A week that opened with heat stress and weak positioning ended with wheat posting its sharpest gains in months, as intensifying Black Sea port attacks, a sixth night of US-Iran strikes, and a fresh 25% tariff on Brazilian imports converged to keep volatility elevated across wheat, corn, and soybeans.

Grain markets moved through one of the more volatile stretches of the year, with wheat swinging from a five-cent loss Monday to a near-limit, 34-cent rally by Wednesday as Black Sea shipping risk overtook every other driver in the complex, while corn and soybeans spent the week caught between supportive production cuts and persistently soft export demand.

Black Sea Risk Intensifies by the Day

Black Sea escalation was the defining theme of the week and only intensified as the days passed. Russian exports through the Kerch Strait remained restricted for a second straight week, with vessels able to cross the Sea of Azov but unable to exit into the Black Sea, and Russia's Union of Grain Exporters insisted it could still meet commitments by rerouting cargoes even as the market stayed skeptical given the shortage of operational vessels. The conflict turned sharply more destructive by midweek, with Russia striking port locations in Odesa in retaliation for Ukrainian attacks on tankers in the Sea of Azov, and by Friday Ukrainian forces claimed to have hit 159 Russian vessels across the Black Sea and Sea of Azov over just eleven days, with Chornomorsk sharply curtailing intake after repeated strikes. SovEcon and IKAR both cut their Russian wheat export forecasts for July to 2 MMT or lower, well under the 4-6 MMT typically shipped during the August-October peak, a supply disruption from the world's top wheat exporter that kept the path of least resistance pointed higher all week.

Middle East Conflict Adds a Second Layer of Pressure

The Middle East conflict added a second, compounding layer of pressure. US and Iranian forces exchanged strikes over the prior weekend, with Iran again declaring the Strait of Hormuz closed while Washington maintained the waterway remained open to commercial traffic; by Friday, US Central Command had struck Iranian targets for a sixth consecutive evening, with Iran claiming retaliatory strikes on US forces in Syria and Bahrain. Spot WTI crude climbed from near $74 per barrel Monday to within reach of $81 by Friday, dragging RBOB and heating oil higher alongside it and feeding directly into the biofuel-linked strength that showed up in soybean oil late in the week.

US Crops Stay on Pace Despite the Heat

US crop development stayed mostly on schedule despite the heat. Winter wheat harvest reached 67% by Sunday, six points ahead of normal, while corn was 34% silked against a 30% five-year average and soybeans were 50% blooming versus a 44% average, with condition ratings holding at 68% good-to-excellent for corn and 65% for soybeans, both roughly in line with expectations. Temperatures above 105°F scorched the Northern Plains and northwestern Corn Belt over the opening weekend, but the market largely discounted the damage as forecasts pointed to easing heat by the weekend's end, even as the Western Corn Belt continued running dry with little relief expected into next week.

Export Demand Falls Short

Thursday's weekly USDA Export Sales report delivered a broadly disappointing demand picture that briefly tested the rally's legs. Wheat sales of just 235,102 MT for the week of July 9 marked the lowest tally of the new marketing year and less than half of the same week a year ago; corn old-crop sales of 314,962 MT missed low-end estimates while new-crop bookings hit a six-week low; and soybean old-crop sales of 188,274 MT were down nearly 31% year-over-year, though new-crop business of 1.77 MMT posted a marketing-year high on the back of Chinese buying. The soft numbers were not enough to derail wheat's Black Sea-driven momentum, but they did cap follow-through buying in corn into Friday's open.

Wheat and Corn Supply Estimates Slip Further

Global production estimates shifted lower across several origins even as the IGC held its world wheat forecast unchanged at 821 MMT. France's Farm Ministry projected 2026 soft wheat output at 32 MMT, down 4% on the year as a 7% yield cut outweighed a 3% increase in planted area, while a German farm co-op projected domestic wheat production down 5.6% to 42.7 MMT. Corn fared worse: the IGC cut its 2026/27 world production forecast by 4 MMT to 1.306 billion tonnes, driven largely by a 3 MMT reduction to the French crop, whose condition rating collapsed to 41% good-to-excellent by Friday, down six points on the week and far below last year's 72%.

