US corn at risk from heat wave

Jun 21, 2024

Early season timing protects Midwest for now

By Farms.com

A heat wave gripping the central and eastern US is raising concerns about the upcoming corn harvest. While the major corn-producing Midwest may be spared due to the early stage of crop development, southern states are facing a higher risk of crop stress and yield loss.

The National Weather Service issued heat alerts for parts of the Midwest and Northeast, with temperatures exceeding 90 degrees Fahrenheit and a heat index surpassing 100 F in some areas. This heat wave coincides with the silking stage – the beginning of corn reproduction – in the South, making crops particularly vulnerable.

"June is a bad time for a heat wave for corn across the southern United States," says Brad Rippey, a USDA meteorologist. Hotter temperatures during pollination can lead to shorter ears and fewer kernels, impacting overall yield.

The Midwest, where corn hasn't reached the reproductive stage yet, is expected to fare better. However, weather forecasts predict a hotter-than-usual summer across the US, and a potential shift from El Niño to La Niña could further elevate temperatures in the Midwest.

Studies suggest La Niña is linked to hotter summers in this region, raising concerns for future crop development.

Video: Midwest Weather Shock: Flash Drought Turns Into Heavy Rain Threat This Week (2026 Forecast)

A rapidly changing Midwest weather pattern is unfolding in 2026 as areas that recently slipped into abnormal dryness and flash drought conditions are now facing the threat of heavy rain and repeated storm systems.

After a wet spring erased early drought conditions, regions across Illinois, Iowa, Wisconsin, Minnesota, and northern Missouri have quickly dried out again since mid-to-late May. Soil moisture is dropping fast, and crops like corn and soybeans are beginning to feel the stress of rising temperatures and lack of consistent rainfall. Now, weather models show a major shift.

A developing system moving in from the Northern Plains is expected to bring multiple rounds of showers and thunderstorms, with the potential for locally heavy rainfall across the Midwest. While some areas may miss out, others could finally see much-needed relief from the growing dryness. In this video, we break down:

Current drought conditions across the Midwest

Why a flash drought is developing quickly

Timing and path of incoming storm systems

Which states are most likely to see heavy rain

How long this wet pattern could last

Will this rain end the drought or create new flooding risks? Watch the full forecast to find out.