IOWA PRELIMINARY WEATHER SUMMARYWritten by Theresa Rose on September 27, 2016
By Harry Hillaker, State Climatologist, Iowa Department of Agriculture & Land Stewardship
It was yet another very wet week across much of Iowa. Scattered thunderstorms brought rain from south central to northeast Iowa on Monday (19th) and over the extreme northeast corner of the state on Wednesday (21st) morning. Rain was widespread over the northern one-half of Iowa from Wednesday afternoon to Thursday (22nd) morning with torrential downpours in north central into northeast Iowa with record flooding along the Shell Rock River. Thunderstorms were again widespread over the northern two-thirds of the state Thursday afternoon into Friday (23rd) morning with heaviest rains centered upon Buchanan and Delaware counties. Finally, another episode of widespread rain impacted the western two-thirds of Iowa from Saturday (24th) afternoon into Sunday (25th) morning with heaviest rains in southwestern portions of the state. Rain totals for the week were exceptionally variable with no rain falling over the southeast portion of Iowa at such locations as Albia, Ottumwa, Fairfield and Burlington while Nora Springs reported 11.07 inches and Nashua 9.76 inches in Floyd County. The statewide average precipitation was 1.95 inches while normal for the week is 0.77 inches. The statewide average rainfall thus far in September has averaged 6.29 inches, the highest September average since 1986. However, once again, the rain totals this month vary widely from only 0.90 inches at Fairfield to 17.25 inches at Nora Springs. A higher September precipitation total than seen in Nora Springs has occurred in Iowa in only 1926 and 1970. Meanwhile it was a very warm and humid week across the state. Temperatures averaged from nine degrees above normal across the northeast to as much as 14 degrees above normal in the south with a statewide average of 12.1 degrees above normal. Temperature extremes varied from a Tuesday (20th) morning low of 47 degrees at Cresco to Wednesday (21st) afternoon highs of 94 degrees at Atlantic, Algona, Clarion and Indianola.