UK GAS-Spot prices drop as milder temperatures temper demand

* Within-day gas down 0.3 p/therm to 31.40 p/therm

* Warmer weather trend weighs on prices

April 29 (Reuters) - British gas prices fell on Friday as consumption levels declined in line with slightly milder temperatures and an adequately supplied transmission network.

Gas for instant delivery fell 0.30 pence per therm to 31.40 p/therm by 0759 GMT, with gas for Monday trading 1.1 p lower at 30.50 p/therm, reflecting a warming weather trend into next week.

Average temperature forecasts for Britain on Friday were 5.7 degrees Celsius, compared with Thursday's 4.6 degrees C, according to Thomson Reuters (Dusseldorf: TOC.DU - news) meteorologists.

Britain's Met Office also said temperatures from Sunday to Tuesday would be "steadily less cold".

Spot prices have fallen for the third session in a row after surging to their highest in nearly four months at 35 p/therm on Tuesday.

The gas system was broadly balanced, with demand expected at 274 million cubic metres (mcm) per day, 38 percent above the seasonal norm, and supplies seen at 262.9 mcm/day, National Grid (LSE: NG.L - news) data showed.

Norwegian gas flows to Britain via the Langeled pipeline rose to 60 mcm/day after dipping sharply overnight, National Grid data showed.

Meanwhile, supply from Britain's liquefied natural gas (LNG) terminals began tapering off, with South Hook pumping around 35 mcm/day. One new Qatari tanker, the Al Samriya, is confirmed to arrive on May 6.

The vessel took a roundabout route for Britain, sailing around Africa after departing Qatar, instead of taking the frequently used short-cut through the Suez Canal, shipping data shows.

In contrast to weakening spot prices, British forward contracts gained ground. The Winter 2016 gas contract rose by 0.40 p/therm to 35.80 p/therm as Brent crude oil futures hit fresh highs.

The Dutch day-ahead gas price at the TTF hub rose by 0.02 euro per megawatt hour (MWh) to 13.10 euros/MWh.

In the European carbon market, front-year EU allowances rose by 0.11 euros to 6.45 euros a tonne.

(Reporting by Oleg Vukmanovic in Milan; Editing by Nina Chestney)