Drought conditions persist in Iowa

DES MOINES — Much of Iowa is facing moderate to severe drought conditions, but timely and beneficial rains have at least stabilized conditions for stressed crops, farmers and gardeners.

The latest U.S. Drought Monitor issued Thursday shows severe drought for a larger part of the state — 44 percent versus about 40 percent last week — in an area covering much of northern and central Iowa. That number stood at 8 percent at the start of June.

More than 90 percent of the state is abnormally dry with three-fourths of Iowa in at least moderate drought. A small but growing number of counties in southeast Iowa are reporting normal soil moisture conditions.

"Generally speaking, much of northern Iowa either stayed the same or got worse in terms of the drought depiction this week," said Curtis Riganti, a climatologist at the National Drought Mitigation Center who co-authored the latest U.S. Drought Monitor.

Historically, Riganti said, "this is one of the most significant droughts we've seen in Iowa" in the past century, but it has not been as dry as the 2012-13 period.

Iowa will need above-average moisture and below-average temperatures to flip the negative trends that gradually have worsened since the spring planting and summer growing season unfolded.

Justin Glisan, Iowa's state climatologist, said the past few days of rain were not reflected in the drought report issued Thursday.

But the rainfall helped move this June from the driest start in state history to No. 8 on the list, with a statewide average of 1.51 inches — tied with 1956, with six days remaining in the month.

"We received rainfall right when crops needed it the most, especially after the hot and dry start to June, which is (typically) the wettest month for the northern two-thirds of the state,“ Glisan said.

“The forecast into the weekend looks excellent" for measurable rain through the weekend, he said, "but we need forecasts like that through July and August."

However, he said, longer-term precipitation deficits — on the order of 10 inches to 20 inches — go back six months to more than a year in the driest parts of Iowa in the northwest and west-central sections of that state.

"As we move forward, we would need to see at least an inch of moisture to hold conditions and the (drought monitor) map status quo,“ Glisan said. ”If we remain in a wet pattern, we could see improvement ... though July and August are the hottest months of the year and thunderstorms have become more variable.

"Along with maturing crops using more subsoil moisture, conditions could deteriorate during a dry, hot stretch of days," the state climatologist added. "In general, we need consistent and, in some places, above-average precipitation over the next several months to put a dent in the longer-term deficits."

The weekly water summary update issued Thursday by the state Department of Natural Resources indicated Iowa precipitation totals in June remain 2 inches below normal, with nearly the entire state in some form of dryness or drought.

As a result, streamflow is down across the state, and concern remains for shallow groundwater availability, said Tim Hall, DNR’s coordinator of hydrology resources.

But with rain in the offing, conditions should improve by the next water update on July 10, he said.

A weekly crop report released Monday by the U.S. Department of Agriculture indicated 64 percent of the state's topsoil moisture level was rated short to very short. It said 69 percent of subsoil moisture was in that same range, with crops showing signs of stress from the lack of precipitation and high heat.

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