UK GAS-Prompt prices fall on strong wind and warmer weather forecast

Nov 8 (Reuters) - British day-ahead and weekend gas prices fell on Wednesday as forecast warmer weather and stronger wind are expected to curb gas demand, which has been above seasonal average this week, said traders. * Day-ahead gas fell by 0.15 pence to 51.05 pence per therm by 0928 GMT. * The weekend gas price was down 0.10 pence at 51.15 pence per therm. * Expectations for higher wind power output and warmer weather on Thursday, drove the day-ahead price lower, said a british gas trader. "Temperatures are expected to be back above seasonal norms tommorow," she said, justifying the price slip. * Average temperatures on Wednesday could reach 9 degrees Celsius in southern Britain and are expected to grow to 12 degrees on Friday, data from Britain's Met Office showed. * Peak wind power generation is forecast at 6.5 gigawatts (GW) on Wednesday but expected to rise to 7.6 GW on Thursday, Elexon data showed. * Higher wind output typically results in lower demand from gas-to-power plants. * The December contract was up by 0.28 pence at 53.83 pence/therm. * Concerns about the stability of long-term nuclear power supply, could be the reason that curve contracts are seeing a price hike, said another trader. * In France, several nuclear reactor outages have been extended, potentially increasing demand for power in the country. Britain is a key power exporter to France in times of high demand. * In Britain, ongoing planned outages at Britain's Sizewell B-1 and Sizewell B-2 nuclear reactors were also extended. * Britain's gas demand on Wednesday was 7 mcm higher than the seasonal normal demand, National Grid (LSE: NG.L - news) data showed. * Britain's gas system was oversupplied by 12.1 million cubic metres (mcm), with demand forecast at 278.4 mcm and supply at 290.5 mcm/day, National Grid data showed. * Gas supply from Norway to Britain on Wednesday almost reached the pipelines' maximum capacity at 134 mcm/day, down 1 mcm/day from Tuesday. * In the Dutch gas market, the day-ahead gas price at the TTF hub fell by 0.10 euro to 19.15 euros per megawatt hour (MWh). * The benchmark Dec (Shanghai: 600875.SS - news) -17 EU carbon contract fell by 0.04 euro to 7.71 euros a tonne. * Thomson Reuters (Dusseldorf: TOC.DU - news) analyst view: http://emea1.apps.cp.extranet.thomsonreuters.biz/cms/?pageid=united-kingdom-gas (Reporting by Lefteris Karagiannopoulos in Oslo, editing by Louise Heavens)