Farmers Might As Well Ditch Their Long-Range Weather Forecasts

Farmers hoping for a calm, predictable second half to the 2026 growing season are unlikely to get it, according to meteorologist Don Day of DayWeather.

Speaking to Pioneer field agronomists on an episode of Kick’N Dirt earlier this week, Day says he expects a surge in weather extremes from July through harvest — and holds unusually low confidence in long-range forecasts.

According to Day, a volatile atmospheric pattern is emerging from a direct clash between a rapidly warming El Niño in the Pacific and an exceptionally cold Arctic. The combination is one that current computer models are struggling to process.

“We are looking at the coldest spring in the Arctic since 1958,” Day says. “With the cold Arctic and this really warm, moist El Niño coming on, the extremes will probably be more common than our [typical] weather.”

Delayed Summer Warming Trend

In much of the Midwest and Corn Belt, growers have experienced an unusually cool start to the season. Pioneer Field Agronomist Kevin Kowalski questioned Day about the industry “hype around a super El Niño” and what it might mean for summer storm levels, insect movement, and crop disease pressure.

Day notes that the current cool pattern will likely linger into early July before summer conditions finally take hold.

“For the next 10 days, the Midwest and Corn Belt are going to have below-average temperatures,” Day says. “That is not El Niño at all. That is a northern latitude influence of the Arctic being a lot colder than it normally is this time of year.”

However, Day says he expects the jet stream to flip as July gets underway.

“Around the Fourth of July, and probably through August, we do see the establishment of a pattern that will start to bring that southerly flow in, so that should start to bring in some warmer temperatures and higher humidity,” he says.

In a more typical summer, that heat and moisture would already be established, Day adds, noting that the entire seasonal pattern appears to be running about four weeks behind schedule.

Disease And Insect Risks Rise With Humidity

Kowalski connected the sluggish warmup to tar spot outbreaks already appearing in parts of the Midwest under cool, wet conditions. He asked Day whether a shifting south-to-north airflow later this summer could pull southern rust and migratory insects deeper into the Midwest.

Tar spot thrives in prolonged cool, wet conditions. Agronomists warn that if a sudden wave of heat and humidity slams into the Corn Belt in July, it could cause the disease to explode right during critical crop pollination windows, making intensive field scouting vital.

Day replies that while the current dominance of Canadian air has temporarily suppressed pest and disease pressure, that window is starting to close. As summer heat and humidity finally arrive, increased pressure will likely follow.

Because weather models have consistently lagged in predicting the onset of this sustained summer pattern, Day urges farmers and advisers to view long-range outlooks with some skepticism.

“Every time we’ve expected the summer pattern to develop, it gets delayed, and that’s how the entire month of June has gone,” Day notes.

Western High Plains States Await Relief

Pioneer agronomists Mike Wardyn and Kowalski also raised concerns about the Nebraska Panhandle, eastern Wyoming, and eastern Colorado — regions that are dealing with ongoing drought.

Wardyn notes that many growers in his region are already facing tight restrictions on irrigation water, making the failure of early-summer monsoon rains a heavy blow to farmers’ corn yield potential.

Day says meaningful relief for the Western High Plains depends entirely on whether the jet stream shifts far enough north to allow subtropical moisture to flow in from Mexico and Central America. Currently, he adds, cool and dry Canadian fronts are blocking the typical early-summer monsoon that feeds seasonal thunderstorms.

“What will take the Panhandle and eastern Colorado and eastern Wyoming to get wet is to get rid of this pattern that’s making it so cool in the Midwest, because that’s closing the door to that subtropical moisture,” Day explains.

While European and Canadian forecast models predict moisture returning to these regions in July and August, Day remains skeptical.

“My confidence in those models is so bad right now that it’s really hard for me to put much stock in them until we see it happen,” Day says, adding that entrenched drought conditions create a feedback loop that makes local recovery difficult.

