La Nina advisory is posted, Iowa’s winter weather will be impacted

DES MOINES — The National Climate Prediction Center is issuing a La Nina advisory, indicating Iowa’s winter weather -will- be influenced by the cooling surface of the southern Pacific Ocean.

Doug Kluck, the Central Region’s climate service director at the National Weather Service, says this La Nina pattern is predicted to be fairly weak.  “There is the potential for it to edge up into the strong category,” Kluck says. “One of the things that’s different about this year as opposed to last year is that the atmosphere and the ocean, in the equatorial Pacific, are interacting together — as you would think they should — very well in a La Nina year.”

Kluck, who’s based in Kansas City, says forecasters are hoping the La Nina follows its predicted path.  “From a prediction point of view, that’s good because you rely more on that than influencing North America at some point in the future,” he says.

While there are some indications the La Nina may gain strength during the approaching winter, Kluck says it’s still unclear how strong it may get.  “We try to put labels, we try to quantify strength of La Nina and El Nino all the time,” Kluck says. “If we could put 100% of prediction into La Nina, that’s the way it would look, more or less, across the U.S.”

The winter prediction calls for near-normal temperatures and precipitation across the northern plains, with a chance of colder conditions and more snow in February and March.