Soil temperatures at depths of 4 inches under
sod averaged 77.7 degrees in Illinois on June 14, 4.7 degrees
above the long-term average. Temperatures have risen an average
of 8.4 degrees the first two weeks of the month.
Temperatures have been warmer under bare soil. At 4 inches,
temperatures averaged 82.5 degrees on June 14, 9.2 degrees above
normal. Daily highs were in the mid- to high 90s for most of the
Although soil temperatures have been rising, soil moisture
levels have been declining. The first half of June has been dry,
receiving 0.29 inches of precipitation, or 1.60 inches less than
normal. This, in conjunction with the warm soils, has led to
declining soil moisture across the state.
Levels at the 2-inch depths have decreased 25 percent between
June 1 and 14 to an average of 0.21 water fraction by volume (wfv).
Soil moisture increased in central Illinois on June 14 as storms
moved through the area, but levels remain below the historical
Similar declines occurred at the 4-, 8-, and 20-inch depths.
However, soil moisture remains high at 39 and 59 inches with no
The Illinois State Water Survey’s WARM Program collects hourly
and daily weather and soil information at 19 stations across the
state. Daily and monthly summaries can be found at the WARM
http://www.isws. illinois.edu/warm/ and in the Illinois
Water and Climate Summary
[Lisa A. Sheppard]
The Illinois State Water Survey at the University of Illinois at
Urbana-Champaign, a division of the Prairie Research Institute, is
the primary agency in Illinois concerned with water and atmospheric