UK GAS-Day-ahead price up on lower supply

LONDON, June 20 (Reuters) - British wholesale day-ahead gas prices rose on Wednesday after posting losses in the previous session as an ongoing outage in Norway restricted supplies and as flows into Shell (LSE: RDSB.L - news) 's St Fergus terminal fell.

* Day-ahead gas was up 0.25 pence at 53.80p/therm by 0832 GMT.

* The gas market was oversupplied despite reduced flows from Norway and into domestic terminals due to maintenance on a major export pipeline from Britain to Belgium, trapping excess gas in the UK.

* The gas system was oversupplied by 4.2 million cubic metres (mcm) a day, with demand forecast at 134.6 mcm/day and flows at 138.8 mcm/day, National Grid (LSE: NG.L - news) data showed.

* Analysts said the IUK shutdown meant some excess gas was being injected into Britain's gas storage sites but the extent of injections will hinge on deliveries into the system.

* Gas deliveries into Shell's St Fergus terminal fell to about 13 mcm/day earlier from 22 mcm/day overnight, but flows have recovered since to 20 mcm/day.

* The FLAGS pipeline feeds St Fergus with gas from Norway.

* Deliveries from Norway via the Langeled pipeline are already under pressure due to maintenance at the Kollsnes gas processing plant.

* UK Continental Shelf output was eight mcm/day lower at 111 mcm/day.

* "The Kollsnes outage is an ongoing bullish risk, especially if it is extended into the weekend," Thomson Reuters (Dusseldorf: TOC.DU - news) analyst Oliver Sanderson said.

* Further out on the curve prices also rose.

* The July contract was up 0.60 p at 53.95 p/therm.

* The day-ahead gas price at the Dutch TTF hub was unchanged at 22.10 euros per megawatt-hour.

* The benchmark Dec (Shanghai: 600875.SS - news) -18 EU carbon contract was up 0.07 euro at 14.31 euros per tonne. (Reporting by Oleg Vukmanovic, editing by Jan Harvey)