Surely the latter part, rain being evenly distributed throughout the
year, has traditionally been fairly true, at least in eastern areas,

But not in many western areas

E.g.
Penzance 1971-2000

Nov 139.8
Dec 149.2
Jan 141.3
TOTAL 430.3

May 64.5
June 67.9
July 55.4
TOTAL 187.8 - Just 43% of the Nov-Jan total

Graham
Penzance