"Martin Rowley" wrote...
snip
... caught me out too. Because of the 'anvil' reference, I thought
vaguely
about thunderstorms, but couldn't place the exact definition (before
the
answer was given!)

Mind you, there are a lot of terms that the severe convective
community use
in the US that aren't well know over here.

as here ....

http://www.srh.noaa.gov/oun/severewx/glossary.php

"Anvil zits", "Knuckles"!

Quite a few here I wouldn't recognise.


--
Martin Rowley
West Moors, East Dorset (UK): 17m (56ft) amsl
Lat: 50.82N Long: 01.88W
NGR: SU 082 023