* Only 12 pct of those surveyed see jobless rate rising
* Americans more upbeat on prospects for economy
NEW YORK, Sept 14 (Reuters) - Consumer confidence unexpectedly improved in early September as Americans anticipated better economic and employment prospects, but the cheery attitudes could be temporary, a survey showed on Friday.
The Thomson Reuters/University of Michigan's preliminary September consumer sentiment index rose to 79.2 from 74.3 in August. That topped expectations for a decline to 74.0, according to a Reuters poll.
The gauge of consumer expectations climbed to 73.4 from 65.1, though the barometer of current economic conditions nudged down to 88.3 from 88.7. Both the sentiment and expectations measures were at their highest levels since May.
Just 12 percent of those surveyed expected the unemployment rate to rise, down sharply from the 25 percent who anticipated an increase in August's survey. This month's proportion was the lowest recorded since 1966.
Favorable long-term prospects for the economy were seen by 42 percent of consumers, the highest level in five years and up from 32 percent last month.
But the improved optimism was likely a temporary bounce after the recent presidential candidate conventions, the report cautioned, noting that last month's employment figures had been disappointing.
"The sooner it is tempered, the less economic damage will be incurred due to failed expectations," survey director Richard Curtin said in a statement.
Consumer spending will likely rise on average about 1.8 percent from the fourth quarter of this year to the first quarter of 2013, Curtin said.
Consumers also felt better about their personal finances, with 37 percent reporting a worsening financial situation, down from 40 percent, as Americans continued to whittle down debt.
Still, 61 percent expected their financial situation to remain unchanged in the year ahead, the largest proportion in the history of the survey.
While rising food and gasoline prices remained a concern, the one-year inflation expectation eased to 3.5 percent from 3.6 percent. The five-to-10-year inflation outlook also pulled back to 2.8 percent from 3.0 percent.
Cheap mortgage rates bolstered Americans' opinions on the housing market with 80 percent saying home-buying conditions were favorable, up from 71 percent a year ago.
There was little reaction by financial markets to the report as Thursday's aggressive move by the Federal Reserve to stimulate the economy continued to dominate trade.
Government data on Friday showed retail sales rose for a second month in a row in August, but the details of the report pointed to only a modest increase in consumer spending in the third quarter.