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May Precipitation Highlights:

  • Monthly rainfall was 1-2" above normal for most of central IL, but up to 1-2" below normal for east central and southeast IL.  While severe weather was not as active as a typical May, a couple of significant weather events occurred.
    • May 14-15: A cold front triggered strong thunderstorms across the Illinois River Valley from the late evening of May 14th into the early morning hours of May 15th.  Scattered wind damage occurred across portions of Knox and Peoria counties, with power poles down in Galesburg and Abingdon and a large tree falling onto a house in Brimfield in Peoria County.  The storms weakened considerably as they pushed further southeast across the remainder of central Illinois.  Rainfall with this system was heaviest northwest of the Illinois River, where amounts in excess of 2 inches occurred across Knox County.  Amounts decreased substantially further southeast, with many locations across east-central and southeast Illinois picking up less than a half inch.
       
    • May 25: An upper level low pressure system cut-off from the main jet stream, slowly pivoted eastward across the Plains.  Southeast flow ahead of this system brought ample Gulf of Mexico moisture northward into the region.  Numerous small scale boundaries served as the primary focus for scattered thunderstorm development during the afternoon and evening.  Due to very weak steering currents aloft, the thunderstorm cells tracked northward at 25-35 mph, allowing some of them to drop locally heavy rainfall in a short amount of time.  A few of the cells also produced damaging wind gusts of 50-60 mph and brief funnel clouds.  Rainfall was highly variable across the area.  The heaviest rainfall was focused across Peoria County where a number of cells merged and re-formed, dumping as much as 2.50" and creating flash flooding in the Peoria metro.  

 

 

May Temperature Highlights:

  • Monthly average temperatures were a few degrees below normal across all of central and southeast IL. The first half of the month saw much below normal temperatures.  A late season freeze occurred on May 9th, when most areas dropped into the upper 20s to lower 30s.  The last half of the month saw warmer temperatures with the hottest stretch occurring on the 23rd-25th, when widespread mid to upper 80s highs were common.
     

 

Climate Statistics:
 

Site

Precipitation
 

Departure from Normal Average Temperature
 
Departure from Normal

Charleston

4.58" +0.39" 61.4 -2.3
Danville 4.81" +0.23" 61.1 -1.9
Decatur 6.34" +1.90" 60.3 -3.7
Effingham

3.89"

-1.38" 62.4 -1.0

Flora

4.50" -0.45" 61.9 -2.3
Galesburg 6.11" +1.66" 58.8 -2.6

Havana

4.29" -0.18" N/A N/A

Jacksonville

6.11" +1.30" 60.9 -1.2

Lincoln

4.80" +0.64" 60.8 -2.2

Normal

5.69" +1.05" 60.4 -0.7

Olney

3.99" -1.67" 61.2 -2.4

Paris

3.20" -1.35" 58.5 -4.5

Peoria

5.15" +0.82" 60.2 -2.2
Springfield

5.88"

+1.64" 61.4 -2.3

Tuscola

4.54" +0.36" 60.6 -2.6
Urbana 4.09" -0.50" 59.5 -2.7


The following links are the monthly climate summaries for area cities. Only the summaries for Peoria, Springfield, and Lincoln are considered "official", meaning they are the station of record for their respective locations. The other summaries are "supplemental", meaning another location in the area is the official climate station for the city.

  • Peoria -- Peoria International Airport
  • Springfield -- Abraham Lincoln Capital Airport
  • Lincoln -- National Weather Service Office
  • Champaign -- University of Illinois-Willard Airport
  • Decatur -- Decatur Airport
  • Lawrenceville -- Lawrenceville-Vincennes International Airport
  • Mattoon -- Coles County Memorial Airport

Climate data for other cities is available at http://w2.weather.gov/climate/xmacis.php?wfo=ilx
 

June Look Ahead:

  • Official outlooks from NOAA's Climate Predication center show above normal temperatures favored for the area, and a trend towards below normal rainfall.

 

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Spring Season Overview

  • March through May saw above normal precipitation for most of central and southeast IL.  Rainfall surpluses of 2-4 inches were common across the central part of the state.  
  • Snowfall was a couple inches above normal north of a Havana to Bloomington line.  Little to no snow fell over east central and southeast IL.
  • Seasonal temperatures were near to slightly below normal across the area.

Spring Season: Precipitation, Snowfall, Temperature, and Departure from Normal Maps

 

 

 

  
Links below are the seasonal climate summaries for area cities. Only the summaries for Peoria, Springfield and Lincoln are considered "official", meaning they are the station of record for their respective locations. The other summaries are "supplemental", meaning another location in the area is the official climate station for that city.

  • Peoria -- Peoria International Airport
  • Springfield -- Abraham Lincoln Capital Airport
  • Lincoln -- Lincoln NWS office
  • Champaign -- University of Illinois - Willard Airport
  • Decatur -- Decatur Airport
  • Lawrenceville -- Lawrenceville-Vincennes International Airport
  • Mattoon -- Coles County Airport

Climate data for other area cities is available at http://www.nws.noaa.gov/climate/xmacis.php?wfo=ilx