September wrapped up as a very warm, dry month for Iowa, an about-face from the month before. State climatologist Harry Hillaker says during the last week in the month, Iowans endured temperatures much warmer than normal, well into the 90s in many areas. “The month started out rather on the cooler side. The first seven or eight days, temperatures were well below normal,” Hillaker says. “The rest of the month, with a few small exceptions, was very much on the warmer side. The month as a whole ended up being about 4 degrees above normal for temperatures.”

It ended up being the 11th warmest September in Iowa out of 145 years of record-keeping. Coincidentally, the prior month was the 12th coolest August in Iowa on record. The hottest day of September fell on the 23rd when Iowa City reported 95 degrees, while the coldest report was 35 degrees, both on September 7th in Stanley and on September 30th in Cresco. Rainfall during September was widely varied across Iowa.

“A very dry first half of the month, very little rain anywhere in the state the first half of September,” Hillaker says, “but the rainfall became much more common in the second half of the month, though most areas ended up well below normal.”

While the Fairfield and Ottumwa area was among the driest areas in the state, a storm system on September 20th into the 21st dumped almost eight inches of rain on that area. It ended up making Fairfield/Ottumwa the wettest area in Iowa for September, with nearly nine inches of rain during the month. Burlington had the least rain with only five-hundredths of an inch for the month. As for the month ahead, Hillaker says October promises to be a bit wetter than usual and a potential rollercoaster for temperatures. “Expecting temperatures to average warmer than normal for the month of October, although it does look like we’ll have a fairly cool period for the second week in the month,” Hillaker says. “It’s expected to warm up again after that. On rainfall, it’s slightly favoring above-normal precipitation.”

He says substantial rainfall is possible during this first week in the month. The month of September in Atlantic was nearly five-degrees warmer than normal for a High and three-degrees warmer than the average Low. It was deficient in the form of rainfall, however. Weather data compiled here at KJAN (the official National Weather Service records-keeping site for Atlantic) show the Average High for the month was 81, which was 4.6-degrees warmer than the norm of 76.4.  The hottest day was Sept. 22nd, at 92 degrees. The Average Low was 54.1-degrees, which was 2-degrees above the norm of 51.1. The coolest mornings were on the 6th and 7th, when our Low dropped to 40.

Our normal High for the month of October in Atlantic, is 64, while the average Low is 39. Rainfall during the month amounted to 1.65 inches. We normally see 3.81 inches. The most amount of rain (.72″) fell on the 25th. Rainfall in October typically amounts to 2.76″ in Atlantic.

(Radio Iowa/KJAN records)