"Tudor Hughes" wrote in message
...
A marked thunderstorm starting 1332Z with many c-g discharges, one or two
quite close (about half a mile). More interestingly, the precipitation was
mostly large snow pellets, up to 20 mm, quite lumpy and hard but certainly
not hail. Outside it was like being pelted with white fudge. The total
amount was not large but enough to almost completely whiten the short grass
in my back garden. The temperature fell from 9°C to 6°C. The sky was
yellowish (and still is) with haze and had a distinctly summery look but
other factors soon gave the lie to that.
A combination of late March sunshine a cold pool (524 dam) must be what
set it off. I notice that showers broke out widely over southern England
and the Midlands from from about 10 a.m. onwards.
Do I call this snow? If so, that is 2 consecutive days in March with
snow but none in "winter".

Tudor Hughes, Warlingham, NE Surrey, 556 ft.



You raise an interesting point, Tudor. I have always been of two minds when
logging snow pellets. Officially, snow pellets come under the category of
'ice meteors', and are logged as such with small hail (ice pellets), snow
grains and diamond dust, hail itself being reserved for hail stones of 5mm
dia or more.

I made a note in my Observer's Handbook back in the 1970s against the
definition of snow pellets; 'snow or hail depending on size', and later in
the early 1980s; 'classed as hail provided that the hail pad is marked,
otherwise snow'. These definitions are not, I think, official, but just for
my own benefit, so that I do not have to agonise over how to classify them
on the rare occasions that they occur.

We recently had a fall of snow pellets on the 23rd, and these were up to
appx. 6 mm dia. At the time I thought I would call them snow, especially as
they produced a temporary covering on the roads etc. But when I returned
home, I found they had marked the hail pad well, thus changed my mind to
enter them under the 'small hail/ice' category.


--
Bernard Burton

Wokingham Berkshire.

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