Soil Temperatures Continue to Decline in November

[December 04, 2018]    Soil temperatures have fallen significantly throughout the state in November, according to Jennie Atkins, Water and Atmospheric Resources Monitoring (WARM) Program manager at the Illinois State Water Survey, University of Illinois.

Soil temperatures measured at depths of 4 inches under sod fell 15 degrees the first two weeks of the month with a state average of 39 degrees on Nov. 14. Temperatures are 8 degrees lower than normal for this time of year and 7 degrees below the average in November 2017.

Soils under sod remain above freezing, but there were cooler temperatures under bare soil. Temperatures averaged 34 degrees at 4 inches under bare soil on Nov. 14, 5 degrees lower than average in November 2017. Lows fell to below freezing at several locations.

Soil moisture declined slightly in November, but remains high. Statewide levels at 2-inch depths averaged 0.37 water fraction by volume (wfv) on Nov. 14, a decline of 8 percent from Nov 1. Soil moisture was near or at field capacity for most of the soils monitored.

Conditions remain slightly wetter at depths of 39 inches and greater.

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 website - http://www.isws. illinois.edu/warm/ and in the Illinois Water and Climate Summary -  http:// www.isws.illinois.edu/warm/climate.asp.

[Lisa Sheppard]