Iowa farmers had 5.7 days suitable for fieldwork during the week ending August 8, 2021, according to the USDA,
National Agricultural Statistics Service. Field activities continue to include applying fungicides and insecticides and harvesting hay and oats. Some areas of the State have had haying and grazing of CRP lands approved in response to drought conditions.
Topsoil moisture levels rated 18% very short, 35% short, 46% adequate and 1% surplus. Subsoil moisture levels rated 22% very short, 42% short, 36% adequate and 0% surplus. Topsoil moisture levels improved slightly in northwest Iowa while central Iowa topsoil moisture levels deteriorated. Central Iowa topsoil moisture rated 83% short to very short.
Northwest and Central Iowa subsoil moisture both rated 84% or more short to very short. Corn silking or beyond reached 96%, equal to the 5-year average. Corn in or beyond the dough stage reached 64%, four days ahead of average. Eleven percent of the corn crop has reached the dent stage, three days ahead of the 5-year average.
Iowa’s corn condition was rated 61% good to excellent. Ninety-seven percent of soybeans were blooming, 10 days ahead of the 5-year average. Soybeans setting pods reached 84%, eight days ahead of normal. Soybean condition was rated 60% good to excellent. Oats harvested for grain reached 86%, one day behind the 5-year average.
The second cutting of alfalfa hay reached 97% complete. The third cutting was reported at 36% complete, equal to the 5-year average. Hay condition rated 55% good to excellent. Pasture condition was rated 35% good to excellent.
IOWA PRELIMINARY WEATHER SUMMARY
Provided by Justin Glisan, Ph.D., State Climatologist
Iowa Department of Agriculture and Land Stewardship
The first week of August started off with cooler than normal temperatures as negative departures of up to four degrees were observed in southern Iowa. The statewide average temperature was 71.0 degrees, 1.1 degrees below normal. Widespread rainfall was also observed across the state with the highest totals over western Iowa. However, a majority of Iowa’s stations observed precipitation deficits between 0.50 inch and 0.75 inch as extreme drought expanded in northwest and east-central Iowa.
Wildfire haze persisted through Sunday (1st) afternoon with partly cloudy skies and a northerly wind holding temperatures in the upper 70s and low 80s. Clouds increased over central Iowa into Monday (2nd) morning, keeping lows in the upper 50s while the remainder of the state experienced low to mid 50s under clear skies. Variable winds and partly sunny skies produced a pleasant day statewide with temperatures in the 70s. Starry skies and light winds allowed for temperatures to drop into the low 50s across the state’s northern two-thirds with upper 40s reported at a few stations; the statewide average low at 7:00 am on Tuesday (3rd) was 54 degrees, nine degrees below normal. With a high pressure system parked over Iowa, upper 70s were reported during the afternoon hours with winds shifting to a southerly direction as a few clouds passed. Overnight lows into Wednesday (4th) weren’t as chilly as the previous morning with a majority of stations reporting mid to upper 50s, still a few degrees below normal. As the high pressure system pushed east, return flow brought moisture into the region ahead of a low pressure system over Nebraska. Southerly winds helped boost temperatures into the low 80s as muggy conditions returned with higher relative humidity.
Clouds increased from west to east as the low center moved into western Iowa after midnight on Thursday (5th), bringing a line of showers across the state during the early afternoon. Clouds lingered in eastern Iowa with afternoon highs ranging from the mid 80s west to low and mid 70s east. An outflow boundary from thunderstorms in western Minnesota fired strong thunderstorms with locally heavy downpours in northwest Iowa; the line broadened and pushed southeast across western Iowa through Friday (6th) morning. Additional showers and thunderstorms formed in southeastern Iowa. Rain totals for the previous 48 hours were highest in the northwest with a wide swath of totals above 0.50 inch and isolated pockets over an inch; Orange City (Sioux County) measured 1.00 inch while Holstein (Ida County) reported 1.64 inches. Another disturbance skirting the Iowa-Minnesota border brought additional rainfall across northern Iowa and eastern Iowa through Saturday (7th) morning. Totals ranged from 0.01 inch at Cedar Rapids (Linn County) to 0.91 inch at Sibley (Osceola County). Muggy conditions blanketed the state through the day with highs topping out in the low 80s. Another disturbance fired stronger thunderstorms in southwestern Iowa during the late-night hours and into Sunday (8th) with another cluster of storms in east-central and northeast Iowa before sunrise; heavy rain was observed at several stations with a narrow southwest-to-northeast band above 0.50 inch; four stations measured over two inches with Coon Rapids (Carroll County) reporting 2.10 inches while Grundy Center (Grundy County) observed 3.27 inches.
Weekly precipitation totals ranged from no accumulation at multiple stations in southeastern Iowa to 3.37 inches in Grundy Center. The statewide weekly average precipitation was 0.66 inch while the normal is 0.91 inch. Several Iowa stations observed the week’s high temperature of 89 degrees on the 6th and 7th, on average five degrees above normal. Battle Creek (Ida County), Belle Plaine (Benton County), and Elkader (Clayton County) reported the week’s low temperature of 48 degrees on the 2 nd and 3rd, on average 14 degrees below normal.