This week's warm spell - I registered 22c again today - reminded me of a
similar spell in 1978 when I recorded max of 24c on both the 11th and 12th.
In that year the weather turned foggy for the next 2 days although the
afternoons were sunny but the max was down to 16c on the14th. In 1978, the
November which followed was exceptionally mild until the 24th and it looked
as the the month was heading to be the warmest on record, but then a cold
northerly set in and there were sharp frosts in the final week.
Going back a bit further, I see from my weather diary for 1949 that I
recorded lunch - time readings above 21c almost every day until the 15th on
a thermometer fixed to the north wall of the house. That year , autumn
arrived on the 26th; I had a temperature of 20c on the 25th, at breakfast
time on the 26th it was 14.5c, the cold front went through in the morning
with heavy rain, and by lunchtime the thermometer reading was 9c. The first
air frost of the season followed 2 days later.

Peter Clarke
Ewell, Epsom 55m