readings posted daily by the USACE or the National Weather Service. Flood stage is defined locally for each gage location. The Illinois River and the Mississippi River remained below local flood stages in December at Illinois locations. The Ohio River reached local flood stage at a few locations in December. Provisional monthly mean flows for 26 streamgaging stations located throughout Illinois are shown in Table 3. 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 3 was determined by ranking the December 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 3 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 3 contribute to their flow.) Mean provisional flow aggregated statewide was about equal to the median value for December (approximately 100 percent of the median) and below the long-term mean for the month (about 65 percent of the mean). However, monthly mean streamflow conditions differed considerably by location. Central Illinois streams were primarily in the much below normal to below normal range for December. Monthly mean streamflow in southern Illinois was above normal to much above normal, boosted by a significant precipitation event on December La Moine River at Ripley monthly discharge is again listed as not available for this month in Table 3 based on October field measurements significantly lower than posted values. Water-Supply Lakes and Major Reservoirs. Table 4 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 4), 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-november water levels at 21 reservoirs for which levels were reported last month and this month, reported end-of-december water levels were lower at six reservoirs, higher at 12 reservoirs, and about the same as at the end of last month at three reservoirs. For the 21 reservoirs with measurements reported at the end of December, water levels were below normal target pool or spillway level at 15 reservoirs, at about full pool level at two reservoirs, and above seasonal target pool levels at four reservoirs. Major Reservoirs. Compared to water levels at the end of November, at the end of December, Carlyle Lake was 0.1 foot higher, Lake Shelbyville was 0.4 feet higher, and Rend Lake water level was 2.6 feet higher. At the end of December, Carlyle Lake was 2.3 feet above at its winter target level, Lake Shelbyville was 6.0 feet above nominal January 1 target level (0.3 feet above December 1 target level), and Rend Lake was 3.1 feet above spillway level. Great Lakes. Current month mean and endof-month values are provisional and are relative to International Great Lakes Datum The December 2013 mean level for Lake Michigan was feet. The monthly mean level one year ago (December 2012) was feet. The long-term average lake level for December is feet, based on data. In this period of record, the lowest mean level for Lake Michigan in December occurred in 2012 at feet, and the highest level for December occurred in 1986 at feet. The month-end level of Lake Michigan was feet. All values are provided by the U.S. Army Corps of Engineers Detroit District. 6

7 Table 2. Peak Stages for Major Rivers during December 2013 River Station River mile* Flood stage (feet)* Peak stage (feet)** Date Illinois Morris La Salle Peoria Havana Beardstown Hardin Mississippi Dubuque Keokuk Quincy Grafton St. Louis Chester Thebes Ohio Cairo 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. Table 3. Provisional Mean Flows, December 2013 Station Drainage area (sq mi) Years of record 2013 mean flow (cfs) Long-term flows Mean* Median (cfs) (cfs) Flow condition Percent chance of exceedence Days of data this month Rock River at Rockton normal Rock River near Joslin normal Pecatonica River at Freeport normal Green River near Geneseo below normal Edwards River near New Boston N/A N/A N/A 10 Kankakee River at Momence above normal Iroquois River near Chebanse normal Fox River at Dayton normal Vermilion River at Pontiac below normal Spoon River at Seville below normal LaMoine River at Ripley N/A N/A N/A N/A Bear Creek near Marceline below normal Mackinaw River near Congerville N/A N/A N/A 18 Salt Creek near Greenview below normal Sangamon River at Monticello below normal South Fork Sangamon near Rochester much below normal Illinois River at Valley City 26, ,540 15,396 below normal Macoupin Creek near Kane below normal Vermilion River near Danville below normal Kaskaskia River at Vandalia much below normal Shoal Creek near Breese normal Embarras River at Ste. Marie normal Skillet Fork at Wayne City above normal Little Wabash below Clay City above normal Big Muddy at Plumfield above normal Cache River at Forman much above normal 4 31 Notes: Source streamflow data are obtained from the U.S. Geological Survey. N/A = not available (due to ice or equipment problems). Much below normal flow = % 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

