Cool and wet conditions are delaying alfalfa progress in the northern tier of states, a prolonged drought is strangling hay production in the Southern Plains and major floods are setting back the start of harvest along the Mississippi River. Growers might be inclined to think this spring's weather represents something way out of the ordinary.

Not so, says Elwynn Taylor, climatologist with Iowa State University Extension. "What we've been seeing in all of these things is fairly typical coming out of a La Niña winter. We get cold and wet conditions along the Canadian-U.S. border and things typically on the dry side from western Iowa, through the High Plains, all the way to Mexico City."

Taylor notes that the current La Niña, characterized by lower-than-normal surface-water temperatures in the Pacific Ocean at the equator, is the second strongest in the past 100 years. Up to this point, it is almost a carbon copy of the La Niña that developed in the fall of 1973 and remained through the summer of 1974. "That La Niña weakened a bit in May, just as this one has, but it didn't weaken enough to end."

He adds that officials at the National Oceanic and Atmospheric Administration are currently forecasting that there's a 50% chance this La Niña will persist throughout summer. If that's the case, Taylor says, the Southern Plains can expect dry conditions into July. "After that, they'll likely see a return to a normal wet season with things turning back to dry in November."

In the Corn Belt, a persisting La Niña ups the chances of a drought this summer, but only slightly. "It wouldn't be likely, but it does increase the risk some," says Taylor, adding that the Midwest hasn't had a widespread drought since 1988. Even if the La Niña ends within the next six weeks, row-crop yields in the Midwest will likely be "on the shy side of trend."

For hay growers in states bordering Canada, Taylor expects this year's growing-season weather to be similar to last year's. "They could have a dickens of a time getting that first cutting put up," he says. "By the time third crop rolls around, I wouldn't be surprised, under La Niña conditions, to see yields on the short side due to heat and a lack of water."

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