Soybeans jump as inclement South American weather stokes supply woes

(Adds closing prices and details about crops in Argentina and Ukraine)

* Hot, dry weather expected to stress Argentina soy

* Rains delay Brazil soy harvest

* Weekly U.S. corn export sales miss expectations

CHICAGO, March 4 (Reuters) - U.S. soybean futures settled higher on Thursday as adverse weather across South America fueled concerns about a short-term supply crunch.

The market briefly turned lower late in the trading session amid gains in the U.S. dollar that make American farm goods less attractive to importers, traders said.

Prices then rose again as unfavorable dryness in Argentina and excessive rains in Brazil reinforced supply concerns.

The Buenos Aires Grains Exchange said it could cut its harvest forecast for 2020/21 soy production in Argentina, the world's top soymeal exporter, if it does not rain sufficiently in key producing areas over the weeks ahead.

The U.S. Department of Agriculture will update its estimates on global supplies in a monthly report due on Tuesday. Record U.S. soybean crushings and exports are already projected to shrink U.S. soybean stocks to a mere 9-1/2 day supply ahead of the next North American harvest.

"With the market looking for a possible hot and dry weather stress in Argentina or for the USDA to further tighten U.S. old-crop ending stocks, the trade needs a bullish punch to up prices," said Jerry Gidel, analyst for Midland Research.

The most-active Chicago Board of Trade soybean contract ended up 3 cents at $14.10-1/2 a bushel, after reaching a session high of $14.38. The most-active contract last week reached $14.45-3/4 a bushel, the highest price since June 2014.

The USDA, in a weekly report, said U.S. soybean export sales totaled 533,400 tonnes for the week ended on Feb. 25, within analysts' estimates for 100,000 to 800,000 tonnes.

Weekly U.S. corn export sales totaled 154,700 tonnes, well below analysts' estimates for 450,000 to 1.05 million tonnes.

In Ukraine, meanwhile, exporters could boost grain shipments in the July-June season as harvests may reach a record high, the deputy economy minister in charge of agriculture said.

Most-active CBOT corn futures slipped 2-3/4 cents to $5.32-1/2 a bushel, while wheat ended down 5 cents at $6.51 per bushel. (Reporting by Tom Polansek in Chicago, Colin Packham in Sydney and Sybille de La Hamaide in Paris; Editing by David Goodman and Dan Grebler)