UPDATE 1-Wal-Mart June sales up; raises earnings forecast

(Adds sales forecast, company comment)

NEW YORK, July 10 (Reuters) - Wal-Mart Stores Inc (WMT.N) on Thursday reported a 5.8 percent rise in June sales at U.S. stores open at least a year, beating Wall Street estimates, and the discount retailer raised its second-quarter earnings forecast.

Analysts, on average, had expected a same-store sales gain of 3.8 percent, according to Thomson Reuters Estimates, while the company itself had forecast a rise of 2 percent to 4 percent, excluding gasoline sales.

Wal-Mart's monthly sales have been outpacing those of competitors as shoppers head to its stores for discounts on food, health-care items and electronics.

Same-store sales rose 6.1 percent at its U.S. namesake discount stores and 4.6 percent at its Sam's Club warehouse division.

"The Wal-Mart U.S. underlying business remains strong," Chief Financial Officer Tom Schoewe said in a statement. "However, consumers and small business owners remain concerned about the economy, inflation and, most of all, higher gas prices."

The retailer said customer traffic at its discount stores rose in the month as shoppers received their U.S. government tax rebate checks. Sales were strongest in its grocery, entertainment and "health and wellness" businesses, which includes medicines.

BOOSTING SECOND-QUARTER FORECAST

Wal-Mart said it now expects second-quarter earnings per share of 82 cents to 84 cents due to "improved sales results during the quarter."