8 Table 4. Reservoir Levels in Illinois, December 2013 Normal pool Current level Monthly Average difference Years November or target difference from normal change from normal of reported pumpage Reservoir County level (feet) or target (feet) (feet) or target (feet) record (million gallons) Altamont Effingham Bloomington McLean N/A Canton Fulton N/A Carlinville Macoupin Carlyle (1) Clinton N/A Coulterville Randolph N/A N/A N/A Decatur (1,3) Macon Evergreen (4) Woodford N/A Glenn Shoals (2) Montgomery w/hillsboro Greenfield Greene N/A N/A N/A Highland Madison Hillsboro (2) Montgomery Jacksonville (2) Morgan N/A N/A w/mauvaise Terre Kinkaid Jackson Lake of Egypt Williamson N/A N/A N/A Mattoon Coles N/A N/A w/paradise Mauvaise Terre (2) Morgan N/A N/A no meter Mt. Olive (new) Macoupin N/A N/A w/mt. Olive (old) Mt. Olive (old) Macoupin Nashville (3) Washington N/A N/A N/A Pana Christian N/A Paradise Coles N/A N/A Paris (east) Edgar N/A N/A Not PWS Paris (west) Edgar N/A N/A w/paris (east) Pinckneyville Perry N/A N/A N/A Raccoon (1) Marion N/A N/A Rend Franklin N/A Salem (3) Marion Shelbyville (1) Shelby Not PWS Sparta (3) Randolph N/A Spring (3,4) McDonough N/A N/A Springfield (1,3) Sangamon Taylorville Christian Vermilion (4) Vermilion Notes: Normal pool and target level datum is NGVD 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 January 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. 8

9 GROUNDWATER INFORMATION Ken Hlinka Comparison to Average Levels. Shallow groundwater levels in 11 observation wells, which are remote from pumping centers, were below normal for the month of December. Levels averaged 1.4 feet below and ranged from 5.2 feet below to 3.8 feet above normal levels (Table 6). Comparison to Previous Month. Shallow groundwater levels were above those of the previous month. Levels averaged 0.6 feet above and ranged from 1.2 feet below to 4.3 feet above levels of November. Comparison to Same Month, Previous Year. Shallow groundwater levels in December were above levels measured one year ago. Levels averaged 1.6 feet above this month and ranged from 1.5 feet below to 4.5 feet above levels of December Table 5. Month-End Shallow Groundwater Level Data Sites, December 2013 Number Well name County Well depth (feet) This month s reading (depth to water, feet) 15-year avg. level (feet) Deviation from Period of record avg. (feet) Previous month (feet) Previous year (feet) 1 Galena JoDaviess Mt. Morris Ogle Crystal Lake McHenry Cambridge Henry * NA NA NA NA 5 Fermi Lab DuPage NA NA NA NA NA 6 Good Hope McDonough NA NA NA NA NA 7 Snicarte Mason Coffman Pike Greenfield Greene Janesville Coles St. Peter Fayette NA NA NA NA NA 12 SWS #2 St. Clair Boyleston Wayne NA NA NA NA NA 14 Sparta Randolph SE College Saline Bondville Champaign Notes: N/A = Data not available. * Data not used in analysis Averages

10 ADDENDUM Nancy Westcott Imperial Valley. Precipitation for December 2013 was well below average (Figure 5a). Monthly gage totals were largest in the far northern and southwestern portions of the network, and smallest in the central region of the network. Individual gage amounts ranged from 1.61 inches at Site #2 to 0.90 inches at Site #6. The , 30-year average precipitation amounts for December at Havana and Mason City are 2.76 and 2.33 inches, respectively. The December 2013 network average of 1.22 inches is about 64 percent of the 20-year ( ) IVWA December network average of 1.91 inches. Cook County. The December 2013 total precipitation was below average (Figure 5b). Precipitation amounts were greatest in the northwestern and southeastern regions of the network, and least in the west-central area of the network. Precipitation values ranged from 1.76 inches at Site #18 (near S. Halsted Street and W 119th Street) to 1.01 inches at Site #2 (Winnetka). The December 2013 network average of 1.39 inches is about 66 percent of the 24-year ( ) December network average of 2.10 inches. a. Imperial Valley b. Cook County Figure 5 Long-term raingage network precipitation totals (inches) for December 2013 Data sources for information in this publication include the following: CPC - Climate Prediction Center, ISWS - Illinois State Water Survey, MRCC - Midwestern Regional Climate Center, NCDC - National Climatic Data Center, NWS - National Weather Service, USACE - U.S. Army Corps of Engineers, USGS - U.S. Geological Survey, WARM - Water and Atmospheric Resources Monitoring Program, Illinois State Water Survey 2204 Griffith Drive Champaign, IL Tel (217)