The Standard & Poor’s GSCI gauge of 24 raw materials rose 0.3 percent to settle at 620.15 in New York Thursday, led by grains.

Corn futures jumped to a nine-month high and soybeans reached the highest since July 2008 as a heat wave and drought threatened to limit output in the U.S., the world’s top exporter. Wheat rose to a 14-month high.

The National Weather Service issued excessive heat warnings from Idaho to Ohio. As of July 3, 53 percent of the Midwest had moderate to extreme drought conditions, compared with none a year ago, the U.S. Drought Monitor showed.

On the Chicago Board of Trade, corn futures for December delivery advanced 5 percent to $7.085 a bushel. Earlier, the price reached $7.13, the highest for the most-active contract since Sept. 15.

Soybean futures for November delivery rose 3.5 percent to $15.265 a bushel. The oilseed reached $15.29, the highest since July 2008.

Wheat futures for December delivery gained 4.8 percent to $8.38 a bushel. The grain reached $8.4075, the highest since April 2011.

NATURAL GAS

Natural gas advanced to a six-month high amid speculation that government data will show a smaller-than-normal increase in stockpiles for last week because of hot weather.

On the New York Mercantile Exchange, gas futures for August delivery rose 1.6 percent to $2.945 per million British thermal units, the highest settlement since Jan. 9.

U.K. gas rose as Statoil ASA said it is preparing to shut output on Norway’s continental shelf as employers lock out striking workers.

Gas for next week climbed 1 pence, or 1.7 percent, to 58.5 pence a therm at 4:07 p.m. London time. August gas gained 1.2 percent to 57.45 pence a therm. That’s equivalent to $8.92 per million Btu. A therm is 100,000 Btu.

CRUDE OIL

Crude oil dropped after the dollar rose against the euro as European Central Bank President Mario Draghi said economic risks remain after the bank cut rates to a record.

On the Nymex, oil futures for August delivery 0.5 percent to $87.22 a barrel.

Brent oil for August settlement advanced 0.8 percent to $100.55 a barrel on the London-based ICE Futures Europe exchange.

Total SA bought two cargoes of North Sea Forties after the blend rose to a one-month high, while Eni SpA failed to buy Russian Urals crude in the Mediterranean at a higher price. Nigerian Qua Iboe’s premium to Dated Brent dropped to a 25-month low.

Norwegian oil producers led by Statoil ASA plan to shut all offshore operations next week as western Europe’s largest crude exporter seeks to resolve an 11-day strike over pensions.

OIL PRODUCTS

Gasoline gained to a five-week high as Brent crude rose after Norway’s largest oil producer said a strike forced a production halt and U.S. motor fuel demand climbed last week before the July 4 holiday.

On the Nymex, gasoline futures for August delivery rose 1.5 percent to $2.7648 a gallon.

Heating-oil futures for August delivery climbed 0.4 percent to $2.7684 a gallon.