UK GAS-Prices fall on higher Norwegian flows, wind power output

May 4 (Reuters) - British wholesale gas prices fell on Thursday morning as Norwegian flows and wind power output increased and crude oil prices fell. * The British day-ahead gas price fell by 0.90 pence to 41.00 pence per therm by 0846 GMT. * The within-day contract was flat at 41.00 p/therm. * The system was oversupplied by 5.5 million cubic meters (mcm), with demand forecast at 231.1 mcm and flows at 236.6 mcm/day, National Grid (LSE: NG.L - news) data showed. * "The gas system is long; there's a lot of wind as well " a UK gas trader said. * Imports from Norway through the Langeled pipeline rose to 61 mcm/day from around 56 mcm/day overnight. * Thomson Reuters (Dusseldorf: TOC.DU - news) gas analyst Oliver Sanderson said Norwegian exports have been boosted by the end of some maintenance at Kollsnes gas processing plant. * However, more Norwegian maintenance is expected from May 6. * "We expect Langeled (pipeline flows) to fall toward 25 mcm during the period May 6-9 and 15-19," Sanderson said, adding that an expected shutdown of the Ormen Lange field between May 10 and 14 will lower Langeled flows to around 10 mcm/d. * Peak wind power output is forecast at 7.0 gigawatts (GW) on Thursday, falling to 5.8 GW on Friday, National Grid data shows. * Temperatures on Thursday will reach 14 degrees Celsius in southern Britain, and rise to up to 16 degrees over the weekend, UK's Met Office data showed. * In the power market, four of Britain's nuclear reactors are offline, totalling 2,295 megawatts of capacity. * The June gas contract fell by 0.23 pence at 38.60 p/therm. * Crude oil lost ground on Thursday, falling for a third out of four sessions and trading near its lowest since late March after data showed a lower than expected decline in U.S. inventories. * Day-ahead gas price at the Dutch TTF hub was down by 0.20 euro at 16.40 euros per megawatt hour. * Benchmark Dec-17 EU carbon contract was down by 0.05 euro at 4.35 euros per tonne. * Thomson Reuters analyst view: (Reporting by Lefteris Karagiannopoulos in Oslo; editing by Nina Chestney)