UK moths

[Jacques Francis]

Driving along quiet single-track country roads in wooded Surrey tonight
(13-Dec-99), with the car's thermometer showing 0 to -2 and after a day of
dank grey overcast with long periods of rain (yes, I'd rather be in
Barbados), I caught at least 30 moths in the headlights. They all looked
about the same in size and colour - buff, and were quickly flapping their
wings. As I don't know a great deal about moths, I was surprised to see any
at all at these low temperatures.

Does anybody know if this is normal and I've been rather unobservant in the
past, or whether it's unusual. What sends moths to bed for the winter, and
are there some that come out irrespective of the weather?

Jacques Francis