Written by Theresa Rose on October 18, 2016

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

The past reporting week began and ended with unseasonably warm weather with the coldest weather thus far this autumn sandwiched in between. Most noteworthy was a nearly statewide freeze on Thursday (13th) morning. A hard freeze effectively ended the growing season over most of the northwest one-half of Iowa with temperatures falling as low as 24 degrees at Mapleton. The far southeast corner of the state, plus areas near the Mississippi River and scattered upland and urban locations in the southern one-third of Iowa, escaped the freeze. A few locations in far northeast Iowa also recorded a freeze the next morning (Friday). Meanwhile daytime high temperatures were mostly in the seventies on Tuesday (11th), Saturday (15th) and Sunday (16th). Donnellson and Keosauqua recorded the week’s highest temperatures with 84 degree readings on Sunday. Temperatures for the week as a whole averaged 1 to 3 degrees above normal over the northwest and 3 to 6 degrees warmer than normal over the southeast with a statewide average of 4.2 degrees above normal. Rain occurred fairly frequently over the past week, however, rain totals were on the light side in most areas. Light to moderate rain fell across the southeast two-thirds of Iowa from Monday (10th) evening into Tuesday (11th) morning with heaviest rains in south central and southwest Iowa where College Springs (Page County) reporting the most rain with 0.77 inches. Light rain was scattered over much of Iowa on Wednesday (12th) with some heavier rain over the extreme southeast where Montrose (Lee County) picked up 0.90 inches. Mostly light rain fell over the southeast two-thirds of the state on Saturday (15th) into Sunday (16th) morning although a band of one-half to one inch of rain fell from Cedar Rapids to Dubuque. Weekly rain totals varied from only a trace at Rock Rapids and Swea City (Kossuth County) to 1.14 inches at the Cedar Rapids Airport. The statewide average precipitation was 0.24 inches while normal for the week is 0.57 inches. Soil temperatures at the four inch depth were averaging in the mid-fifties over the extreme northwest corner of Iowa to the mid-sixties over the southeast as of Sunday (16th).