UK GAS-Prompt prices rise as demand grows and supply falls

* Day-ahead price up 0.3 pence/therm at 39.50 p/therm

* Heating demand rises, flows from Norway down

Oct (HKSE: 3366-OL.HK - news) 6 (Reuters) - British gas prices rose on Tuesday after a drop in flows from Norway left the system under supplied at a time of rising demand for the fuel.

Gas for instant delivery rose 0.10 pence per therm at 39.50 per therm by 0725 GMT, while prices for Wednesday rose 0.30 pence to 39.50 p/therm.

With daily demand pegged at 220 million cubic metres (mcm) per day, Britain's gas market was under supplied by 11.6 mcm, according to National Grid (LSE: NG.L - news) data.

Local (Other OTC: LOCMQ - news) distribution zone gas heating demand is forecast to be 13 mcm higher day on day at 93 mcm, analysts at Thomson Reuters (Dusseldorf: TOC.DU - news) Point Carbon said.

Gas deliveries from Norway via the Langeled pipeline, the UK's main import artery, fell overnight to around 50 mcm/d from around 60 mcm on Monday, National Grid data showed.

Throughput from Total (Swiss: FP.SW - news) 's St. Fergus terminal also declined to around 14 mcm compared with Monday's levels of 16 mcm.

Temperatures in Britain are seen falling towards the end of this week to below normal levels, with night temperatures in London dropping to 9-10 degrees from 16 degrees on Monday, the UK's Met Office said.

Britain exported less gas to Belgium at 11 mcm/day due to UK prices rising on European hubs, reducing incentives to sell gas on the continent.

On the supply side, Centrica (LSE: CNA.L - news) said a maintenance outage at its North Morecambe gas terminal would end on Oct. 9, while Shell (LSE: RDSB.L - news) said it had ended its planned outage at St. Fergus.

Supply from the South Hook LNG import terminal, however, dropped to 35 mcm/day, from 42 mcm on Monday.

Gas prices further out on the curve fell.

Summer gas prices fell 0.10 pence to 38.30 p/therm.

In the Netherlands, the day-ahead gas price at the TTF hub was unchanged at 17.75 euros per megawatt hour.

In Europe's carbon market, the benchmark EU Allowance (EUA) slid by 0.02 euros to 8.19 euros a tonne. (Reporting by Oleg Vukmanovic in Milan; editing by xx)