Recent heat and humidity helped speed crop development although frequent rains allowed Iowa farmers only 4.0 days suitable for fieldwork for the week ending July 24, according to the USDA, National Agricultural Statistics Service. Activities for the week included aerial fungicide application to corn and cutting hay when fields were dry enough.
Topsoil moisture levels statewide rated 1 percent very short, 9 percent short, 81 percent adequate and 9 percent surplus. Levels in west central Iowa rated 3 percent very short, 16 percent short, 75 percent adequate and 6 percent surplus.
Subsoil moisture levels statewide rated 2 percent very short, 10 percent short, 82 percent adequate and 6 percent surplus. Levels in west central Iowa rated 3 percent very short, 16 percent short, 77 percent adequate and 4 percent surplus.
Eighty-seven percent of the corn crop reached the silking stage, eight days ahead of normal, with 11 percent of the corn crop reaching the dough stage. Corn condition rated 82 percent good to excellent. Soybeans blooming reached 83 percent (88 percent in WC Iowa), six days ahead of both last year and the five-year average. Forty-four percent of soybeans were setting pods, six days ahead of average. Soybean condition rated 81 percent good to excellent last week. Oats harvested for grain or seed reached 54 percent, 2 days ahead of last year.
The second cutting of alfalfa hay reached 87 percent (94 percent in WC Iowa), more than two weeks ahead of last year. The third cutting of alfalfa hay reached 13 percent. Hay condition was rated 73 percent good to excellent, while pasture condition rated 62 percent good to excellent. Pastures and hay crops were growing. Livestock experienced some stress due to high levels of heat and humidity.
Iowa preliminary weather summary by Harry Hillaker, state climatologist, Iowa Department of Agriculture and Land Stewardship – It was a hot, humid, and wet week across Iowa. Temperatures were above normal throughout the week with the hottest weather from Wednesday (20th) through Saturday, July 20-23, when heat indices exceeded 110 degrees somewhere in the state each day.
Actual temperatures during the week varied from a Monday morning low of 55 degrees at Algona July 18 to a Wednesday afternoon high of 97 degrees at Sioux City and Thursday highs of 97 at Des Moines, Lamoni, and Sioux City.
Temperatures for the week as a whole averaged 5.2 degrees above normal. Heat indices reached a maximum of 119 degrees at Shenandoah on Thursday.
Thunderstorms brought rain to the south one-half of the state from Sunday night into Monday morning, July 17-18, with very heavy rains in parts of southwest Iowa. Rain fell nearly statewide on Tuesday with locally heavy rain falling across central Iowa. Wednesday brought rain to extreme eastern and far northwestern Iowa. Another round of thunderstorms brought rain to the eastern one-third of the state on Thursday night into Friday morning, July 21-22. Finally, one last event brought rain to about the north one-half of the state on Saturday morning, July 23, with locally heavy rain in far northeast Iowa.
Weekly rain totals varied from only 0.15 inches at Akron on the South Dakota border to 6.19 inches at Bedford and 6.60 inches between Ankeny and Des Moines. The statewide average precipitation was 2.09 inches, or more than double the normal of 0.98 inches. This was the third consecutive week of much above normal rainfall.