“When you finally do get thunderstorms to come into your area, you have got to have some type of feed of deeper low-level moisture for that thunderstorm to come through you and make it rain a lot,” he adds. “Weather does not treat people equally, that’s for sure.”

El Niño’s Punch Saved For Fall

Despite the headlines surrounding a “Super El Niño,” Day reminded the Pioneer agronomic team that the phenomenon’s strongest impacts rarely hit North America during summer months.

“The biggest impacts of El Niño tend to come later — fall, winter, spring,” Day says. “For folks who are expecting El Niño to start making an impact in our weather this summer... we’re not seeing El Niño at all having any impact so far.”

Furthermore, Day cautions that the central U.S. — specifically regions north of Interstate 70 and into the I-80 and I-90 corridors — sits right on the historical edge of El Niño’s wet weather signal. In some years, the storm track pushes far enough north to benefit these areas; in others, it misses them entirely.

“No two El Niños are the same in this part of the world,” Day says. “Only in the far southern U.S. is it consistently the same.”

Risk Of Early-Season Cold Shots

Looking toward harvest, Wardyn asked Day what growers should anticipate as crops finish up in September and October, particularly in areas where recent hail and wind damage forced farmers into late-season replanting. Day’s primary concern for this fall is a faster transition to winter weather.

“I do think that there is a higher risk this year of an early-season cold shot,” Day warns, pointing to historical El Niño activity that brought volatile, cold conditions to the Central Plains in late September and October.

For growers who have grown accustomed to long, warm falls — and have pushed corn maturities fuller-season as a result — this pattern presents a distinct vulnerability. Kowalski notes that many Pioneer customers have shifted toward longer-maturity products in recent years, betting on a continuation of recent warm, dry falls.

The concern is If a late-planted crops are hit by an early freeze before reaching full maturity, it can result in low test weights, field losses, and high propane bills for mechanical grain drying.

Day says there are some hints that the weather in October could be more like those from a decade-plus ago – “which are colder, maybe some wintry weather coming in—something to keep an eye on.”

An ‘Angry Stratosphere’ Limits Model Accuracy

Beyond El Niño, Day attributes much of the current atmospheric confusion to the lingering aftereffects of the 2022 Hunga Tonga volcanic eruption, which he says injected unprecedented volumes of water vapor into the stratosphere. He believes this event is directly responsible for the Arctic cold and the ongoing poor performance of global forecast models.

“I really think we’re getting a hangover from it,” Day says. “We can draw a direct parallel to what happened this winter with the stratospheric impacts, because the stratospheric impacts tend to be bigger in the higher latitudes, and if the higher latitudes are affected, we’re affected eventually.”

He adds that the resulting meteorological combination is uncharted territory for modern forecasters.

“The stratosphere is angry and the El Niño is strong, but we don’t quite know how those two are going to mix this winter,” he notes.

As a result, Day admits he has “the least amount of confidence in any seasonal forecast that I’ve ever had in doing this for 30-plus years.” He explains that global models are built on historical baselines and cannot easily adapt to unprecedented atmospheric inputs.

“Models are like houses — once they’re built on a foundation, you can’t just go into the computer and tell the model to do something different, you have to rebuild it,” Day explains. “That’s why I think the seasonal forecasting has been so poor, because the models are not ingesting these peculiarities that we’re seeing right now.”

Managing Risk Week-To-Week

When asked how farmers should navigate this summer and fall under such high uncertainty, Day advised narrowing the planning horizon and maintaining operational flexibility.

“One, maybe two weeks at a time is all we can really expect,” Day says. “Proceed with caution on anything you see, whether it’s a six-to-10-day forecast or a 30-day outlook.”

With a freezing Arctic, a surging Pacific El Niño, and a disrupted stratosphere all competing for dominance, Day expects the remainder of 2026 to stay highly volatile.

“I would like to say things are going to even out and be a little more tranquil,” he says, “but I would expect these extremes to continue.”