LONDON, Nov 21 (Reuters) - British wholesale gas prices rose on Thursday morning as supplies from the country's liquefied natural gas (LNG) terminals fell, leaving the market undersupplied.
* The within-day contract was up 1.05 pence at 40.90 p/therm at 0934 GMT.
* The day-ahead contract was up 0.10 pence at 40.10 p/therm.
* Traders said send-out from many from some of the country’s LNG terminals was much lower on Thursday.
* Total LNG send-out was 69 mcm, down 24 mcm from the previous day, Eikon Refinitiv data showed.
* Four LNG tankers are scheduled to arrive in Britain by the end of the week, which will replenish supply.
* Britain's gas system was undersupplied by 34.5 million cubic metres (mcm), with demand forecast at 310.3 mcm and flows at 275.8 mcm/day, National Grid data showed.
* Output from the country's wind farms is also expected to drop on Friday, boosting demand for gas from power stations.
* Peak wind output is expected at around 10 gigawatts (GW) on Thursday, falling to 7.4 GW on Friday, Elexon data showed.
* Further out on the curve, most contracts also edged higher.
* The December gas contract was up 0.41 p at 40.88 p/therm.
* The summer 2020 contract was up 0.35 p at 38.60 p/therm
* Day-ahead gas price at the Dutch TTF hub up 0.17 euro at 15.35 euros per megawatt hour.
* Benchmark Dec-19 EU carbon contract up 0.07 euro at 24.10 euros per tonne. (Reporting By Susanna Twidale; editing by Nina Chestney)