2012: the US drought that took a quarter off the corn crop — then the market took it back
Jun – Sep 2012
The lesson: The sharpest single-season corn shock on record sent CBOT corn futures up more than a fifth in six months — then a normal 2013 season erased the entire spike within a year. Weather moves the price; the next harvest moves it back.
What happened
The fastest-planted corn crop on record met a brutal summer. On 11 Jul 2012 USDA's World Agricultural Outlook Board cut the US corn crop estimate by 1.82 billion bushels — about an eighth — in a single month, citing 'persistent and extreme June and early-July dryness and heat'; nearly four-fifths of US corn acreage sat inside drought areas (USDA, 12 Jul 2012). The 10 Aug Crop Production report put yield at 123.4 bushels per acre, down almost 24 from 2011 and the lowest since 1995/96, with production of 10.8 billion bushels, down about an eighth from 2011 — despite the most corn acres planted in 75 years. The final tally was 10.78 billion bushels, less than three-fourths of the spring forecast (AP, Jan 2013). No US export restrictions were imposed; the market rationed by price.
- United States (Iowa corn belt centroid) (May-Oct 2012): +1.38°C vs the 1991–2020 baseline; rainfall -34.7% vs baseline (140 days with <1mm rain). The 2012 growing season ran hot and dry at this Iowa centroid: +1.4 C vs baseline, rainfall about a third below normal, with 140 of 184 days recording under 1mm of rain.
One region centroid is illustrative, not field-level truth; baseline is the 1991–2020 day-of-year mean. Weather data provided by Open-Meteo.com.
What everyone expected
CBOT corn was 'soaring to over $8 a bushel on July 23 (from $6 at the end of June) with projections from Goldman Sachs that it could reach $9 per bushel in three months' (Union of Concerned Scientists, Jul 2012). The Kansas City Fed warned the drought could add about four percent to annual food prices over the next year.
As reported at the time: Union of Concerned Scientists, Jul 2012 · Kansas City Fed via Weather Channel, Aug 2012
What actually happened
- Corn2012-02 → 2012-08 · ZC=F month-end closes+22.3%
The run-up into the August peak.
- Corn2012-06 → 2012-08 · ZC=F month-end closes+19.4%
Two months, a fifth higher.
- Corn2012-08 → 2013-08 · ZC=F month-end closes-38.3%
One normal season later, the whole spike was gone.
Month-end closes smooth the intraday peak — $8.49 per bushel on 10 Aug (Fast Company) — so the monthly series understates the panic high. The year-later decline mixes drought recovery with a large 2013 planted area.
The assessment
The production shock was genuine — the largest single-season US corn yield loss of the modern era — and futures priced it within weeks. Three absorbers capped the damage: no exporter panicked into bans, demand rationed fast (the EIA recorded corn up more than a third between mid-June and late August as ethanol margins collapsed), and the 2013 crop was normal. The BLS noted consumers barely felt it: grocery food prices advanced just two-tenths of a percent in the drought months. Farm-gate spikes and grocery spikes are different events.
How this record has changed
Living document — every material change is logged here, newest first.
- New evidence2026-09-17
Added ERA5 weather reanalysis context for May-Oct 2012 at the Iowa corn belt centroid: +1.38 C mean temperature anomaly vs the 1991-2020 baseline, rainfall 34.7% below normal, 140 of 184 days under 1mm. Derived from Morrowfly's research vintage v1_2026-09-15 (raw daily series stay in research; only derived anomalies shown). Attribution: weather data provided by Open-Meteo.com.
Morrowfly research vintage v1_2026-09-15 + 2026-09-17 window addendum (ERA5 reanalysis via Open-Meteo)
- Correction2026-09-15
Seed revision marking this record as published under the adversarial-review standard established 2026-09-15: outcome figures recomputed from Morrowfly's own month-end price history, intraday peaks confined to mechanism prose, and no bare '%' figures in narratives. Applied at creation, before any public revision.
Morrowfly internal adversarial review standard (15 Sep 2026)
Transmission
- production loss
The US is the top corn exporter; the drought cut the US crop by about a quarter from spring expectations (USDA NASS, Aug 2012; AP final report, Jan 2013).
Sources
- USDA NASS · 10 Aug 2012 · U.S. Growers Expect to Produce 13 Percent Less Corn than Last Year
- USDA · 12 Jul 2012 · Agricultural Weather and Drought Update – 7/12/12
- USDA ERS · 17 Aug 2012 · As drought continues, forecast yield for corn is lowered 23 bushels per acre
- AP via Food Manufacturing · 11 Jan 2013 · Drought Cut Corn Crop by 25 Percent
- EIA · 31 Aug 2012 · Drought increases price of corn, reduces profits to ethanol producers
- BLS · Dec 2012 · Will the 2012 drought have a bigger impact on grocery prices than the 1988 drought?
- Union of Concerned Scientists · 24 Jul 2012 · The Enormous Costs of the 2012 Drought to American Farmers and Taxpayers
Notes
- Prices are month-end closes from our series unless noted; windows are labeled beside each number.
- Secondary press quotes are reported as published and were not individually audited against primary sources.
- Illustrative scenario record. Not a prediction. Not financial advice.