Farmers are keeping a close eye on the Pacific as La Niña, which has dominated weather patterns across much of 2026, begins to give way to El Niño. The National Weather Service Climate Prediction Center (CPC) now reports La Niña persisted through February, with below-average sea surface temperatures across the east-central equatorial Pacific. However, rising subsurface ocean temperatures and weakening trade winds signal a likely shift to El Niño by this summer, potentially bringing dramatic changes to rainfall, planting conditions and crop development across the U.S.
CPC says that means the US. is now under an El Niño watch, forecasting a 62% chance that El Niño will emerge between June and August and continue through the end of 2026. But the event’s ultimate strength remains uncertain.
“There is only about a one-in-three chance that this could become a strong El Niño during October to December 2026,” CPC notes, underscoring the unpredictability farmers must plan around this year.
This transition from La Niña to El Niño could have major implications for the spring planting season in the Midwest, the central Plains, and the Southeast, where early dryness or shifting rainfall patterns may affect field work, soil moisture and crop progress.
While some meteorologists are saying there are signs this could be an extremely strong El Niño event, Drew Lerner, president of World Weather, cautions that strong of a declaration just yet.
A #LaNina advisory remains in effect. An #ElNino Watch has been issued. (2/2) https://t.co/5zlzaZ0D9Z pic.twitter.com/WpmK4dNKfn
— NWS Climate Prediction Center (@NWSCPC) March 12, 2026
Subsurface Ocean Warming Signals Early El Niño Development and Global Weather Shifts
What we do now is La Niña is making a quick exit.
Lerner says the current ocean subsurface warming is the early trigger for El Niño, which has far-reaching effects on weather patterns worldwide.
“The ocean subsurface water temperatures are anomalously warm, and we do see a strong upwelling current taking place as we move forward through the next several weeks,” Lerner says. “That will bring that warmer-than-normal water from below the surface up to the top. Once you bring it to the surface, you start shifting high and low pressure systems around the world. That’s when you’ll see El Niño beginning to influence everybody’s weather.”
Lerner notes farmers may not see immediate effects, but the pattern will begin influencing U.S. weather in a few weeks and become more pronounced by mid-summer.
“This is probably six to eight weeks before we really start to see any influence, and it will become more significant as we go through the Northern Hemisphere summer months,” he says. “We’ll likely see this El Niño become a little better defined by July and August.”
Understanding this early subsurface warming is critical for farmers to anticipate planting conditions, irrigation needs and crop development challenges.
Timing of El Niño Formation Remains Uncertain Despite Increasing Odds
While CPC forecasts a 62% chance of El Niño forming by late summer, Lerner warns several factors could shift or delay the event, making early-season planning more complex.
“There are a number of factors that could change that forecast quite a bit,” he says. “The Climate Prediction Center modified its official forecast from the raw model data. If you go to their website, you’ll see the actual forecast from their models suggests El Niño could be here in May, maybe even late April. The Australian Bureau of Meteorology also suggests it could begin in May or June. If that happens, weather around the world could start to change fairly quickly.”
Lerner stresses long-range forecast models are more reliable over three months and cautions farmers against assuming early signals guarantee timing or intensity.
“One factor is the strong easterly winds blowing across the equatorial Pacific,” he says. “If those winds lighten, it could delay the onset of El Niño. I have a lot of confidence we will move into an El Niño during the summer months, but the intensity and exact timing are still uncertain. My biggest question is how intense it will be, and at the moment, I want to play that down compared to what some forecast models have been suggesting.”
Farmers should track the weakening of trade winds and ocean temperature patterns closely, as these will influence planting schedules and fieldwork conditions in the coming months.
How Strong Could This El Niño Be?
Farmers are concerned about the potential strength of this El Niño, given its impact on rainfall, drought risk and crop yields.
“In 1998, we had a really strong El Niño that was disastrous, but it wasn’t predicted to be nearly as strong early on as it ended up being,” Lerner says. “This year is unprecedented in terms of early signals. It may also test our improved models, which attempt to forecast more than three months out. I think these models may be overreaching a little, and we could see the El Niño develop more slowly than some models suggest.”
Lerner predicts a moderately strong El Niño is possible, with peak impacts more likely in the latter part of the third quarter or into the fourth quarter of 2026.
“We might get to a very strong event, but not nearly as quickly as what some of the model data suggests today,” he says. “A moderately strong El Niño is a possibility, more likely later in the year.”
Farmers should be cautious about making early assumptions regarding extreme drought or flood events and plan for gradual changes in conditions.
Potential Impacts on U.S. Growing Season: Drier Springs, Variable Summer Rainfall
For U.S. farmers, the timing and intensity of this El Niño could bring mixed outcomes for planting and crop development. Lerner says a rapid transition from La Niña to El Niño can produce a drier bias in key agricultural regions.
“Our studies show that when we move quickly from a La Niña in January to an El Niño by June, the Midwest tends to have a drier bias in the spring,” he says. “This is particularly true in hard red winter wheat country and the central and southeastern Plains. That’s a concern because we already have dryness in some areas. A quickly developing El Niño could mean a fairly dry spring. That will help with field progress moving quickly, but crops may be limping along for a while.”
While spring dryness could help farmers get into the fields earlier, it may also stress emerging crops if rainfall does not arrive in time.
Lerner adds summer rainfall will likely vary by region.
“In the summer, situations like this often show improvement in rainfall in the Midwest and Northern Plains,” he says. “But the Delta, Mid-South, and southeastern U.S. have a tendency toward a drier bias with quickly developing El Niños. We already have some moisture deficits in the Delta, Tennessee basin and southeastern states. If rain intensities remain low, dryness could worsen as we move into late summer.”
Farmers in these regions may need to plan irrigation strategies and monitor soil moisture closely to offset potential dry spells.
Planning Ahead for Crop Management: Field Decisions, Irrigation and Risk Strategy
Lerner advises farmers to monitor early signals from the Pacific closely and to prepare for variability in precipitation and temperatures throughout the season.
“A quick movement from La Niña to El Niño could cause some spring problems in the Midwest, but much better conditions in the summer,” he says. “Meanwhile, the Delta and Southeast would probably see progressively more significant dryness by late summer. Farmers need to be aware and prepare accordingly.”
The key, he says, is understanding both the speed of El Niño development and its intensity to make informed decisions for planting, irrigation and crop management strategies.
“Pay attention and prepare for a spring with potential dryness in some areas and moderate rainfall improvement in others as the season progresses,” Lerner says. “This could influence how you handle fieldwork, fertilizer application and even crop marketing as the season develops.”