I've recently been looking at statistics for Exeter, going back to
1973, and discovered that the lowest temperature in the period 1973 to
2007 occured on 2nd January 1979 with Minus 13c.

http://www.tutiempo.net/clima/Exeter...1979/38390.htm

Also, I have produced a rolling annual average temperature based on
daily temperatures. Interesting to note that the coldest year was the
12 months to 27th January 1997.

http://s2.excoboard.com/forums/16030...331/373640.jpg

I will produce more stats / trends for Exeter over the coming weeks,
when I have a little more time.