Warmer weather in the second week of April brought warmer and drier soils, according to Jennie Atkins, a manager for the Water and Atmospheric Resources Monitoring Program at the Illinois State Water Survey.
Bare soil temperatures, on average, rose more than 15 degrees during the week with statewide averages of 63 F for 2-inch depths and 61.5 degrees for 4 inches on April 16. Temperatures under sod rose more slowly, with temperatures at the end of the week averaging 57 and 55.2 degrees at 4- and 8-inch depths, respectively.
Increases occurred across the state. Temperatures in southern Illinois rose 15.2 degrees, ending the week with a regional average of 63.7 degrees at 2 inches under bare soil. The coolest temperatures were in the north, where 2-inch temperatures averaged 60.1 degrees April 16.
Soil moisture levels decreased slightly with the warmer weather. Levels at a depth of 2 inches declined 13 percent, on average, the second week of April to a statewide average of 0.31 water fraction by volume. Levels at 4 inches also decreased to 0.32 wfv. No significant changes occurred at depths of 8 inches and greater, as levels remained near or above field capacity for most of the soils monitored.
The program collects hourly and daily weather and soil information at 19 stations across the state. Daily and monthly summaries can be found at the program’s website and in the Illinois Water and Climate Summary.