UK GAS-Prompt prices fall on reduced demand, oversupply

(Adds within day price after starts to trade; updates prices)

LONDON, Sept 10 (Reuters) - British prompt wholesale gas prices fell on Tuesday morning as reduced demand helped to create an oversupplied market, while contracts further out on the curve gained ground.

* Day-ahead gas fell by 1.35 pence to 24.75 p/therm by 0739 GMT.

* Gas for immediate delivery was 0.60 p lower at 24.90 p/therm.

* Demand is forecast at 154 million cubic metres (mcm) and flows at 163.5 mcm/day, meaning the system is oversupplied by nearly 10 mcm, National Grid data shows.

* Local heating consumption and gas-for-power demand are seen lower than yesterday.

* Peak wind generation is forecast at 8.5 megawatts on Tuesday, rising to 11.6 GW on Thursday, Elexon data shows, out of a total metered capacity of nearly 12.1 GW.

* Strong wind output typically reduces demand from gas-to-power plants.

* Temperatures are also forecast slightly higher for the rest of the week compared to Monday.

* Further out on the curve, prices rose.

* Winter 2019 was 0.16 p up at 45.26 p/therm. October gas was 1.30 p higher at 33.10 p/therm.

* Flows through the Langeled pipeline from Norway are at zero as the Easington terminal is shutdown for planned maintenance until Sept. 24.

* In the Dutch gas market, the day-ahead gas price at the Dutch TTF hub inched down 0.02 euro to 9.50 euros per megawatt hour.

* Benchmark Dec-19 EU carbon contract was 0.58 euro higher at 25.60 euros a tonne. (Reporting by Nina Chestney)