By Jesse Newman

CHICAGO--Soybean futures dropped to a one-month low, pressured by crop-friendly rains in Argentina, while a stronger dollar weighed broadly on agricultural commodities.

Prices for soybeans fell to the lowest level since Nov. 18 as recent rainfall and forecasts for ongoing precipitation eased worries over production problems in that country. South America is a key U.S. rival for soybean production and export, and better weather there could mean more competition for U.S. shipments. Argentina is slated to get a half-inch to 2 inches of rain this week, analysts said.

Weaker prices for soybean meal and soyoil, which are made from the crop, also weighed on the oilseed market, as did speculation that U.S. farmers will ramp up soybean plantings next spring. A firmer U.S. dollar and end-of-the-year selling by commodity funds further pressured the market.

"You have some serious weight on [soybean] prices now," said Charlie Sernatinger, head of grain trading at ED&F Man Capital Markets in Chicago.

Soybean futures for January slid 16 1/4 cents, or 1.6%, to $10.05 1/4 a bushel at the Chicago Board of Trade.

Corn and wheat prices moved lower for a second-consecutive session, buffeted by the firmer dollar, which hit a fresh 13-year high overnight. An ascendant dollar acts as a weight on agricultural markets because it makes U.S. farm goods less affordable for foreign buyers.

Meanwhile, good rains in Argentina are also expected to improve the health of that country's corn crop, boosting the outlook for production at a time when world corn inventories are already at all-time highs.

CBOT March corn futures declined 3 cents, or 0.9%, to $3.50 1/4 a bushel.

The wheat market suffered due to forecasts for warmer U.S. temperatures over the next two weeks, although losses were stemmed by a colder outlook for January. Bitterly cold temperatures can damage wheat crops that aren't sufficiently insulated from the snow.

CBOT March wheat futures shed 1 3/4 cents, or 0.4%, to $4.03 1/4 a bushel.

Write to Jesse Newman at jesse.newman@wsj.com

(END) Dow Jones Newswires

December 20, 2016 16:19 ET (21:19 GMT)

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