LONDON, May 11 (Reuters) - British wholesale gas prices were lower on Monday morning as gas was re-routed from continental Europe to Britain, creating oversupply.
* The day-ahead contract fell by 0.85 pence to 13.50 pence per therm by 0826 GMT.
* The June contract was 0.25 pence lower at 13.50 p/therm.
* Demand is forecast at around 210 million cubic metres (mcm) and flows at 237 mcm/day, leaving the system oversupplied by around 27 mcm, National Grid data shows.
* The oversupply is due to gas being re-routed to the Langeled pipeline to Britain from the Franpipe pipeline which transports gas to France from Norway.
* Franpipe flows are at zero, with maintenance reported by GRT Gaz until 16 May.
* Langeled flows are nominated at 52 mcm/d compared to 27 mcm/d the previous working day.
* Liquefied natural gas send-out is also likely to increase in the coming days and over the weekend to accommodate scheduled cargoes, Refinitiv gas analysts said.
* Wind output is high on Monday, likely reducing demand from gas-for-power plants.
* Peak wind generation is forecast at 10.3 gigawatts (GW) on Monday, falling to 5.7 GW on Tuesday, Elexon data shows.
* In the Dutch gas market, the day-ahead gas price at the TTF hub was up by 0.35 euro at 5.55 euros per megawatt hour.
* The benchmark Dec-20 EU carbon contract was 0.31 euro lower at 19.04 euros a tonne. (Reporting by Nina Chestney)