In article ,
Hugh Newbury writes:
Is there an archive of rainfall in the UK that I can check this
extraordinary claim?

Apparently Martinstown in Dorset 'holds the record for the most rain to
fall in a day since records began in the UK -- 11 inches'. No date
given, and the amount looks rather too vaguely accurate, if you see
what I mean.

Amy advice as to where to look on the internet most gratefully
received.

I don't know about on the Net, but I think the 11 inches is generally
accepted as being authentic. Various books quote it, including Philip
Eden's "Weatherwise", which gives quite a lot of detail, even including
the name of the observer. The date was 18th July, 1955.
--
John Hall
"It is a very sad thing that nowadays there is so little useless
information."
Oscar Wilde (1854-1900)