Eastern Iowa only area with concern in first NWS spring flood outlook
JOHNSTON — The National Weather Service’s first look at the potential for flooding this spring shows most of the state in good shape.
Hydrologist Jeff Zogg says eastern Iowa is the only area raising concern. “The first flood outlook for the state of Iowa for this spring is showing a near to below-normal risk of flooding. And most streams in the state the main exceptions, the Mississippi River in far eastern Iowa, where the risk is above normal,” Zogg says.
The snowpack in eastern Iowa is one part of the equation that raises the risk for the Mississippi River for flooding. “We consider a bunch of different factors when we assess the spring flood risk. We look at river levels, soil moisture, the snowpack, specifically, the liquid content, how much water is in that snowpack, frost depth, and we also consider the temperature and precipitation outlooks,” he says.
Zogg says this year’s outlook is typical of the recent pattern. “For the past couple of years, the spring flood outlooks have been pretty favorable for the state, not really any high risk of spring flooding across the state,” Zogg says. “Some locations, maybe a little bit above normal. Kind of like this year, the Mississippi is above normal risk, not much above normal, but above normal.”
The second flood outlook will be released on February 23rd and Zogg says the updates take into account the forecast ahead. “The big thing that we have to look at is the future precipitation, things like rainfall or snowfall,” he says. “Of course, much of the face on a drought, so we would welcome the rainfall, it’s just that we don’t want it all at once. We want that rainfall spread out over time.”
These flood outlooks are for the long-term potential for river flooding. “They really don’t consider things like flash flooding, it’s more of a shorter-term hazard. That’s usually in response to a localized heavy rainfall event,” Zogg says. “So, people still need to be aware of the potential for that if we have any heavy rainfall events going forward. And as people who live in Iowa for a while now, we can definitely get heavy rainfall events in the spring and summer.”
The third and final spring flood outlook will be released on March 9th.