Above normal temperatures were accompanied by widely varying rainfall and some severe weather during the week ending July 23, according to the USDA, National Agricultural Statistics Service. Statewide there were 5.4 days suitable for fieldwork. Activities for the week included hauling grain, applying herbicides and insecticides, cultivating, and haying.
Topsoil moisture levels statewide rated 20 percent very short, 32 percent short, 45 percent adequate and 3 percent surplus. West central Iowa was drier than the state average with ratings at 25 very short, 42 percent short, and 33 percent adequate.
More than 90 percent of south central Iowa’s topsoil falls into the short to very short moisture level categories, while 99 percent of northeast Iowa’s topsoil falls into the adequate to surplus categories.
Subsoil moisture levels statewide rated 14 percent very short, 32 percent short, 52 percent adequate and 2 percent surplus. Ratings in west central Iowa were 12 percent very short, 44 percent short, and 44 percent adequate.
Seventy-four percent of Iowa’s corn crop has reached the silking stage (80 percent in west central Iowa), four days behind last year but two days ahead of the 5-year average. Corn conditions deteriorated slightly to 2 percent very poor, 6 percent poor, 24 percent fair, 55 percent good, and 13 percent excellent.
Nearly three-quarters of the soybean crop was blooming, with 30 percent of soybeans setting pods, one day ahead of average. Soybean condition also dropped slightly with 62 percent rated good to excellent. Crops were described as suffering from heat stress and lack of moisture across much of the state.
The second cutting of alfalfa hay reached 90 percent complete and third cutting reached 8 percent, five days behind average. Hay condition rated 61 percent good to excellent. Pasture condition continued to decline with just 41 percent good to excellent. High temperatures and humidity were reported to cause normal summer heat stress to livestock, with some reports of heat-related deaths.
Iowa preliminary weather summary by Harry Hillaker, state climatologist, Iowa Department of Agriculture & Land Stewardship – It was a hot and humid week across Iowa with exceptionally variable rainfall. Major flooding occurred over parts of northeast Iowa where torrential rains fell Friday and Friday night, July 21, while parts of the moderate drought area in south central Iowa received no rain at all.
For the most part the heavier rains fell in what were already the wetter portions of the state. However, portions of the moderate drought area, roughly along U.S. Highway 30 from Crawford to Tama counties, saw some significant rain on Thursday night.
Weekly rain totals varied from none at Murray, Osceola, Chariton and Allerton to 10.12 inches at Ionia in Chickasaw County. Rain totals thus far in July vary from only 0.16 inches at Sioux Rapids and Cherokee to 13.88 inches at Guttenberg. The Guttenberg July total is the highest for any month at that location among 86 years of record, while the Cherokee and Sioux Rapids totals would be new record lows for July if no more rain were to fall before the end of the month.
Some of the rain was accompanied by severe weather with the most damaging storms occurring across 15 north central and northeast counties, roughly north of an Estherville to Dubuque line, on Tuesday afternoon and evening with widespread high winds of 50 to 70 mph and a few tornadoes.
Meanwhile hot weather prevailed with the temperature reaching 95 degrees somewhere in the state each day of the reporting week. The hottest weather was concentrated across southern Iowa with temperatures for the week averaging from two to three degrees above normal across the northeast one-third of the state and five to nine degrees above normal across the southwest.
Highest temperatures were 101 degree readings at Ottumwa on Thursday and Des Moines on Friday. These were the highest temperatures recorded in Iowa since September 9, 2013. The combination of heat and humidity produced a heat index (how hot the air ‘feels’) of 117 degrees at Clarinda on Thursday and at Harlan on Friday.
Temperatures moderated over the weekend with Sheldon recording a morning low of 52 degrees on Sunday, July 24. The statewide average temperature was 5.3 degrees above normal while rain averaged 1.42 inches compared to a normal of 0.99 inches for the week.