UK spot gas extends weather-driven gains

* Demand 30 percent below historical average

* Storage facilities emptier compared with last year

LONDON, June 7 (Reuters) - British prompt gas prices rose on Thursday morning, due to an undersupplied network as higher heating demand driven by unseasonably cold temperatures, elevated exports and storage refills tightened the fundamental outlook.

The day-ahead gas contract was little changed at 56 pence per therm amid expectations of more supply availability combined with lower demand prior to the weekend.

Gas for immediate delivery increased 0.70 pence to 56.70 pence. The country's pipeline network opened 17 million cubic meters/day short of gas, which narrowed to 11.5 mcm/day short by 0830 GMT.

While demand at 199 mcm/day was 30 percent below the historical average on Thursday, traders said the comparison was misleading as it contrasted current recession-constrained demand levels against economically prosperous periods.

"The prompt market found a bottom at 53 pence a therm...it has bounced off that to trade in the mid-50s range, now we're waiting to see if it can go any higher," a trader from a major European utility said.

SUPPLY AND DEMAND

Long-range gas stockpiles were 70 percent full, versus 33 percent full in 2011, while mid-range inventories were 30 percent full compared with 46 percent last year.

The benchmark winter 2012 gas contract was little changed at 65.9 pence.

UK Continental Shelf production was unchanged at 117 mcm/day, while Norway contributed about 40 mcm/day.

Planned exports to Europe steadied at 23 mcm/day and injections into storage were pegged at 20 mcm/day.

WEATHER

The UK MetOffice's 6-15 day weather forecast said: "Temperatures generally slightly below average, perhaps recovering to near average later."