Unusual diurnal cloud variation
Nick wrote:
The weather since about Friday seems to have followed the same diurnal
pattern (south Hampshire). Despite being a "polar maritime" airstream,
normally characterised by clear nights and early mornings (till about
10am) with cloud most extensive from about 10am until maybe an hour
before sunset, instead, the mornings have been universally cloudy (8am
and 9am being pretty much overcast on each day) while the late
afternoon and early evening (starting about 3pm, particularly after
5pm) have been sunny (every day except Sunday predominantly sunny or
clear between 7-9pm). However after dark cloud increases again, with
at least partial cloud cover before midnight. A couple of days have to
be discounted due to fronts/troughs complicating things, but other
than that it seems more like a typical "stratus burning off" setup
(typically found in either NE or tropical maritime airmasses) -
despite the cloud being cumulus.
Nick
I'm guessing it's been more of an rPM for most of the time with the air
taking a long sea track over anomalously warm waters to the WSW of us and
so picking up a lot of moisture.
I wish I'd still got a view of a trajectory program to see the source and
track of the air reaching us over recent days, but that's one of the
downsides of retirement.
--
Graham P Davis, Bracknell, Berks., UK. E-mail: newsman not newsboy
"I wear the cheese. It does not wear me."
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