UK GAS-Prices rise on cooler weather, stronger oil

* Wind power output seen at 6.4 GW on Wednesday

* Gas system oversupplied by 12 mcm

April 6 (Reuters) - British prompt gas prices rose on Wednesday as lower temperatures boosted gas demand for heating, while longer-term contracts got support from stronger oil prices.

Gas for immediate delivery rose by 0.58 pence to 27.48 pence per therm by 0900 GMT, while the day-ahead contract gained 0.15 pence to 27.85 pence/therm.

Maximum temperatures are expected to fall to 11 degrees Celsius on Thursday from 13 degrees on Wednesday in London and southeast England, forecasts from the UK's Met Office showed.

The increase in prices, however, was capped by a comfortable supply situation.

With (Other OTC: WWTH - news) gas supply flows at around 266 million cubic metres (mcm) and demand expected to be around 254 mcm, Britain's gas system was 12 mcm oversupplied, National Grid (LSE: NG.L - news) data showed.

Rising supplies from Norway and liquefied natural gas terminals have resulted in oversupply, traders said.

Higher gas demand for heating was also partly offset by strong winds reducing gas use for power generation.

Peak wind power output was expected to reach 6.4 gigawatts (GW) on Wednesday compared with total installed capacity of 8.9 GW, National Grid data showed.

Gas demand for power generation rose by some 1.6 billion cubic metres (bcm) or 48 percent year-on-year during the first quarter of 2016, London-based consultancy Energy Aspects said in a note on Wednesday.

Over the summer, gas demand from the power sector is expected to rise by 4.8 bcm year-on-year, it added.

Longer-term contracts were lifted by stronger oil prices on Wednesday. The contract for gas delivery next quarter was up by 0.15 pence to 26.50 pence/therm.

Crude futures jumped on Wednesday over a U.S (Other OTC: UBGXF - news) . dollar to a high of $36.92 per barrel, as hopes for an agreement among exporters to freeze output underpinned the market.

In the Dutch gas market, the day-ahead price at the TTF hub rose by 0.05 euro per megawatt hour to 11.40 euro/MWh. In the European carbon market, front-year EU allowances firmed 0.05 euro to 5.29 euros a tonne. (Reporting by Nerijus Adomaitis; editing by Nina Chestney)