Hay producers who didn’t much care for last year’s growing-season weather should brace themselves. The U.S. as a whole could be in for more of the same during the growing season ahead, says Iowa State University Extension climatologist Elwynn Taylor.

He notes that the National Weather Service’s most recent forecast (released in late February) for the coming summer’s weather is nearly identical to 2009's. “The odds are high that we’ll have warmer than normal in the West and Rocky Mountain states, a condition that often results in cooler than normal east of the Continental Divide,” he says.

The forecast is based on an assumption that a strong El Niño, which reached full development in mid-December, will remain in place. That would be favorable for Midwestern farmers. “An El Niño summer is not oppressively hot,” he says.

If the El Niño falters or fails and is replaced by a La Niña weather pattern, though, the Midwest could see a repeat of 1983. That year, the growing season was characterized by an extremely wet spring followed by a hot, dry summer. “It was a complete disaster for many farmers,” says Taylor. “Right now I’d only give it a one-in-five chance of happening. But that is a real chance.”

The fact that the Midwest is way overdue for a widespread drought increases the odds. The historical average between droughts in the region is 19 years. The longest span between droughts, as indicated by tree-ring records, was 23 years. The last drought was in 1988.

A more immediate concern for many Midwestern farmers, says Taylor, is that high moisture levels in the soil – the result of fall rain and heavy snowfall this winter – could lead to major flooding in some parts of the region. “There’s no reason to necessarily expect a repeat of 2008. But, at the same time, it wouldn’t take a great deal of intense precipitation to result in substantial flooding in parts of Iowa, the Dakotas, southern Minnesota and Illinois. The ground in a lot of places is all full of water right now.”

Follow Taylor on Twitter.