UK GAS-Prompt falls due to milder weather; strong wind power, LNG feed demand

Nov 20 (Reuters) - Britain's prompt gas prices declined on Wednesday due to milder-than-expected temperatures that are seen rising at the weekend, coupled with strong wind power generation and liquefied natural gas (LNG) supplies.

* Day-ahead gas fell by 0.45 pence to 39.00 pence per therm by 0945 GMT.

* Gas for within-day delivery was 0.25 pence lower at 39.50 pence/therm.

* Milder weather than previously expected, strong wind power generation and expected LNG arrivals led prompt prices lower, despite the system's supply deficit, traders said.

* Average daily temperatures are forecast at 5.6 degrees Celsius on Wednesday and are expected to rise to 7.5 C during the weekend, Refinitiv Eikon data showed.

* Wind power generation is forecast to reach 10.2 gigawatts (GW) on Wednesday and 10.0 GW the next day, Elexon data showed. The system's maximum production capacity is 12.1 GW.

* Strong power generation from wind turbines typically reduces demand for electricity produced in gas-fired plants.

* Five LNG cargos are expected to arrive in Britain this month, with three more vessels set for December.

* The British gas system was undersupplied by around 11.7 million cubic metres (mcm), with demand forecast at 326.5 mcm and supply at 314.8 mcm/day, National Grid data shows.

* Norwegian gas flows rose slightly to 82 mcm per day from 81 mcm on Tuesday, with flows through the Langeled pipeline increasing to 71 mcm/day.

* The December gas contract was up 0.05 pence at 40.05 pence/therm.

* Day-ahead gas at the Dutch TTF hub fell by 0.32 euro to 14.88 euros per megawatt hour (MWh).

* The Dutch month-ahead gas contract, a benchmark for LNG prices as well as European gas, was down 0.10 euro at 15.25 euros/MWh.

* The benchmark Dec-19 EU carbon contract fell by 0.15 euro to 23.29 euros a tonne. (Reporting by Lefteris Karagiannopoulos; Editing by Dale Hudson)