Rains and Hot Weather Continue in Illinois

The wetter and warmer than normal weather continued in Illinois this week. For the period of June 16-22, the state average temperature was 76.8 degrees, 3.6 degrees above normal. Meanwhile the statewide average precipitation was 2.46 inches, 1.55 inches above normal.
Illinois already experienced above normal temperature and precipitation in the first half of June. Combined with this week’s weather, the statewide average temperature for June so far is 74.5 degrees, 3.4 degrees above normal. The statewide average precipitation at this point is 6.35 inches, 3.37 inches above normal.
If you are thinking that we must be closing in on a record, you are correct. Statewide this is already the 10th wettest June on record. The wettest June on record is 1902 with 8.37 inches. Several individual station records will be set as well. For example, Galesburg has already received 11.25 inches this month. This handily beat the old June record of 9.97 inches set in 1974. This is impressive given that their records go back to 1927.
The wettest areas of the state are western Illinois and east-central Illinois. Based on radar estimates and reports from weather observers, monthly totals of 9 inches or more were common in these areas. The wettest spot so far is Warsaw (Hancock County CoCoRaHS observer) which has reported 11.38 inches through today (June 22) with more rain falling after the regular reporting time.
Here are the precipitation and precipitation departure maps for June 1-22, 2010, for Illinois.

June 1-22, 2010 rainfall in Illinois
The June 1-22, 2010, rainfall in Illinois. Map courtesy of the NOAA Midwestern Regional Climate Center.

June 1-22, 2010 rainfall departure for Illinois
The June 1-22, 2010, rainfall departures from normal in Illinois. Map courtesy of the NOAA Midwestern Regional Climate Center.

First Half of June – Warm and Wet

Based on preliminary data, the statewide average temperature for the first half of June was 73.4 degrees, 3.3 degrees above normal.
The statewide average rainfall for the first half of June was 3.85 inches, 1.78 inches above normal. Much of the southern and northern thirds of the state were near normal while central Illinois was much above normal.
The wettest areas are in a region between Quincy and the Quad Cities (again) and in east-central Illinois. For June 1-15, the following rainfall totals were reported: Moline with 4.35 inches, Quincy with 4.78 inches, Springfield with 3.85 inches, Champaign with 4.88 inches , and a CoCoRaHS observer in Sidney (SE of Champaign) with 7.84 inches.
The National Weather Service provides a high-resolution precipitation product that combines both rain gauge and radar data. It can be found at http://water.weather.gov/precip/. Here is the rainfall departure map for June 1-15, 2010, clearly showing the heavy rain areas in western and east-central Illinois.
More rains are falling in Illinois while this is being written on the afternoon of June 15.

June 1-15, 2010 radar image
The NWS precipitation departure for the period June 1-15, 2010, centered on Illinois (click to enlarge).

June 5 Tornado Outbreak in Illinois

A large tornado outbreak occurred in Illinois on June 5. The NOAA Storm Prediction Center has 31 preliminary damage reports for the state (see below). In some cases a single tornado generated multiple damage reports  as it moves cross-country. At this time there appears to have been 15 confirmed tornadoes involved.
NWS offices conducted extensive damage surveys in central and northern Illinois the next day. Here are their findings:

