Weekly Iowa Weather Report, September 30, 2018

Fall like weather came quick to Iowa.  The last week of September brought cooler temperatures, averaging up to four degrees below normal. Iowa’s center third had above average rainfall sandwiched between below average accumulations in northern and southern Iowa.

Monday was warm and dry, with average highs between 70 and 80 degrees. The warmest conditions were found in northern Iowa, where highs were up to eight degrees above normal. A cold front moved rapidly across Iowa on Tuesday, bringing locally heavy rainfall to the state’s central and eastern portions. Toledo (Tama County) reported the week’s highest accumulation of 2.18 inches. Some storms turned severe with 60 mph wind gusts and tree damage reported in Linn County. A brief tornado touchdown occurred in Mechanicsville (Cedar County) causing minor damage.

Wednesday was a pleasant day across Iowa with abundant sunshine and unseasonably cool temperatures. Daytime highs averaged in the mid-60s and overnight lows dipped into the lower 40s. Another cold front moved across Iowa on Thursday bringing light rain showers to the state’s northern half. Guttenberg (Clayton County) reported 0.58 inches of rainfall. Average highs were in the mid-60s, up to eight degrees cooler than normal.

Rain continued into an unseasonably cool Friday with measurable rainfall across much of Iowa. This trend continued into Saturday and Sunday with spotty showers and thunderstorms across portions of Iowa. Accumulations were generally under an inch both days.

Weekend temperatures were unseasonably cool, with highs in the upper 50s to lower 60s. Holstein (Ida County) observed a high of 48 degrees on Saturday, almost 24 degrees below average; this was the week’s coolest reading. The warmest observation was in Burlington (Des Moines County) with a high of 82 degrees on Wednesday, 10 degrees above average. Statewide average rainfall was about 0.08 inches above the normal of 0.72 inches.

Source:  Dr. Justin Glisan, State Climatologist, Iowa Department of Agriculture and Land Stewardship