GRAINS-Soybeans, meal rise on Argentina weather; corn turns lower

(Updates prices, adds analyst comments; changes byline, dateline, previous SINGAPORE/PARIS)

CHICAGO, Dec 4 (Reuters) - U.S. soybean futures rose to a three-week high on Monday and soymeal jumped more than 2 percent on buying backed by concerns that dry weather in Argentina will hurt crop yields.

Corn futures fell about 1 percent, reversing from early gains on technical selling, while wheat futures were narrowly mixed on the Chicago Board of Trade.

Soymeal was on pace to notch its largest daily gains since October, with the most-active CBOT January contract up $6.50 to $336.70 per ton at 11:31 a.m. CST (1731 GMT). CBOT January soybean futures climbed 3 cents, or 0.3 percent, to $9.97-1/4 per bushel, highest since Nov. 7.

Rainfall over the weekend was limited in parts of Argentina, the top global soymeal and soyoil exporter, and showers were expected to be limited this week, MDA Weather Services said in a note to clients.

"Meal is the deal," said EFG Group analyst Tom Fritz, adding that U.S. soymeal was competitively priced with Argentine supplies in global markets.

Additionally, U.S. Department of Agriculture data released after the close of trading on Friday showed the U.S. soy crush in October at about 176 million bushels, above analysts' estimates and a reflection of strong domestic soy demand.

CBOT March corn was down 3-3/4 cents to $3.55 per bushel, after hitting a multiweek high of $3.60-1/2.

"We challenged resistance and balked," Fritz said of corn.

CBOT March wheat was down 1/4 cent to $4.38-1/4, also declining after earlier gains.

Concerns over storms damaging Australia's wheat crop eased after less-than-expected rain over the country's southeastern region.

"The market's fears about several days of heavy rainfall in south eastern crop regions were clearly subsiding on Friday," said Tobin Gorey, director of agricultural strategy at Commonwealth Bank of Australia. "And these regions seem to have received a lot less rain than was feared on Wednesday and Thursday last week."

Large speculators trimmed their net short position in Chicago Board of Trade corn futures in the week to Nov. 28, regulatory data released on Friday showed.

The Commodity Futures Trading Commission's weekly commitments of traders report also showed non-commercial traders, a category that includes hedge funds, increased their net short position in CBOT wheat and switched to a net long position in soybeans.

(Additional reporting by Sybille de La Hamaide in Paris and Naveen Thukral in Singapore; Editing by Dan Grebler)