Combined high temperatures during August in Trenton averaged 3.6 degrees below normal, despite well above-average temperatures from Aug. 19 through Aug. 25. While high temperatures in August were below normal, low temperatures averaged 2.2 degrees above normal. Highs averaged 83.1 degrees, and lows averaged 67.2 degrees.
High temperatures were in the 90s on seven dates in August, occurring consecutively from Aug. 19 through Aug. 25. They ranged from 92 degrees on Aug. 19 to 97 degrees on Aug. 25. Peak heat indexes measured at KTTN during that period ranged from 112 degrees on Aug. 19 to 121 degrees on Aug. 23. Other peak heat indexes were 120 degrees on Aug. 24, 119 degrees on Aug. 20, 118 degrees on Aug. 22, and 115 degrees on both Aug. 21 and Aug. 25.
The coolest temperature last month in Trenton was 55 degrees on Aug. 18.
Rainfall in August totaled 7.58 inches at the water plant in western Trenton, where official weather measurements are taken for the National Weather Service. The monthly total was 7.22 inches at the residence of Grundy County Emergency Management Director Glen Briggs on East 5th Street in Trenton. The Barton Farm Campus at the southeast edge of Trenton had 6.59 inches of rain last month.
The 7.58 inches of rain at the water plant was the ninth most August rainfall in Trenton since 1970. The greatest August rainfall during that time was 10.47 inches in 1977. The 7.58 inches last month was slightly over three inches (3.06) above normal. However, yearly moisture in Trenton was 4.88 inches below normal entering September.
The National Weather Service’s Climate Prediction Center, entering last month, said above-normal precipitation was slightly favored in this area in August. That turned out to be accurate. Equal chances were given for August temperatures to average above, below, or near normal. The outlook for September shows above-normal temperatures and below-normal precipitation are favored for this area.
