# Iowa's Record-Breaking Heatwave: Impact on Corn and Soybean Harvest (2026)

> Iowa experienced one of its warmest Septembers on record, with a statewide average weekly temperature of 79.8°F. Corn was 77% good to excellent but only 17% mature, slightly behind schedule. Soybeans were rated 75% good to excellent but lagged last year's pace, with 6% dropping leaves.

- Date: 2026-11-01 · published 2026-11-01T12:10:57.578Z
- Category: weather · region US · magnitude low
- Page: https://feedsoft.ai/events/8925-iowa-s-record-breaking-heatwave-impact-on-corn-and-soybean-harvest-2026
- Commodities: [Corn](https://feedsoft.ai/c/CORN.md), [Soybeans](https://feedsoft.ai/c/SOY.md)

## Why it matters

Heat-delayed maturity pushes harvest timing back and raises weather-related yield risk in a key Corn Belt state. Good crop ratings limit the price impact, so the effect on corn and soybean prices is modest.

## Read by commodity

- SOY: bullish ▲
- CORN: bullish ▲

## Similar past events

| Commodity | Date | Event | 5-day % | 20-day % |
| --- | --- | --- | --- | --- |
| CORN | 2021-07-23 | [How record heat could affect the U.S. corn and soybean markets - DTN](https://feedsoft.ai/events/45915-how-record-heat-could-affect-the-u-s-corn-and-soybean-markets-dtn.md) | -1.1% | -2.6% |
| CORN | 2026-01-29 | [Heat wave hits Argentina, threatening corn and soybean crops](https://feedsoft.ai/events/13817-heat-wave-hits-argentina-threatening-corn-and-soybean-crops.md) | -0.3% | -0.1% |
| CORN | 2026-07-17 | [IGC Reports Heatwaves in Europe Lower 2026/27 Global Cereal Harvest; Soybean and Rice Outlooks Adjusted \| Tridge Insights](https://feedsoft.ai/events/18398-igc-reports-heatwaves-in-europe-lower-2026-27-global-cereal-harvest-soybean-and.md) | +3.6% | -1.5% |
| CORN | 2026-04-06 | [Climate concerns second corn crop and soybean harvest advances to 82% in Brazil](https://feedsoft.ai/events/13439-climate-concerns-second-corn-crop-and-soybean-harvest-advances-to-82-in-brazil.md) | -1.8% | +2.8% |
| CORN | 2020-12-11 | [Farsul projects 2020/2021 harvest with new drop in corn and recovery in soybeans - Revista Cultivar](https://feedsoft.ai/events/49479-farsul-projects-2020-2021-harvest-with-new-drop-in-corn-and-recovery-in.md) | +1.9% | +11.2% |
| SOY | 2021-07-23 | [How record heat could affect the U.S. corn and soybean markets - DTN](https://feedsoft.ai/events/45915-how-record-heat-could-affect-the-u-s-corn-and-soybean-markets-dtn.md) | +1.3% | -6.6% |
| SOY | 2026-01-29 | [Heat wave hits Argentina, threatening corn and soybean crops](https://feedsoft.ai/events/13817-heat-wave-hits-argentina-threatening-corn-and-soybean-crops.md) | +1.6% | +6.8% |
| SOY | 2023-07-29 | [Are Farmers Losing Yield? The High Heat's Potential Impact on Midwest's Crops \| Iowa Soybean Research Center](https://feedsoft.ai/events/13266-are-farmers-losing-yield-the-high-heat-s-potential-impact-on-midwest-s-crops.md) | -2.9% | -7.1% |

## Sources

- tuningperu.com: https://tuningperu.com/article/iowa-s-record-breaking-heatwave-impact-on-corn-and-soybean-harvest

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Data from Feedsoft AI (https://feedsoft.ai/). For information only; not investment advice.