Brace yourself for some extreme weather in 2012.

The La Niña weather pattern that led to rampant flooding in the Northern Plains, devastating tornados in the South and Midsouth and a crippling drought throughout the southern U.S. last year is still in place. Whether the coming growing season turns out to be a repeat of last year’s largely depends on how long this La Niña hangs around.

It’s been one of the strongest on record, notes Brian Fuchs, climatologist with the U.S. Drought Monitor at the University of Nebraska. La Niñas, characterized by lower-than-normal surface-water temperatures in the central Pacific Ocean, typically begin to diminish in April, but this one stayed forceful well into June. The drought it spawned covered an extremely large portion of the southern U.S., ranging from Arizona, along the Gulf Coast and up into parts of the Carolinas.

“In the 10-plus years of the Drought Monitor, we’ve seen pockets around the country that were drier, but we’ve never seen anything so widespread and intense,” says Fuchs.

If water temperatures in the Pacific Ocean warm up from mid- to late February, this version of La Niña may start to subside.“Last year, we didn’t see much movement in those temperatures until later in the winter. By the time the Pacific waters did start to warm, the drought had already started to develop,” he points out.

A diminishing La Niña would likely bring rain to drought-stricken Texas in April and May, historically when the state gets most of its rainfall. Yet if the La Niña stays strong until early April, a major drought continuing into the summer is probable.

“By late March, we should have a much better handle on what the trend is likely to be,” says Fuchs.

Even with significant mid- to late-spring rains, it could take time for rangelands, pastures and hayfields in Texas and neighboring states to return to anything resembling normal, warns Fuchs.

“We saw that in South Dakota a couple of years ago when the state was coming out of an extended drought. A lot has to do with how those lands are managed during the drought. If producers pushed hard to get all of the production they could, it will take longer to recover.”

One indication of just how severely the 2011 drought impacted state grazing lands and hayfields: an early January report from the Texas office of the National Agricultural Statistics Service (NASS). While parts of the state received fairly heavy rainfalls in December, 80% of the pasture and grazing lands were in poor or very poor condition as of Jan. 1.

“There’s still a long way to go for a complete recovery,” says Brad Rippey, USDA ag meteorologist. “And the fact that we’re into a second-consecutive winter with a La Niña in place doesn’t bode well for areas still trying to recover from the drought.”

Producers in the western U.S. could also be dealing with repercussions of a drier-than-normal winter once the new growing season gets under way, Rippey says. As of early January, NASS officials in California were reporting that a lack of rain was deteriorating rangeland conditions and that supplemental feeding of livestock was continuing.

“It was a bit alarming to see that happening in late December and early January. Usually, that kind of brownout is more typical of late spring and early summer. In a typical winter, the pastures and rangelands in California’s valleys are fairly lush and green.”

Significant March and April precipitation could turn the situation around quickly, Rippey adds. “These things are tough to predict more than two weeks out. We can’t assure anyone that the dryness will continue over the next several months. If it does, though, California forage growers and livestock producers will be in trouble come spring.”

Farther north, major hay-growing regions of southern Idaho, eastern Washington and western Montana also experienced dry conditions in late fall and early winter. Yet that’s not unusual, says the Drought Monitor’s Fuchs.

“They had the same kind of situation last year where things were fairly dry through April. But then they had a very wet and cool spring. To this point, the people we work with in the (Pacific Nothwestern) region don’t seem to think there are any real problems developing for the coming growing season.”

La Niña’s continued presence has led to a wet winter in the Ohio River Valley, points out Elwynn Taylor, climatologist with Iowa State University Extension. He expects producers in Ohio, Kentucky and neighboring states will deal with the same kind of extremely wet conditions around planting time this year that characterized 2011 plantings. “But it may not be as extreme as it was last year.”

At least one leading analyst has been forecasting that there’s a 60% chance that an El Niño weather system (warmer-than-normal sea surface temperatures) will be in place by June, Taylor adds. That would be good news for the Corn Belt.

“An El Niño typically translates into above-trend-line yields for row crops and forages in that part of the country,” he says. “As an example, if La Niña continues, corn yields in the Corn-Belt states would average around 148 bu/acre. If we have a switch to an El Niño, the yield average would be closer to 168 bu/acre.”

Also worth noting, Taylor says, is that transitions between El Niño and La Niña events have become more rapid in recent years.

“Historically, the world has spent most of the time in neutral with neither an El Niño or a La Niña present. In recent history, we’re seeing them come one after the other without much of a pause in between. When that happens, what you don’t expect is a normal year.”

Visit bit.ly/A0zopu to hear more of Taylor’s weather predictions.