UK GAS-Prices decline on mild weather forecasts, LNG deliveries

April 17 (Reuters) - British gas prices fell on Friday on healthy supplies and milder weather forecasts for next week combined with expected liquefied natural gas (LNG) shipments into north-west Europe.

Prices for delivery on Monday fell 1.5 pence per therm or 3.16 percent to 46 pence at 0853 GMT, while prices for within-day delivery were down 2 percent at 45.80 pence.

With supply flows forecast to be around 201.1 million cubic metres (mcm) and expected demand around 203.9 mcm, the system was nearly 3 mcm undersupplied on Friday, National Grid (LSE: NG.L - news) data showed.

"The system is fairly well supplied and demand has been reduced compared with yesterday," one European utility trader said.

Next week is forecast to see milder temperatures, which could also be pulling prices lower, an analyst said.

Forecasts predicting temperatures above the seasonal norm next week may also be weighing on prompt prices, an analyst said.

The South Hook LNG terminal was pumping out just under 30 mcm/day after reaching highs of 34.5 mcm on Friday morning, above levels in the previous session, which added to supply.

Britain was due to receive another Qatari LNG cargo aboard the Al Ghariya on Friday, followed by the Al Samriya on Sunday.

In Belgium, four tankers were expected to arrive between April 20 and May 1, shipping data showed.

Britain's Rough natural gas storage facility will have its withdrawal capacity reduced by six mcm per day between 1000 and 1600 local time on Friday, operator Centrica (LSE: CNA.L - news) said.

Shell (LSE: RDSB.L - news) did not respond to queries about sharply reduced gas flows into its Bacton terminal in the UK.

Flows into the terminal fell to around 4 mcm from 10 mcm earlier in the session. Gas deliveries from Norway, Britain's biggest supplier, fell to 59 mcm from 62 mcm on Thursday, data showed.

Gas for delivery in winter 15 was trading at 50.25 pence per therm, 0.53 pence down from the previous day.

In the Netherlands, the day-ahead gas price at the TTF hub was 0.37 euros lower at 21.80 euros per megawatt-hour (MWh).

The benchmark European Union carbon price dipped 3 euro cents to 6.88 euros a tonne on ICE Futures Europe. (Reporting by Oleg Vukmanovic; editing by Jason Neely)