Iowa drought eases with fourth-wettest winter

Pervasive drought in Iowa that peaked in November has been significantly abated by one of the wettest winters on record, according to the state climatologist.

About 89% of the state was suffering from some measure of drought in early November, but that has dropped to about 32% this week, according to the U.S. Drought Monitor.

“December, January, February — the meteorological winter — was the fourth-wettest on record, going back 151 years,” State Climatologist Justin Glisan said.

Precipitation for those three months averaged more than 5 1/2 inches across the state, which is more than double what is normally expected.

The state’s drought was the worst in a decade heading into winter. Even with the improving conditions, most of northwest Iowa still has moderate or severe drought, and there is a pocket of extreme and exceptional drought — the worst classification — south of Sioux City.

That area was plagued last year by dry conditions that hampered crop production.

Frozen soil wasn’t able to absorb all of the precipitation, with runoff from rainfall and melting snow swelling the state’s streams and rivers.

“We’re not quite sure at this point how much of this moisture is getting into the soil, “ said Leah Ten Napel, an Iowa State University Extension field agronomist who monitors the northwest corner of the state.

Still, the persistent precipitation is increasing the capacity for topsoil to retain that moisture in the coming weeks, Glisan said. Surface water acts as a thermal barrier when the temperatures plunge, and the freezing-and-thawing action of the water that has penetrated the soil opens more space for further absorption.

“Overall, it’s been a vast improvement,” he said.

Weather outlooks for this year predict average or above-average precipitation. Drought conditions are expected to continue to improve for the rest of this month in Iowa except for the far western edge of the state, according to the U.S. Drought Monitor.

The National Weather Service reported heavy, wet snowfall on Thursday over a large portion of the state, stretching from its western to eastern borders.

“This is all going to soak in,” said Aaron Saeugling, an Extension field agronomist in southwest Iowa. “The snow — it’s kind of a slow melt — so that will definitely be beneficial.”

He said there’s enough topsoil moisture to buoy newly planted corn and that farmers in his area are likely to start in early April whenever field conditions allow.

“We’re in better shape than what I would have told you two months ago,” he said.