UK GAS-Day ahead prices flat on oversupplied system

LONDON, April 10 (Reuters) - British wholesale day-ahead gas prices were flat on Monday morning on an oversupplied system, as Norwegian gas flows fell and temperatures dropped from the weekend levels. * British day-ahead gas price were flat at 39.40 pence per therm at 1025 GMT. * The within-day contract fell by 0.80 pence to 39.25 p/therm. * 'Day ahead prices are stable because the system is oversupplied' despite colder weather and lower Norway flows, said Katrina Oldham, a trader from British Inenco Ltd. * Britain's Met Offices forecast temperatures could reach as high as 13 degrees Celsius in the southeast of the country on Monday and are expected to remain mostly stable over the rest of the week. * Peak wind power output forecast at 6.3 gigawatts (GW) for Monday, climbing to 7.0 GW on Tuesday compared with total capacity of around 10 GW, National Grid (LSE: NG.L - news) data showed. * Gas demand, at 235 million cubic meters (mcm) was lower than the seasonal norm of 241 mcm, National Grid data showed. * System oversupplied with demand forecast at 235.0 million cubic meters (mcm) and flows at 253.5 mcm/day, National Grid data shows. * Total (LSE: 524773.L - news) gas imports from Norway fell by 10 mcm to 321 mcm, mostly due to reduced flows from the Langeled pipeline, which fell by 13 mcm to 34 mcm from Friday. * British nuclear reactor Torness 1 went offline on Friday on a planned outage, reactor Hinkley Point B8 came back on Monday morning. * May gas contract (TRGBNBPMK7 ) up by 0.15 pence at 39.20 p/therm. * Day-ahead gas price at the Dutch TTF hub up by 0.25 euro at 15.85 euros per megawatt hour. * Benchmark Dec-17 EU carbon contract down by 0.03 euro to 4.86 euros per tonne. * Thomson Reuters (Dusseldorf: TOC.DU - news) analyst view: http://emea1.apps.cp.extranet.thomsonreuters.biz/cms/?pageid=united-kingdom-gas