In 1981 it got as low as -20C in Warwickshire, IIRC. Do you remember the lorry drivers use to light fires beneath their fuel tanks to get the diesel flowing? I was snowed in, in a little village called Ladbroke, and wrote an essay about Kant's Critique of Pure reason.
Ah I found a little report on that December.
In the brief interlude between the snowstorms of the 11th and 13th much of England was gripped by a frost of unprecedented intensity. At RAF Shawbury in Shropshire the temperature sank to minus 22.6C at daybreak on the 12th, climbed only to minus 12.1C that afternoon, then plummeted to minus 25.2C during the early hours of the 13th.
I lived in a cottage that was heated by kerosene, and it - well, the fuel didn't literally freeze solid, but it got too thick and viscous to flow through the pipe, so the cottage froze solid. I had one little electric radiator so I warmed one room, and me and my cat lived in there for a week. I would put on fur coat and boots and go and heat up a pan of water on the oven (luckily it was electric) and throw hot water down the toilet so I could quickly use it before it froze up again.
I know people abroad think the English are silly about weather, but it's the unpredictability of it which makes it hard to prepare for. It is probably more efficient to botch it yearly according to circumstances.
ETA I am wearing my Ace Rimmer sheepskin, well not this second, but when I go out.