UK GAS-Prices rise as imports from Norway dip

LONDON, Aug 13 (Reuters) - British wholesale gas prices rose on Tuesday morning as imports from Norway fell, creating undersupply.

* Within-day gas price up 1.30 pence at 31.20 pence per therm by 0809 GMT.

* Day-ahead gas price up 0.90 p at 30.50 p/therm.

* "Prompt prices are all up a bit on lower supply," a gas trader said.

* UK gas system undersupplied by 11.7 million cubic meters (mcm) with demand forecast at 153.3 mcm and flows at 141.6 mcm/day, National Grid data showed.

* Imports from Norway through the Langeled pipeline were 32 mcm, around 9 mcm lower than the previous day.

* Traders said expectations of low output from the country's wind farms had also boosted within-day gas demand from power stations.

* Peak wind power generation is forecast at 3.5 gigawatts (GW) on Tuesday, rising to 5.7 GW on Wednesday, National Grid data showed.

* "We expect low wind power generation today; adjusting higher from tomorrow with wind speeds climbing later in the week and during the weekend," analysts at Refinitiv said in a daily research note.

* Further out on the curve prices were mixed.

* September contract down 0.60 p at 33.00 p/therm.

* Winter 2019 contract up 0.25 at 49.75 p/therm

* Day-ahead gas price at the Dutch TTF hub up 0.22 euro at 10.65 euros per megawatt hour.

* Benchmark Dec-19 EU carbon contract up 0.15 euro at 26.85 euros per tonne. (Reporting by Susanna Twidale; editing by Nina Chestney)