South America Adds Supply as China Buys Record Volumes

South America continued to add supply even as Chinese demand hit fresh records. CONAB raised Brazil's 2025/26 soybean crop to 180.57 MMT and its corn crop to 141.73 MMT, while ANEC lifted its July corn export estimate to 3.44 MMT and its soybean export estimate to 13.76 MMT, both well above year-ago levels. China's June soybean imports reached an all-time high of 13.55 MMT, up 15% from May, though Argentine farmers had priced only 28% of this year's crop by mid-July, below the 35% historical average, a slow pace of selling that could tighten near-term deliverable supply.

Crush Data and Biofuel Demand Support Soybean Oil

The soybean complex found an additional demand pillar from biofuels. NOPA members crushed a record 214.3 million bushels of soybeans in June, roughly 10 million above expectations, yet soybean oil stocks fell to an eight-month low of 1.5 billion pounds, pointing to a genuine surge in domestic oil usage rather than a production shortfall. That surge was corroborated Friday by EPA data showing D4 RIN generation reaching 839 million in June, up 14% from May and the highest level since December 2024, a signal of accelerating biodiesel and renewable diesel output that helped soybean oil touch a five-week high into the week's close. Corn's ethanol grind told the opposite story, slumping to just 306 million gallons for the week, the lowest in ten weeks and the thirteenth consecutive week running below the pace needed to hit the USDA's usage forecast.

Brazil Tariff and Shifting Fund Positioning

A fresh trade headline added a further layer of uncertainty late in the week. The USTR confirmed a 25% tariff on Brazilian imports under Section 301, set to take effect July 22 and extending to ethanol and sugar, with exemptions carved out for beef, coffee, rare earths, energy products, and aircraft parts; Brazil's response remained pending, and the market had yet to fully price the potential knock-on effects for global soybean and product flows. Fund positioning shifted meaningfully over the week as well, with speculative wheat shorts in Chicago SRW falling from near 50,000 contracts Monday to roughly 33,000 by Friday, while money managers flipped to net long in corn early in the week on 59,000 contracts of buying, a combination that left the complex more exposed to further short covering on any additional bullish headline.

Wheat: Black Sea Risk Fuels the Week's Sharpest Rally

Wheat posted the most dramatic swing of the week, closing Monday at $6.35 1/4 on Sept '26 CBOT before firming to $6.45 Tuesday and then exploding 34 1/4 cents higher Wednesday to $6.79 1/4, with KC HRW briefly locking at its 45-cent daily limit as Black Sea attacks intensified. The rally cooled modestly Thursday, with Sept '26 closing at $6.74 3/4, down 2 3/4 cents, before the complex shrugged off that weakness Friday to open $0.02 to $0.06 higher across all three classes near $6.93 in Chicago. The dominant theme throughout was Black Sea supply disruption compounding with lower US, French, and German production estimates, a combination that kept volatility elevated and the path of least resistance tilted higher all week.

Corn: Riding Wheat's Coattails, Capped by Soft Demand

Corn tracked wheat's momentum for much of the week, with Sept '26 rallying to a fresh six-week high of $4.47 1/2 at Wednesday's close on spillover support and the IGC's production cut, before easing to $4.41 1/2 Thursday and opening $4.40 1/2 Friday, down a cent and holding within the week's range. The dominant theme was a tug-of-war between bullish production cuts in France and the Black Sea-driven wheat rally on one side, and a persistently weak ethanol grind alongside soft export sales on the other, leaving corn more range-bound than its wheat counterpart despite similar underlying supply pressure.

Soybeans: Choppy Trade Around the $12 Level

Soybeans spent the week oscillating around the psychologically important $12 level, with Aug '26 dipping to $11.90 Wednesday morning before rallying to close above $12 for the first time in two months at $12.01, then opening as high as $12.05 1/2 Thursday before slipping back to close at $11.95 and opening $11.97 1/2 Friday. The week's dominant theme was a split narrative between record NOPA crush data and surging biofuel-driven soybean oil demand on the supportive side, against a newly confirmed Brazil tariff and choppy Chinese demand signals on the uncertain side, keeping the contract capped just below the $12 resistance level heading into the weekend.