UPDATE 1-China June power output rises 5.2 pct

*June power output records first rise in months

*Thermal power output up 3.7 pct, hydro up 7 pct (adds background, graphic link)

BEIJING, July 17 (Reuters) - China's power generation in June increased 5.2 percent from a year earlier, data from the National Statistics Bureau showed on Friday, the first increase in a non-holiday month since October as hotter weather and a reviving economy drove up demand.

Last month's electricity production was at 310.009 billion kilowatt-hours (kWh), of which 240.667 billion kWh was generated by thermal power plants, 3.7 percent higher than the volumes in June 2008.

Output from hydropower plants increased 7 percent from a year earlier to 58.546 billion kWh and production by nuclear power plants rose 6.2 percent to 5.228 billion kWh.

But output in the first half of this year declined 1.7 percent from a year earlier, according to data from the statistics bureau.

(For a historical graphic of monthly power generation, please click: here)

The declines in China's power generation have narrowed in the past several months after near double-digit falls late last year, as consumption gradually picked up, thanks to Beijing's economic stimulus policies.

However, the significance of the first monthly output increase was tempered by the fact that hotter-than-usual weather hit some parts of China in late June, leading to a surge in production late last month.

Temperatures in 10 major cities across the country were mostly above their long-term averages in June, and half of them even above official forecasts, data from the China Meteorological Administration showed.[ID:nPEK174958] (Reporting by Jim Bai and Aizhu Chen; Editing by Chris Lewis)