March temperatures a departure from 2012, but not historically low

AMES, Iowa – Cold and snowy weather last month contrasted starkly with the record-high temperatures of March 2012, but a climate expert at Iowa State University said this week that recent temperatures aren’t all that remarkable when accounting for historic patterns.

Iowans across the state have grumbled this year about March temperatures that stubbornly refused to feel much like spring. The average temperature in Des Moines for the month was right around freezing, according to the National Weather Service. That was about six degrees below the historic average but ultimately not a great departure from normal, said Elwynn Taylor, an ISU professor of agronomy.

But with memories of the remarkably warm temperatures of March 2012 still fresh in many minds, comparisons with last year are inevitable. In 2012, temperatures in Des Moines hit 70 degrees on March 6 and, with the exception of one day, never dropped below 50 degrees for the rest of the month. The average temperature in Des Moines was about 16 degrees warmer than average during March 2012.

“Last year we had an extraordinary March because of the high temperatures,” Taylor said. “This year is cooler than normal, but it wouldn’t be considered extraordinary.”

A range of plant life in Iowa, including fruit trees and flowers, awaken from winter dormancy around 50 degrees, and many plants got an early start last year only to hit a roadblock when temperatures dropped below freezing in April.

“We saw record temperatures throughout March in 2012, but things went back to normal the next month,” Taylor said. “We experienced a freeze, which is fairly common for April.”

In fact, Iowans shouldn’t be surprised if temperatures dip below the freezing point this month even after spring-like conditions have taken hold, Taylor said. Iowa may even see more snow this spring, he said.

“We almost always have a snow event, at least from Des Moines and north, in April,” he said. “It doesn’t last long and melts quite quickly, but we usually have some snow.”

He said he doubts that the slow start to spring this year will hamper farmers as they prepare to plant crops, just as last year’s warmth didn’t push many farmers to plant early.

“For most farmers, weather isn’t going to trick them into making mistakes,” he said. “They weren’t fooled last year with the warm temperatures, and this year hasn’t been cold enough to really influence planting decisions.”