As wind chill levels crawl up from 20-below zero overnight, December’s intense cold isn’t a big surprise for Iowa State University Extension climatologist Elwynn Taylor. He says since early August, Iowa’s weather has been affected by one of the most intense La Nina weather patterns on record.
“We really saw this coming, that we would have colder-than-usual weather as the rule over this winter,” Taylor says. He says there will still be warm spells than during a normal winter as part of a “warm-cold battleground” and “you don’t know who’s going to win.”
The La Nina phenomenon is disconcerting because, so far, he says it’s tracking almost identically with a 1973 weather pattern that led to a foul ’74. “If we stay on that track, we’ll become a little bit concerned as we go into spring and next summer because 1974 was a disaster as far as agriculture is concerned,” Taylor says.
The year featured a late spring frost, a very dry summer which ended up being one of the worst droughts since the Dust Bowl days, and an early freeze in the fall.
Taylor says if La Nina conditions continue, Iowa can expect alternating intense cold, punctuated by warm days, throughout the winter ahead.