DES MOINES -- Drought conditions across eastern Iowa continue to worsen, according the latest Water Summary Update. The National Drought Mitigation Center’s Sept. 21 U.S. Drought Monitor (USDM) released this morning shows areas of Exceptional Drought (D4) for the first time since the fall of 2012.
While Tuesday saw significant rainfall across portions of the state, most of it fell after the deadline for this week’s Drought Monitor report, so its impact will not be reflected until the Sept. 28 report. Tuesday’s rain – especially in central Iowa, with totals of 2.75 inches in Ames and 3.04 inches in Bondurant – combined with the widespread rainfall forecast for the weekend should help to improve conditions and halt continued degradation.
“After many months of deteriorating conditions, we are hopeful that wetter conditions in the near future will be reflected in the next Water Summary Update scheduled to be published on Oct. 5,” said Tim Hall, the DNR’s Hydrology Resources Coordinator.
Two small areas of Exceptional Drought in Minnesota and Wisconsin have expanded and linked up across northeast Iowa, with another smaller area of Exceptional Drought introduced in east-central Iowa. These areas cover 4.9 percent of the state, and are the greatest extent of Exceptional Drought coverage in Iowa since the start of the U.S. Drought Monitor in 2000, and much greater than the 2.5 percent coverage at the height of the 2012 drought.
Precipitation deficits in the driest parts of Iowa are significant, with Linn and Benton Counties receiving less than 50 percent of normal rainfall over the summer months of June, July and August. This was the record driest summer in those counties. So far, 2023 has been a top 10 driest year for northeast and east central Iowa. Streamflows continue to remain very low across those areas of the state.
“The current drought, which is approaching 170 consecutive weeks of at least D1-Moderate Drought conditions somewhere in the state, has been the longest in the U.S. Drought Monitor’s nearly 24 year period of record," said Dr. Justin Glisan, the State Drought Coordinator and State Climatologist with the Iowa Department of Agriculture and Land Stewardship. "Recent rainfall and short-term outlooks offer hope for improvement which would be reflected in decreasing precipitation deficits, soil moisture recharge, and rising streamflows. The fall months have the potential to provide significant amounts of moisture to the state as we head into the winter.”
The October Water Summary Update will be available on Oct. 5, 2023 on the DNR’s website at
https://www.iowadnr.gov/Environmental-Protection/Water-Quality/Water-Summary-Update.