Recent rainfalls measure incredible differences          

[June 28, 2007]  CHAMPAIGN -- A high-density rain gauge network identified large differences in rainfall amounts from Monday and Tuesday storms across Champaign County. Amounts ranged from 2.58 inches just west of the Interstate 57-72 interchange, west of Champaign, to less than 0.20 inch in southeast Urbana.

Summer rainfall is highly variable, as individual thunderstorms produce significant rainfall over small areas. For example, one station reported 2.49 inches, while another station three miles to the south reported only 0.16 inch, a 2.33-inch difference. Most rain fell between 10:30 a.m. and noon on Tuesday. Another storm early Wednesday produced another 0.20 to 0.40 inch across parts of Champaign-Urbana.

While official records for Champaign-Urbana date back to 1888 at the Illinois State Water Survey, volunteers in a wider network provide much more detail on such events. The Boneyard Network has operated in the Champaign-Urbana area for years, mainly with data from ISWS employees. That network is merging with the much larger Community Collaborative Rain, Hail and Snow network that covers Champaign County, the rest of Illinois and is part of a rapidly expanding national volunteer network. The map has data mainly from network participants. Data from the two volunteer networks should not be regarded as official, quality-assured ISWS records.

Amounts from both storms exceeded 2.20 inches in southwestern Champaign and north-central Champaign-Urbana, between Springfield Avenue and I-74. At the ISWS, 1.34 inches brought the June total to 4.54 inches, 0.33 inch above normal.

Until this week, "abnormally dry" conditions in Champaign County affected crops, lawns and gardens and put the area on the U.S. Drought Monitor. Recent rains have eased those concerns, however.

[Text from Illinois State Water Survey news release]