Brazil stocks jump on commodities rally, real up

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SAO PAULO, Aug 21 (Reuters) - Brazilian stocks rose for a third session on Thursday as a surge in oil prices boosted Petrobras, while higher industrial metals boosted shares of mining company Vale and steelmakers Gerdau and Usiminas.

The Bovespa index .BVSP of the Sao Paulo Stock Exchange climbed 1.01 percent to 55,934.69 points. The index is up 4.9 percent since Tuesday in the biggest winning streak since a four-day rally in mid-May drove up stocks by 5 percent.

Crude oil prices jumped more than 5 percent, while industrial metals such as copper and nickel were up as much as 6 percent, a boon to the Bovespa as the most heavily weighted shares in the index are commodity-related.

"Without a doubt, it's commodity prices that set the mood of the day," said Newton Rosa, chief economist at SulAmerica Investimentos.

Brazil's currency, the real BRBY, strengthened 0.62 percent to 1.61 per U.S. dollar on expectations of increased dollar inflows in the coming days as exporters look to repatriate revenue from overseas sales.

The real gained as the dollar slumped globally, pressured by persistent worries over the U.S. financial sector and the surge in oil prices. The U.S. dollar index .DXY, a gauge of its value against a basket of six major currencies, posted its worst one-day fall in several months.

On the stock exchange, shares of oil giant Petrobras (PETR4.SA: Quote, Profile, Research, Stock Buzz) jumped 3.45 percent to 35.39 reais tracking the biggest one-day rally in crude prices in more than two months as tensions between the United States and Russia grew. Petrobras is the top-weighted stock in the Bovespa index.

Vale (VALE5.SA: Quote, Profile, Research, Stock Buzz), one of the world's largest diversified mining companies, gained 2.4 percent to 38.8 reais as a weaker U.S. dollar sparked a rally in dollar-denominated commodities prices. Vale is the second most heavily weighted stock in the Bovespa.

The surge in metals prices also boosted shares of Brazilian steelmakers, with Usiminas (USIM5.SA: Quote, Profile, Research, Stock Buzz) up 3.4 percent to 56.85 reais and Gerdau (GGBR4.SA: Quote, Profile, Research, Stock Buzz) rising 3.1 percent to 29.99 reais.

Common shares of state-controlled electricity generator Eletrobras (ELET3.SA: Quote, Profile, Research, Stock Buzz) gained 3 percent to 29.4 reais. The company said in a securities filing on Thursday it is in final negotiations with the federal government to make past due dividend payments owed to holders of common shares. UBS Pactual said in a report the dividend payments were "very positive news" for the shares.

Interest-rate futures <0#DIJ:> at the BM&F commodities and futures exchange in Sao Paulo were mixed, ahead of the release of benchmark inflation data on Friday. A Reuters survey of 30 economists showed the IPCA inflation index should rise 0.38 percent in the month-long period through mid-August, slowing from 0.63 percent in the month to mid-July. (Reporting by Elzio Barreto and Rodolfo Barbosa; Editing by Leslie Adler)