National Weather Service United States Department of Commerce

Key Points:

  • Monthly rainfall was well above normal east of I-57, and northwest of the Illinois River.  The highest surpluses were south of I-70, where some locations were more than 6" above normal.  These much wetter than normal conditions were the result of rainfall associated with the remnants of Tropical Storm Gordon, on the 6th-8th.  A few locations in far southeast IL reported 8-10" of rain from this single event.  Besides this event, heavy rain during the early morning hours of the 25th produced 1-3" totals for parts of east central Illinois.  Otherwise, much of the month was dry with little in the way of severe weather.
     
  • Temperatures were well above normal across the region this month.  A  predominant southwest flow kept unseasonably warm air around for much of the month, and prevented Canadian air from sinking south.  Notable stretches of highs in the 90s occurred on the 1st-5th, and again on the 14th-20th.  This combined with the lack of cools spells resulted in monthly average temperatures 3-6 degrees above normal.  This put some sites near their top 10 warmest Septembers.
     

Precipitation, Temperature, and Departure from Normal Maps:

 

 

 

Climate Data:

Site

Precipitation
 

Departure from Normal Average Temperature
 
Departure from Normal

Charleston

N/A N/A N/A N/A
Danville

6.85"

+3.92" 71.2 +4.5
Decatur

3.62"

+0.48" 71.1 +3.3
Effingham

5.09"

+2.10" 73.3 +6.1

Flora

6.73" +3.59" 72.8 +5.0
Galesburg

7.30"

+3.83" 68.1 +3.4

Havana

3.27" +0.12" N/A N/A

Jacksonville

3.19" -0.49" 71.4 +4.1
Lincoln 2.29" -0.92" 69.8 +3.9

Normal

2.01"

-1.13" 69.3 +4.2

Olney

7.53" +4.46" 72.5 +4.7

Paris

6.73" +3.55" 69.4 +2.9
Peoria 2.76" -0.39" 70.6 +4.5
Springfield

3.21"

+0.31" 72.2 +5.4

Tuscola

4.52" +1.51" 71.0 +4.6
Urbana

4.72"

+1.59" 71.2 +5.0

 

Links below 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 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