Just when you thought scorching droughts were becoming the “new normal” in agriculture, a weather-research firm told the farm media at last week’s Farm Progress Show that 2013 will likely be nothing like 2012.

This fall, the U.S. will exit from a 2-year La Niña pattern of hot and dry weather and enter an El Niño pattern — a warming of the equatorial Pacific — that will dominate the upcoming winter here, says Jeff Doran of Planalytics, which shared its 90-day forecast.

September will usher in a moderating trend, with a more normal precipitation and temperature range. October will represent a near complete shift, with average to below-average temperatures and average to above-average rainfall — and tropical-storm influences still in play, Doran says.

November looks to be relatively cold with a regular invasion of arctic air into the U.S. providing snow cover in some areas, he says.

It’s unclear whether farmers will see enough moisture this fall and winter to restore soil moisture to levels needed for new crop growth. And in published reports, New Zealand scientists recently told Reuters they think the El Nino influence will begin to deteriorate in the 1Q of next year.

But Doran brushed aside suggestions that this year was supposed to be the beginning of a long-lived, massive global warm up.

“We understand that weather is cyclical,” Doran says. “There’s no such thing as runaway global warming.”

The last El Nina-related period in the U.S. came in 2009, which saw heavy spring rains that caused massive nitrogen losses in some fields. Heavy rains also slowed down harvest that year.

It might serve you well to take this information into account as you plan harvest and next year’s fertility and drainage needs. University of Illinois researcher Fred Below reminds us that 230-bushel corn takes up an estimated 150 pounds of nitrogen in a 3-week period — or 7 pounds a day — between V12 and R1, and a total of 200 pounds of nitrogen throughout the plant’s life.

 “That’s why you have to manage nitrogen and have it available at that time, or you’re going to give up yield,” Below says.