* Source says car and light truck sales show best June ever
* Tax break, incentives help bring first half in line yr/yr
SAO PAULO, July 2 (Reuters) - Brazilian auto sales jumped to their best June ever, an industry source with access to sales data said on Monday, as tax breaks and lending incentives helped bolster a flagging car industry.
Sales of cars and light trucks advanced 24 percent in June from May to about 340,300 vehicles, according to the source, up 19 percent from a year earlier. Last month's surge brought sales in the first half to 1.6 million vehicles, nearly even with the first half of 2011.
Daily sales volumes averaged around 17,000 vehicles in June, according to Thomson Reuters calculations, the strongest pace since November. Sales picked up from less than 13,000 per day in the first five months of the year.
Brazil's auto market had contracted nearly 5 percent through May, as rising household debts and tighter lending weighed on demand, pushing automaker inventories to almost four-year highs.
Carmakers have said consumers responded immediately to the government stimulus at the end of May, cutting an industrial tax on some vehicles and freeing up bank deposit requirements in exchange for sweetened terms for auto loans.
The June rebound surpassed several analysts' projections and could bolster some of the world's largest automakers with operations in the country. The top carmakers in Brazil include Italy's Fiat SpA, Germany's Volkswagen AG and U.S.-based General Motors Co and Ford Motor Co.