Only two days of gas are left in reserves because of extreme demand resulting from the coldest March in 50 years. Plunging temperatures have pushed up demand by 20 percent - causing supplies at storage facilities to drop to levels nearly 40 percent lower than last year.
The problem could worsen because natural gas supplies are being diverted to the Far East, where suppliers can get a higher price from customers, said energy analysts.
Rocketing energy bills could follow as hard-pressed households try to keep warm.
Utilyx consultant Andrew Horstead warned that customers would foot the bill for buying in emergency gas supplies.
"These are very high costs which will be difficult to be absorbed by supply companies. I would struggle to see these not being fed through to users some time in the future."
In parts of the country there is a 90 percent chance of heavy snow and ice over the weekend. A foot of snow could fall in some areas, said meteorologists, and there is also the danger of flooding and travel chaos.
Britain is in a worse position than other countries in Europe because there is only capacity for storing 15 days' worth of gas. In Germany and France, that figure is 100 days.
The Met Office has issued severe weather warnings for the East Midlands, Northwest England, Northern Ireland, Southwest Scotland, Lothian Borders, Southwest England, Wales and the West Midlands.
Britain's power infrastructure is creaking under the pressure of meeting existing demand, warned an energy expert.
Jeremy Nicholson, of the Energy Intensive Users Group, said: "It's going to be tight for the next couple of weeks. We would all feel more comfortable if the UK had more flexible storage."
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