U.S. weather officials are warning farmers to watch the Pacific closely as the global climate pattern begins shifting from La Niña toward El Niño. The National Weather Service's Climate Prediction Center (CPC) confirmed La Niña persisted through February, but warming subsurface ocean temperatures and weakening trade winds now signal a likely transition during the coming months.

The agency placed the United States under an official El Niño watch, forecasting a 62% probability the event will develop between June and August and persist through the end of 2026.

Still, uncertainty remains over how powerful the event could become.

CPC estimates there is only about a one-in-three chance that El Niño strengthens into a major event by late 2026, highlighting the unpredictability farmers must navigate as planting season approaches.

El Niño Forecast Outlook

Meteorologist Drew Lerner, president of World Weather, says unusually warm subsurface Pacific waters are a key early signal that El Niño is developing. These warming waters are gradually rising toward the ocean surface through a process known as upwelling, which can alter atmospheric pressure patterns and redirect global weather systems.

According to Lerner, the first impacts on U.S. weather may appear within six to eight weeks, with clearer effects expected by mid-summer.

Key Ocean Signals Driving El Niño Development

However, Lerner stresses the timing remains uncertain because strong easterly trade winds across the equatorial Pacific could still delay the event. Some forecast models suggest El Niño could emerge as early as late spring, but long-range predictions beyond three months remain less reliable.

While some meteorologists have warned about the potential for an unusually strong El Niño, Lerner believes those projections may be overstated. He points out that global forecast models sometimes struggle when predicting climate patterns months in advance.

Historically, some major El Niño events-such as the powerful 1998 episode-were not predicted to become extreme until much later in their development. For the 2026 cycle, Lerner expects a moderate El Niño to be more likely, with stronger impacts potentially developing late in the third quarter or into the final months of the year.

Possible El Niño Strength Scenarios

For farmers across the Midwest and Plains, the transition from La Niña to El Niño could shape field conditions during the 2026 growing season. Lerner says rapid transitions between the two climate patterns often produce drier spring conditions in parts of the Midwest and central Plains.

While this dryness may allow farmers to enter fields earlier for planting, it could also place stress on emerging crops if rainfall remains limited.

Regional Weather Risks for 2026

The Delta and southeastern United States could face the greatest challenges if the pattern develops quickly. Existing soil moisture deficits in parts of the Mississippi Valley and Tennessee Basin may worsen if summer rains fail to arrive.

Given the uncertainty around El Niño's timing and strength, experts advise producers to remain flexible with crop management plans. Monitoring soil moisture, irrigation needs, fertilizer timing and planting schedules will be critical as conditions evolve.

A rapid transition to El Niño could also influence commodity markets and crop marketing strategies, particularly if weather shifts affect yields across major producing regions.