Released by the USDA National Agricultural Statistics Service

Iowa Secretary of Agriculture Mike Naig commented on the Iowa Crop Progress and Condition Report released by the USDA National Agricultural Statistics Service. The report is released weekly April through November. Additionally, the Iowa Department of Agriculture and Land Stewardship provides a weather summary each week during this time.

“Last week brought widespread rainfall across much of Iowa, including several rounds of thunderstorms and a derecho that developed in eastern Iowa before continuing across parts of the eastern Corn Belt,” Secretary Naig said. “Pleasant weather over the weekend brought out some great crowds for the Iowa State Fair. While there are some lingering chances for storms this week, fairgoers can expect plenty of sunshine and seasonal temperatures.”

Crop report

There were 3.3 days suitable for fieldwork during the week ending Aug. 16, 2026. This is 1.8 days less than last year, when there were 5.1 days suitable for fieldwork. Topsoil moisture condition rated 4 percent very short, 15 percent short, 64 percent adequate, and 17 percent surplus. Subsoil moisture condition rated 5 percent very short, 21 percent short, 63 percent adequate, and 11 percent surplus. Corn silking reached 99 percent, which is 1 percentage point ahead of last year. Eighty-three percent of Iowa’s corn crop has reached the dough stage, which is 6 percentage points ahead of last year. Twenty-six percent of corn reached the dent stage, which is 1 percentage point ahead of last year. Corn condition rated 78 percent good to excellent. Soybeans blooming reached 96 percent, which is on par with last year. Eighty-two percent of soybeans are setting pods, which is the same as last year. Soybean condition rated 78 percent good to excellent. Ninety-six percent of oats have been harvested, which is 6 percentage points ahead of last year. Pasture condition rated 67 percent good to excellent.

The weekly report is also available on the USDA’s website at https://www.nass.usda.gov/.

Weather summary

A large dome of high pressure over the southern United States set up a “Ring of Fire” pattern over Iowa. This atmospheric configuration channeled several waves of thunderstorms, some severe, through Iowa. Rainfall was widespread and well-above average over swaths of the state, leading to the wettest week of the growing season. Conditions were also unseasonably warm with a statewide average temperature of 76.7 degrees, 4.8 degrees above normal.

Thundershowers pushed out of eastern Iowa on Sunday (9^th) afternoon as skies cleared across western Iowa, where temperatures rose into the upper 70s and low 80s. Winds shifted to a northeasterly direction overnight into Monday (10^th) with morning lows varying from the upper 60s north to mid 70s south and patchy fog. Clouds developed over northern Iowa into the afternoon hours, holding daytime highs in the lower 80s; sunshine and southerly wind pushed temperatures into the upper 80s and low 90s farther south. A stationary front draped west to east over Iowa was a focusing mechanism for stronger storms that formed after midnight and expanded across northern Iowa into Tuesday (11^th) morning. Scattered cells consolidated in eastern Iowa, where a squall line developed as a rear-inflow jet began strengthening the mesoscale convective system (MCS). A wind gust of 75 mph in Independence (Buchanan County) was the beginning of what would later be classified as a derecho; the line pushed several hundred miles through the Ohio Valley and dissipated in Virginia. Along with very heavy rain and severe wind gusts in eastern Iowa, two EF-1 tornadoes spun up near Greeley (Delaware County), causing damage to vegetation and outbuildings. Many gauges in eastern Iowa reported at least 0.50 inch with nearly 50 stations at or above 1.00 inch; North Liberty (Johnson County) and Belle Plaine (Benton County) observed the highest totals of 2.33 and 2.48 inches, respectively. Another line of severe thunderstorms pushed into western Iowa by sunrise on Wednesday (12^th) taking a similar but more southerly path through the state. A secondary complex of strong thunderstorms formed in east-central Iowa and sped out of the state by the early afternoon as the disturbance farther west lost energy. Late day conditions were muggy with high dewpoints and temperatures in the upper 80s and low 90s in western Iowa along with ample instability.

A nearly mirror-image MCS with a broader precipitation shield accelerated into Iowa early on Thursday (13^th). The entire complex spanned much of the state with several severe and tornado-warned storms in western and central Iowa; no tornadoes were observed. The southern extent of the squall line dove into southeastern Iowa, producing strong wind gusts and isolated, torrential downpours. The systems exited the state by around noon with clearing conditions in Des Moines (Polk County) for the opening day of the Iowa State Fair. Rain totals for the preceding 36 hours were heaviest from central to western Iowa and then pockets in eastern Iowa; nearly 50 stations collected 2.00 or more inches with 3.05 inches in Gilbert (Story County) to 4.31 inches in Schleswig (Crawford County) and statewide average of 0.90 inch. Winds shifted easterly through the evening and nighttime hours with an ample atmospheric moisture supply for thunderstorms to reform along a surface boundary in west-central Iowa after midnight. Storms expanded west and east, producing multiple flash flood warnings due to heavy rainfall from training storms, as the complex expanded into northern Iowa. The heaviest rainfall dissipated by late Friday (14^th) morning with showers persisting through the day under overcast skies. Daytime temperatures were unseasonably cool, holding in the low to mid 70s across much of Iowa. In addition, 20 stations reported the heaviest totals at 7:00 am on Saturday (15^th) from 3.06 inches in Pella (Marion County), 5.01 inches in Norwalk (Warren County) to 5.31 inches in Wapello (Louisa County). Stations north and south of this swath had general totals of 0.50 to 1.00 inch with a statewide average of 1.03 inches. Showers persisted over southern Iowa before falling apart. Temperatures rose into the upper 70s and low 80s with variable winds and a low-level stratus deck. Scattered showers and a few thunderstorms formed ahead of a cold front transiting the state into the evening hours, with stronger storms in the southeast corner. Twenty-five southeastern stations observed the highest totals, from 1.84 inches in Mount Union (Henry County), 3.05 inches at Burlington (Des Moines County) to 3.49 inches in Fort Madison (Lee County). Sunday (16^th) dawned with foggy conditions, light northwesterly winds and morning temperatures in the upper 60s north to low 70s south.

Weekly rain totals ranged from 0.36 inch in New Market (Taylor County) to 9.45 inches in Wapello. The statewide weekly average rainfall was 2.60 inches, nearly triple the normal of 0.88 inch. Lamoni (Decatur County) reported the week’s high temperature of 95 degrees on the 11^th, nine degrees above normal. Greenfield (Adair County) reported the week’s low temperature of 48 degrees on the 12^th, 15 degrees below normal.