On Oct 26, 9:53 am, (Adrian D. Shaw) wrote:
Felly sgrifennodd Dave Ludlow :

The return period for
such an occurrence is, again, roughly once in 200 years."For any one given place (or specifically for this one location), or for
the whole of the UK? It makes a big difference! If for any one given
place, that's not so amazing.

Adrian
--
Adrian Shaw ais@
Adran Cyfrifiadureg, Prifysgol Cymru, aber.
Aberystwyth, Ceredigion, Cymru ac.http://users.aber.ac.uk/ais/weather/ uk

You seem to be confusing a large pressure change with a
localised phenomenon like heavy rainfall. A once-in-200 yr deluge at
any one place could be found *somewhere* in the country almost every
year but a large pressure change affects a much larger area than a
violent downpour. There was a rapid rise in pressure over thousands of
square miles and each station that recorded it would have its own "once
in 200 yr" record.

Tudor Hughes, Warlingham, Surrey.