  1. Seven confirmed tornadoes in central Illinois (Lincoln NWS office)
  2. One confirmed tornado in northwest Illinois (Davenport NWS office)
  3. Seven confirmed tornadoes in northeastern Illinois (Chicago NWS office)
SPC storm reports for June 5, 2010
NOAA Storm Prediction Center storm damage reports for June 5, 2010 (click to enlarge).
Time Location County State Lat Lon Comments
0035 3 NE ABINGDON KNOX IL 4083 9036 BRIEF TOUCHDOWN. NO DAMAGE REPORTED AT THIS TIME.(ILX)
0103 YATES CITY KNOX IL 4078 9001 POWER LINES DOWN. (ILX)
0106 ELMWOOD PEORIA IL 4078 8997 TORNADO ENTERING ELMWOOD. NO DAMAGE REPORTS AT THIS TIME. (ILX)
0110 1 E HENRY PUTNAM IL 4111 8934 FIRST TOUCHDOWN OF TORNADO AT EDGE OF SAWMILL LAKE.(DVN)
0114 2 S BRIMFIELD PEORIA IL 4081 8988 TORNADO JUST SOUTH OF ROUTE 8. (ILX)
0120 7 E HENRY PUTNAM IL 4111 8923 RELAYED VIA LINCOLN NWS(DVN)
0125 PEORIA PEORIA IL 4074 8961 TORNADO 4 MILES NORTHWEST OF THE PEORIA AIRPORT.(ILX)
0130 PEORIA PEORIA IL 4074 8961 TORNADO AT ROUTE 150 AND INTERSTATE 74. (ILX)
0130 3 W LOSTANT LA SALLE IL 4114 8912 HOMES BADLY DAMAGED AND TREES DOWN. (LOT)
0131 7 W PEORIA PEORIA IL 4074 8974 TORNADO AT HWY 116. (ILX)
0133 MAGNOLIA PUTNAM IL 4111 8920 REPORTED BETWEEN MAGNOLIA AND MC NABB MOVING EAST(DVN)
0141 2 S LOSTANT LA SALLE IL 4111 8906 NEAR INTERSECTION OF RT 18 AND INTERSTATE 39. (LOT)
0143 EAST PEORIA TAZEWELL IL 4067 8955 TORNADO AT ROUTE 24 NEAR THE ILLINOIS RIVER. (ILX)
0145 2 W STREATOR LA SALLE IL 4113 8887 NO SIGHTING OF TORNADO BUT DAMAGE SEEN. BARNS AND SILOS BLOWN OVER. DAMAGE TO ROOFS. SHEET METAL WRAPPED AROUND POLES. (LOT)
0150 STREATOR LA SALLE IL 4113 8883 2 TORNADOES ON THE GROUND. ONE WAS DUE WEST OF STREATOR. THE OTHER WAS 1 MILES WEST OF STREATOR AND WAS REPORTED 50 FEET WIDE.(LOT)
0153 2 S GERMANTOWN HILLS TAZEWELL IL 4074 8947 TORNADO AT ROUTE 116 JUST SOUTH OF ISP. (ILX)
0159 6 E STREATOR LA SALLE IL 4113 8872 (LOT)
0211 STREATOR LA SALLE IL 4113 8883 HEAVY DAMAGE IN STREATOR. PEOPLE TRAPPED IN HOMES AND TELEPHONE OUTAGES. (LOT)
0218 8 W DWIGHT LIVINGSTON IL 4110 8858 2 MILES E OF RT 170 ALONG RT. 17 (LOT)
0226 DWIGHT LIVINGSTON IL 4110 8842 STATE POLICE CONFIRMED TORNADO JUST WEST OF INTERSTATE 55 AND SOUTH OF RT. 17 (LOT)
0234 3 E DWIGHT LIVINGSTON IL 4110 8837 ILLINOIS STATE POLICE ARE FOLLOWING A TORNADO ON THE GROUND 3 MILES EAST OF DWIGHT AND 1 MILE SOUTH OF STATE HIGHWAY 17. (LOT)
0239 DWIGHT LIVINGSTON IL 4110 8842 HEAVY DAMAGE SOUTH PART OF TOWN. REPORTED BY FIRE DEPARTMENT (LOT)
0247 1 NW BUCKINGHAM KANKAKEE IL 4106 8819 17000W AND RT 115. TORNADO JUST DISSIPATED (LOT)
0256 LOSTANT LA SALLE IL 4114 8906 DELAYED REPORT. ON I-39 JUST SOUTH OF LOSTANT … SEMIS BLOWN OFF I-39 EAST INTO CORNFIELD. SEMIS WERE ESTIMATED AT SEVERAL HUNDRED FEET INTO CORNFIELD. (LOT)
0301 2 E HERSCHER KANKAKEE IL 4105 8806 ON RT 115. SPOTTER REPORTS TORNADO KEEPS TOUCHING DOWN AND LIFTING. (LOT)
0309 6 NE FAIRBURY LIVINGSTON IL 4080 8843 CORN WAS TWISTED IN A FIELD AND VENTS WERE TORN OFF A BARN ROOF. (LOT)
0313 5 SW CULLOM LIVINGSTON IL 4084 8834 (LOT)
0315 1 SE HOPEDALE TAZEWELL IL 4041 8940 TORNADO AT HOPEDALE ROAD AND OLYMPIA ROAD MOVING EAST. (ILX)
0323 2 N ST. ANNE KANKAKEE IL 4105 8772 2 TORNADOS ON GROUND. (LOT)
0355 ST. ANNE KANKAKEE IL 4102 8772 HOUSE DESTROYED AT INTERSECTION 3795S AND 6000E (LOT)
0400 2 SW BEASON LOGAN IL 4013 8923 TWO HOMES SUSTAINED MAJOR DAMAGE. (ILX)

Fourth Warmest Spring in Illinois

Based on preliminary data, the statewide average temperature for spring in Illinois was 55.3 degrees, 3.3 degrees above normal and the fourth warmest spring on record. Warmer than normal conditions prevailed in the spring months of March (+2.5 degrees), April (+6.2 degrees), and May (+1.3 degrees).
The statewide average precipitation for spring was 11.97 inches, just 0.7 inches above normal. This is notably less than the 15.83 inches that fell in the spring of 2009 and the 14.21 inches that fell in the spring of 2008.
Climatologists and meteorologists tend to use the calendar months of March-May to define spring and not the astronomical definition from the vernal equinox (usually March 20) to the summer solstice (usually June 21). The calendar months better match the climate of Illinois. Our winter weather usually diminishes by early to mid March across much of Illinois and summer weather usually arrives long before June 21.

Spring temperatures in Midwest.
Spring temperature departures for the Midwest for 2010.

Spring precipitation in the Midwest
Spring precipitation in the Midwest for 2010.