On Sun, 16 Mar 2014 10:46:00 +0000, Vidcapper
wrote:
If so, I never realised there could be *that* much variability in a
supposedly stable airmass?

It's quite common - I've seen similar each of the 7 years I've had my
VP.

--
Freddie
Castle Pulverbatch
Shropshire
221m AMSL
http://www.hosiene.co.uk/weather/
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