* Within-day gas price rose 0.75 pence to 38.75 p/therm by 0850 GMT.

* Day-ahead price had yet to trade but closed at 38.00 pence p/therm.

* The system opened almost 20 mcm undersupplied with demand forecast at 262.2  million cubic metres (mcm) and supply seen at 242.4 mcm, National Grid data showed.

* An unplanned outage at Norwegian gas fields has led to flows being reduced to the SEGAL pipeline system.

* GASSCO said the impact of the outage on Tuesday would be 3 mcm, although nominations are down 5 mcm.

* Additionally, strike action on Tuesday by Total  workers may reduce flows from British gas fields.

* Send-out rates from LNG terminals were high at 52 mcm, with three tankers docking or discharging in the past 24 hours and another three due to come before the end of the week.

* LNG imports in March stand at 1.18 million tonnes, the highest level since October 2015.

* On the demand side, temperature forecasts were increased for today and tomorrow, with accompanying reduction in gas demand forecasts.

* Residential gas demand was seen to be about 20 mcm lower for Tuesday at 159 mcm and for Wednesday at 142 mcm.

* "Temperatures are expected to increase sharply tomorrow and the week ahead will bring significantly soft consumption, continuing well below seasonal normal within our 14-day forecast horizon," gas analysts at Refinitiv said.

* The April contract rose 0.4 p to 38.20 p/therm.

* The Summer 2019 contract was up 0.15 p at 38.70 p/therm.

* The British day-ahead gas contract dipped below day-ahead Dutch gas prices on Monday, ruling our pipeline imports from the Netherlands and Belgium via the BBL and IUK pipelines.

* Day-ahead gas price at the Dutch TTF hub was yet to trade on Tuesday but closed at 15.40 euros per megawatt hour.

* The benchmark Dec-19 EU carbon contract was down 0.31 euro at 21.51 euros per tonne.