Rainfall moved through Iowa last week, as heavy rains fell in many areas. There were only about 3.5 days suitable for fieldwork, according to USDA’s weekly crop and weather conditions survey.
An unexpected complex of thunderstorms moved through the state on Sept. 14, producing heavy precipitation. “This put a damper on the annual Cy-Hawk football game at Ames but helped improve growing conditions, according to the U.S. Drought Monitor,” notes Iowa Secretary of Ag Mike Naig. “Although it was wet weather for much of last week, we also experienced a nice stretch of above-average temperatures, which is helping the later-planted corn mature.”
The survey shows 74% of Iowa’s 2019 corn crop has reached dented stage, 15 days behind last year and 10 days behind average. Iowa soybeans are running 11 days behind last year in maturity and eight days behind the five-year average.
The U.S. corn harvest is delayed, says the USDA report. Farmers harvested 4% of the nation’s corn crop last week, which is less than the five-year average of 7% for this time of year. Overall condition of the corn crop is rated at 55% good-to-excellent in the top 18 corn-producing states, equal to a week ago. USDA says 93% of the crop was in dough stage last week, compared with a 98% five-year average. And 68% of the corn has entered dent stage, versus an 87% five-year average. USDA is rating the U.S. corn crop 18% in mature stage, versus a 39% five-year average.
The nation’s soybean crop is rated 54% good-to-excellent compared to 55% a week ago. USDA says 95% of soybeans are setting pods, versus a five-year average of 100%. The amount of the U.S. crop dropping leaves is 15%, versus a five-year average of 38%.
The complete weekly Iowa Crop Progress and Condition Report is available on USDA’s site at nass.usda.gov.
Heavy rains fell across much of Iowa, with just 3.7 days suitable for fieldwork statewide during the week ending Sept.15, according to the USDA’s National Ag Statistics Service. Fieldwork activities included harvesting hay and seed corn, chopping silage, and seeding cover crops.
Topsoil moisture condition in Iowa was rated 1% very short, 13% short, 81% adequate and 5% surplus. Precipitation last week helped increase topsoil moisture in all districts. However, the topsoil moisture rating in east central, south central and southeast Iowa districts remains above 25% short to very short. Subsoil moisture was rated 3% very short, 18% short, 76% adequate and 3% surplus.
Iowa’s corn crop is 94% in or beyond the dough stage, over two weeks behind both last year and the five-year average. And 74% of the crop has reached dented stage, 15 days behind last year and 10 days behind average. Eight percent of corn has reached maturity, 19 days behind last year and 13 days behind average. Corn condition improved slightly from the previous week to 65% good-to-excellent.
Nearly all of Iowa’s 2019 soybean crop has started setting pods at 96% statewide, over two weeks behind average. As of Sept. 15, 40% of the crop has begun coloring, 11 days behind last year and eight days behind average. Five percent of soybeans began dropping leaves, almost two weeks behind last year and 10 days behind average. Soybean condition also improved slightly from the previous week to 63% good-to-excellent.
Third cutting of alfalfa hay reached 84%, four days behind average. Pasture condition is rated 43% good-to-excellent. There were a few reports of high numbers of insects around livestock and concerns for livestock in permanent pastures.
Weekly weather summary
According to IDALS climatologist Justin Glisan, an active weather pattern returned to Iowa during the past week, bringing unseasonably wet conditions across much of the state. Parts of northeast Iowa had rainfall totals from 3 to 6 inches above average, while south-central Iowa experienced up to 1-inch deficits.
Unseasonable warmth was also observed across the entire state with temperatures up to 7 degrees above normal. Statewide average temperature was 70.3 degrees, 5.2 degrees warmer than expected.
The week began with rain showers in parts of Iowa on Sunday (Sept. 8) with cloudy conditions statewide. Temperatures stayed in the 60s across Iowa with low 70s in the south. Stronger thunderstorms popped up across central Iowa during early morning hours of Monday. As the storms moved northeast, locally heavy downpours were reported at multiple stations; three stations in Ames (Story County) observed totals from 1.21 to 1.39 inches.
Monday afternoon saw active conditions as a warm front lifted into central Iowa, creating unstable atmospheric conditions that helped force severe weather. A storm moved from west-central Iowa northeast through the evening.
There were reports of severe straight-line winds across 22 counties, with multiple wind gusts of 60 mph and a 70-mph wind in Colo (Story County). Over 80 stations had rainfall above 1 inch, with multiple stations in northeast Iowa observing over 2 inches. Rain totals ranged from 0.01 to 2.85 inches in Persia (Harrison County), with the statewide average rainfall at 0.62 inches.
Thunderstorms lingered into Tuesday (Sept. 10) as storms moved west to east across Iowa. The storms dissipated just after noon as partly sunny conditions prevailed. Highs reached into the low-to-mid 80s. A line of storms moved into northwest Iowa just after midnight on Wednesday with some embedded severe cells. The line lost strength during the morning and fizzled out in the afternoon.
Clouds and rain kept highs in the mid-70s in the north with mid-to-upper 80s in southern Iowa. Isolated storms redeveloped in eastern Iowa later in the evening with some storms moving over the same region. Rain totals were in the range of 0.50 inch to an inch across northern Iowa with heavier totals in the northeast; Dubuque (Dubuque County) reported 3.70 inches.
Thursday (Sept. 12) was another active weather day as a warm front lifted north across Iowa in early morning with multiple lines of showers and storms. Strong storms began to fire in an unstable atmosphere during the afternoon as a cold front swept west to east across the state. Thunderstorms became severe in northeast Iowa during late afternoon with several reports of straight-line wind damage to trees. There was also a report of a weak tornado in Ossian (Winneshiek County).
Rain totals at 7 a.m. on Friday ranged from 0.01 inch at multiple stations to 4.07 inches at St. Ansgar (Mitchell County). With passage of the cold front, Friday was unseasonably cool with clouds gradually clearing the state. Highs reached into the mid- 70s across the state’s southern half and upper 60s in the north; statewide average high was 72 degrees, 4 degrees cooler than normal.
Saturday began with showers and storms across western Iowa moving east through early afternoon. Some of the storms turned severe with multiple reports of pea- to dime-sized hail across central Iowa. Another wave a storms brought locally heavy rain totals to eastern Iowa with Muscatine (Muscatine County) getting 2.96 inches. These storms continued to exit southeast Iowa into Sunday (Sept. 15) morning.
Weekly rain totals ranged from 0.03 inch in Beaconsfield (Ringgold County) to 8.88 inches at Guttenberg Lock & Dam (Clayton County). Statewide weekly average precipitation was 2.54 inches, three times the normal of 0.81 inch.
The week’s high temperature of 93 degrees was reported on Sept. 12 in Muscatine (Muscatine County), 14 degrees above average. Cresco (Howard County) had the week’s low temperature of 44 degrees on Sept. 15,