After a cooling spell last weekend, soil temperatures are once again rising in Illinois, according to Jennie Atkins, Water and Atmospheric Resources Monitoring Program manager at the Illinois State Water Survey, part of the Prairie Research Institute at Illinois.
Soil temperatures at depths of 4 inches under bare soil have risen 5 degrees from May 1 to a state average of 65 degrees on May 15. Temperatures were running 4 degrees below average but are right at the long-term average for mid-May.
Cooler weather at the end of the second week of the month caused soils temperatures to fall into the 40s and 50s, but air temperatureshave risen this week to daily highs from the 60s to the low 80s.
Soils remain moist but are drying. Moisture levels at 2 inches averaged 0.42 water fraction by volume across Illinois on May 15, 31% higher than the long-term average and 56% higher than in 2018. On average, levels have decreased 6 percent since May 1. All regions except the south have seen drying.
