Continued dry weather allowed Iowa farmers 6.7 days suitable for fieldwork during the week ending Aug. 30, according to the USDA, National Agricultural Statistics Service. Drought conditions and rapidly drying crops are now a concern for most of the state. Field activities included harvesting hay, chopping corn silage and harvesting seed corn. Some farmers have been cleared to mow or disc in their corn damaged by the derecho.
Topsoil moisture condition statewide rated 41 percent very short, 40 percent short, and 19 percent adequate. The state’s topsoil moisture condition deteriorated to 81 percent short to very short. In west central Iowa, ratings were 62 percent very short, 32 percent short and 6 percent adequate.
Subsoil moisture condition across Iowa rated 37 percent very short, 40 percent short, and 23 percent adequate. The state’s subsoil moisture condition dropped to more than three-quarters short to very short. Ratings in west central Iowa ere 58 percent very short, 33 percent short and 9 percent adequate.
Corn was 95 percent in the dough stage or beyond, more than two weeks ahead of the previous year and six days ahead of the 5-year average. Almost three-quarters of the corn crop was in or beyond dent stage, over two weeks ahead of the previous year and one week ahead of average. The crop seems to be speeding towards maturity with 11 percent of the crop mature, 18 days ahead of last year and six days ahead of average. Corn condition rated 45 percent good to excellent, a drop of 5 percentage points from the previous week and the lowest level since the week ending Oct. 20, 2013.
Soybeans setting pods were more than two weeks ahead of last year and four days ahead of average at 96 percent. Soybeans coloring reached 29 percent. That is the highest percentage of soybeans coloring by August 30 since 2012. Soybean condition fell again this week with the crop now rated 50 percent good to excellent, the lowest level so far this season.
Alfalfa hay third cutting was 86 percent complete, almost three weeks ahead of last year and 11 days ahead of the 5-year average. Pasture condition fell 7 percentage points this week to just 16 percent good to excellent. Many cattlemen have had to begin supplemental feeding of hay due to deteriorating pasture conditions.
Iowa preliminary weather summary provided by Justin Glisan, Ph.D., state climatologist Iowa Department of Agriculture and Land Stewardship – The week of Aug. 24-30 was the driest reporting period of the summer and of the 2020 growing season thus far. All Iowa stations, with the exception of one, reported below average precipitation with deficits near an inch at rain gauges in eastern Iowa. Much of the reporting period also had temperatures well above average with the highest departures, on the order of 10-12 degrees, in western Iowa. The statewide average temperature was 77.3 degrees, 6.1 degrees warmer than normal.
Sunday, Aug. 23, afternoon temperatures pushed into the low to mid 90s under mostly sunny skies and variable winds. Morning lows on Monday did not retreat substantially, remaining in the upper 60s and low 70s. Patchy low-lying fog was reported near sunrise at many stations in northeastern Iowa. With a light southerly wind and hazy conditions from western wildfire smoke, daytime highs rose into the mid to upper 90s; the statewide average high was 94 degrees, 13 degrees above normal, making it one of the warmest days of the year.
Overnight lows into Tuesday, Aug. 25, were similar to those observed on the previous day with a small area of very light rain in northwest Iowa. Afternoon temperatures remained well above average, in the 90s under breezy and sunny conditions.
Temperatures reported on Wednesday were unseasonably warm, lending to a muggy morning. Readings ranged from the upper 60s to mid-70s with an average low of 68 degrees, nine degrees above normal; Fort Madison (Lee County) observed 76 degrees, 11 degrees warmer than normal. High temperatures were slightly cooler, generally in the low to mid 90s.
Thursday, Aug. 27, was yet again warm, though clouds started to filter into the state ahead of a low pressure center in Nebraska. The system propagated along the Iowa-Minnesota border over the evening hours through early Friday morning, firing showers and thunderstorms. Some of the thunderstorms were strong, leaving behind measurable rain across the northern first tier of counties. Totals were light ranging from 0.01 inch in Spencer (Clay County) to 0.78 inch in Elma (Howard County). The low pressure center’s attendant cold front moved through Iowa during the day creating a temperature spread from the low 80s northwest to low 90s southeast. Thunderstorms fired along the front though the evening hours in eastern Iowa, some turning severe. There were a handful of reports of one-inch hail and straight-line winds causing isolated structural and tree damage in Hopkinton (Delaware County). Widespread measurable rain also fell across the state with totals of up to 0.75 inch in De Witt (Clinton County) and Osage (Mitchell County). Many stations that did report rain generally observed a few tenths of an inch with a statewide average total of 0.07 inch.
Morning temperatures on Saturday dipped into the low to mid 50s across northern Iowa behind the front, as winds shifted to a northerly direction. Afternoon conditions were pleasant with near seasonal temperatures in the upper 70s and low 80s. Overnight lows into Sunday dropped into the mid-50s with some upper 40s in north-central Iowa. The statewide average low was 51 degrees, seven degrees cooler than normal.
Weekly precipitation totals ranged from no accumulation at more than half of Iowa’s stations to 1.68 inches in Monticello (Jones County). The statewide weekly average precipitation was 0.11 inch while the normal is 0.96 inch. Several stations reported the week’s high temperature of 99 degrees on Aug. 24, on average 18 degrees warmer than normal. Chariton 1 E (Lucas County) reported the week’s low temperature of 44 degrees on Aug. 30, 13 degrees below normal.
