Scattered rainfall allowed Iowa farmers 5.8 days suitable for fieldwork during the week ending July 28, 2024, according to the USDA, National Agricultural Statistics Service. Field activities included harvesting oats for grain, cutting and baling hay, and applying fungicides.
Topsoil moisture condition across the state rated 1 percent very short, 12 percent short, 80 percent adequate and 7 percent surplus. Ratings in west central Iowa were 6 percent very short, 17 percent short, 70 percent adequate and 7 percent surplus.
Subsoil moisture condition statewide rated 2 percent very short, 11 percent short, 80 percent adequate and 7 percent surplus. Ratings in west central Iowa were 7 percent very short, 14 percent short, 73 percent adequate and 6 percent surplus.
Corn silking hit 85 percent this week, two days behind last year but two days ahead of the five-year average. Thirty-four percent of the corn crop has reached dough stage or beyond, one day ahead of last year and four days ahead of average. Two percent of the corn crop has reached the dent stage. Corn condition was rated 77 percent good to excellent.
Eighty-three percent of soybeans were blooming, four days behind last year but one day ahead of normal. Soybeans setting pods reached 43 percent, two days behind last year. Soybean condition was 76 percent good to excellent.
The state’s second cutting of alfalfa hay reached 87 percent complete, four days behind last year but two days ahead of the five-year average. The state’s third cutting of alfalfa hay reached 16 percent, six days behind last year but two days ahead of the five-year average. Hay condition rated 78 percent good to excellent. Pasture condition rated 71 percent good to excellent. Heat stress in livestock was reported.
Weather summary provided by Justin Glisan, Ph.D., State Climatologist, Iowa Department of Agriculture and Land Stewardship – Isolated to scattered showers and thunderstorms were observed almost every day of the reporting period, though most of Iowa’s stations experienced drier than normal conditions. Weekly temperatures varied from slightly above average across portions of central to northwest Iowa to cooler east; the statewide average temperature was 73.9 degrees, 0.4 degree cooler than normal.
Winds were light and variable through Sunday afternoon, July 21, with partly to mostly cloudy skies and temperatures in the upper 70s and low 80s. Scattered thundershowers formed over the evening hours in eastern Iowa before dissipating by midnight. Rain totals were under a few tenths of an inch, though Waterloo (Black Hawk County) observed 1.02 inches.
Northern and eastern Iowa encountered foggy conditions at daybreak on Monday where morning temperatures were in the low to mid 60s. Later in the day, Canadian wildfire smoke filtered into the state, giving a copper-colored fringe to developing cumulus clouds. Isolated pop-up thunderstorms fired in the afternoon across central and southern Iowa before diminishing with the loss of daytime heating. Rain amounts were at or above 0.50 inch at nearly 30 stations with 1.85 inches in Ames (Story County) to 2.13 inches in Lucas (Lucas County).
Overnight lows into Tuesday, July 23, held in the low to mid 60s with patchy fog visible across much of the state. Winds swung to the southwest as daytime highs varied from the 70s east to mid 80s west. Scattered thunderstorms refired along an existing outflow boundary from central to eastern Iowa through the afternoon hours with a secondary cluster later in the evening over northwest Iowa.
A new area of convection pushed into east central Iowa around sunrise on Wednesday before moving into Illinois by late morning. Rainfall totals were more widespread with a broad swath of 0.50-1.00 inch amounts from northwest to east central Iowa; two stations, Swisher (Johnson County) and Central City (Linn County) registered 2.10 and 2.60 inches, respectively. Cloud cover remained over northern Iowa through the afternoon behind a southerly moving cold front, holding highs in the mid to upper 70s while clear skies allowed upper 80s and some low 90s farther south. Scattered thunderstorms developed along the boundary later in the day. Lamoni (Decatur County) collected 1.05 inches while Burlington (Des Moines County) reported 1.58 inches; four stations in Lee County reported totals in the 1.07 to 1.48-inch range.
Thursday morning, July 25, started with upper 50s and low 60s northeast to widespread upper 60s southwest under overcast skies. Winds shifted to an easterly direction through the daylight hours as highs rose into the upper 70s and low 80s under partly cloudy conditions. Clouds spread over most of Iowa into Friday with very spotty, slow-moving thunderstorms in southeast Iowa. Rathbun Dam (Appanoose County) measured 1.40 inches with 2.13 inches in Keokuk (Lee County). A southerly shifting wind helped boost temperatures into the 90s across western Iowa while conditions farther east were more than 10 degrees cooler. A few pulse thunderstorms developed in central Iowa towards the evening with five stations in Dallas and Warren counties collecting more than an inch.
Morning lows on Saturday, July 27, remained unseasonably warm, in the upper 60s and low 70s, with foggy conditions from south-central to northern Iowa. Afternoon conditions were mostly sunny statewide with temperatures in the mid to upper 80s. A weak low pressure center over Missouri spun showers into eastern Iowa later in the evening and persisted through Sunday morning; only a handful of stations observed light rainfall totals.
Weekly precipitation totals ranged from no accumulation in western Iowa to 2.76 inches in Robins (Linn County). The statewide weekly average precipitation was 0.59 inch while the normal is 0.97 inches. Little Sioux (Harrison County) reported the week’s high temperature of 94 degrees on July 25, 12 degrees warmer than normal. Sigourney (Keokuk County) reported the week’s low temperature of 52 degrees on July 26, 11 degrees cooler than normal.
