(Updates U.S. market activity to close)
By Michael Hirtzer
CHICAGO, Dec 9 (Reuters) - U.S. soybean and corn futures rose 1 percent on Friday, buoyed by technical buying and concerns over dry growing conditions in Argentina in the wake of U.S. Department of Agriculture crop data at midday that was deemed neutral, traders said.
Wheat futures also rallied at the Chicago Board of Trade, with all three commodities adding to gains late in the session.
CBOT corn led the way higher, with the most-active March futures contract finishing up 6 cents at $3.59-1/2 per bushel and surpassing several key moving averages. Corn for the week jumped 3.3 percent, its largest weekly gain since October.
Soybeans for January delivery were 10-1/2 cents higher at $10.37-1/2 per bushel, rising 1.1 percent for the week and recovering from an earlier two-week low.
The gains came after USDA in a monthly report left U.S. soybean, corn and wheat stockpile estimates unchanged and hiked global stockpiles to account for bigger corn production in Brazil and wheat output in Australia.
"Corn ignored a bearish world supply and demand from the USDA and rallied on continued concern about dryness in southern Argentina and firmer petroleum prices," ED&F Man Capital analyst Charlie Sernatinger said in a note to clients.
The Commodity Weather Group said rainfall was likely to be limited next week in Argentina, although extended outlooks for precipitation within the next 10 days could help alleviate dry conditions there.
The USDA put U.S. soybean ending stocks at 480 million bushels, unchanged from its estimate in November and 10 million bushels above the analysts' average estimate from a Reuters survey.
U.S. corn ending stocks were seen at 2.403 billion bushels, 10 million below analysts' estimates, with U.S. wheat pegged at 1.143 billion bushels, 4 million above market expectations.
The USDA's December monthly outlook typically has fewer changes than data due in January, which will include final U.S. crop production figures for the 2016-17 growing season as well as quarterly grain stocks.
CBOT March wheat futures settled 8 cents higher at $4.16-1/4 per bushel, bringing the week's gains to 2.2 percent.
The Commodity Futures Trading Commision after the close of trading said speculative investors, including hedge funds, increased their net short or bearish positions in CBOT corn and wheat futures and slashed their net long in soybeans in the week ended Dec. 6. (Additional reporting by Mark Weinraub in Washington, Theopolis Waters in Chicago, Naveen Thukral in Singapore and Gus Trompiz in Paris; Editing by Lisa Von Ahn and James Dalgleish)