UK GAS-LNG terminals and storage left to fill Norwegian supply gap

* UK Monday gas rises 1.2 pence at 42.90 p/therm

* Norwegian outages, diversions to Germany tighten supply

* LNG and possible storage withdrawals to fill gap

Sept 7 (Reuters) - British wholesale natural gas prices rose on Monday after sharp reductions in Norwegian supplies led to shortages, requiring large withdrawals from stored reserves to plug gaps.

Gas for instant delivery rose 1.20 pence to 42.90 p/therm by 0921 GMT, reflecting scarce supply, as day-ahead prices gained 0.65 pence to 42.40 p/therm, a Reuters composite of brokerage trade data showed.

Weekend gas prices rose over half a penny to 42 p/therm.

Britain's gas network was under supplied by 37.7 mcm/day, with demand pegged well above average levels at 191.2 mcm, National Grid (LSE: NG.L - news) data showed.

Norwegian imports dropped due to the start of maintenance at the Kollsnes gas processing platform, which cut output by 39 million cubic metres/day (mcm), and the re-opening of Germany's Emden receiving terminal, which attracted more Norwegian gas away from the UK.

An ongoing outage at Norway's Nyhamna, a gas processing plant, further reduced overall export capacity by 5 mcm.

Norwegian imports to Britain via the Langeled pipeline dropped to 20 mcm from 61 mcm on Friday, National Grid data showed.

"We expect Langeled flows to remain just slightly above 20 mcm/d until maintenance at Kollsnes ends on 19 September," analysts at Thomson Reuters Point Carbon said.

Storage sites are not currently forecast to withdraw any gas on Monday, raising questions over how supply gaps will be plugged.

Ongoing outages at Centrica (LSE: CNA.L - news) 's Morecambe gas fields in the Irish Sea and ConocoPhillips (NYSE: COP - news) ' fields feeding the Theddlethorpe terminal further restricted supply.

With few other options immediately available, analysts expect flows from the South Hook liquefied natural gas (LNG) terminal to rise above already high forecast rates of 40 mcm.

"Further strain on the system dynamics is coming in the way of forecast demand above seasonal normal level as (gas-fired power plant) demand has increased due to a fall in wind generation," said Marcel Boonaert, head of trading and portfolio at Wingas UK.

Bonnaert, however, expected a ramp-up in withdrawals from storage to help plug shortfalls.

Further along the curve, prices for winter delivery rose to 44.55 pence per therm, up 0.25 pence from the previous trading session.

In the Dutch TTF gas market, prices were also higher across the board. Day-ahead TTF gas gained 0.25 euros to 19.60 euros per megawatt hour.

In Europe's carbon market, benchmark EU Allowances (EUA) eased by 0.03 euros to 8.07 euros a tonne. (Reporting by Oleg Vukmanovic in Milan; Editing by Louise Heavens)