* Within-day gas was up 1.75 pence at 58.00 p/therm.

* Day-ahead gas was up 2.70 pence at 59.00 pence per therm at 0945 GMT

* Expected cold weather that arrived with a day's delay was behind the rise in prices, which fell sharply yesterday when the day proved to be warmer than forecasts had showed, a British gas trader said.

* "Yesterday after the weekend we saw a delay in the cold arrival and markets tanked... Today we see a confirmation of the cold, as expected by the market," he said.

* Average daily temperatures in Britain are expected to be 6.9 degrees Celsius on Tuesday and to fall to 3.7 C on Wednesday.

* The system was oversupplied with demand in Britain forecast at 286.3 million cubic metres (mcm) per day and flows at 296.5 mcm/day, National Grid data showed.

* Norwegian gas flows to Britain stood at 106 mcm/day from 111 mcm/day on Monday.

* Britain expects four liquefied natural gas tankers until the end of the week.

* Prices rose despite strong power output from wind turbines, which otherwise decreases demand for electricity generated in gas-fired power stations.

* On Tuesday peak wind generation was forecast at 11 gigawatts (GW) out of a total capacity of more than 12 GW. It is expected to fall however to 6.5 GW on Wednesday.

* February contract rose 2.05 pence to 61.00 p/therm.

* Day-ahead Dutch gas at the TTF hub rose by 0.98 euro to 21.63 euros per megawatt hour.

* The benchmark Dec-19 EU carbon contract rose by 0.57 euro to 22.82 euros per tonne.