The reporting week began with seasonal temperatures and dry weather on Monday (6th). Tuesday was also dry and was the coolest day with daytime highs mostly in the seventies. Wednesday morning started out unseasonably cool but much warmer and more humid air began pushing into western Iowa by afternoon.

Thunderstorms covered much of the northeast one-third of Iowa between Wednesday evening and Thursday morning although only a few locations picked up more than one-half inch of rain. Hot and humid weather prevailed over most of Iowa from Thursday through Sunday. The exception was far northeast Iowa on Thursday and Sunday where daytime highs were only in the seventies. Friday was the hottest day in most areas with all of Iowa seeing temperatures climb into the nineties. Thunderstorms provided some relief from the heat between Friday evening and Saturday morning across parts of northwest, north central, central and south central Iowa. A few of these storms brought large hail and high winds to portions of northwest Iowa, particularly in Dickinson County.

Locally heavy rain also fell with these early weekend storms, especially from the Charles City area to Cedar Falls and then southwestward toward Marshalltown and Indianola. Waverly reported the most rain for the week with 4.61 inches while much of west central, southwest and far southeast Iowa was dry. The statewide average rainfall was 0.53 inches while normal for the week is 1.19 inches.

Temperature extremes ranged from Wednesday morning lows of 43 degrees at Belle Plaine, Elkader and Grinnell to Friday afternoon highs of 99 degrees at Estherville and Little Sioux. Temperatures for the week as a whole averaged from 2 to 4 degrees above normal across far eastern Iowa to 8 to 10 degrees above normal over the far west. The statewide average temperature was 5.5 degrees above normal.

By Harry Hillaker, State Climatologist, Iowa Department of Agriculture & Land Stewardship