OTTUMWA — It sounds hard to believe, but last week's rain didn't help most of the state's struggle with drought. In fact, it got worse in some areas.
The U.S. Drought Monitor released its latest report Thursday morning. For the first time since drought's resurgence this summer, part of the state entered extreme drought. It's a comparatively small area, a patch near Fort Dodge that encompasses only 1.76 percent of the state. But it's unwelcome.
Curiously, you don't need to go far from that patch to find an area of Iowa that has no drought rating whatever. A strip from approximately Dubuque to Waterloo is not considered to be drought-stricken at all. And the area has grown since the last report, expanding to just over 5 percent of Iowa.
Mark Svoboda of the National Drought Mitigation Center, said the week's findings aren't as counterintuitive as they seem. Different factors play into the map's creation, ranging from soil moisture levels to rainfall measurements. And it's important to remember drought doesn't arrive or leave in a single event.
“One thing is, when you're dealing with drought, it's kind of a cumulative impact,” Svoboda said. Instead, it's “a slow dwindling of the water supply.”
So, a given rain event might recharge streams or reservoirs while doing little to resolve drought. That's particularly likely if large amounts of rain fall in a short timespan, as it did last week.
That's when Svoboda said he center relies on contacts on the ground to make sense of the data. He cited State Climatologist Harry Hillaker as an important contact for Iowa. The center's experts can look at the data as recorded; Hillaker can tell them how the event unfolded.