2007- part 1: March 18th - Convective storm spectacular!
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It's been a while again since I
updated the site! Too much work and not enough storms!
March is typically an awkward month for
storm-photography. Sea temperatures are pretty much at
their coolest, so that it takes very cold air to move in
over the sea for convection to fire: the other side of
the coin is that inland, solar heating starts to have an
effect, so that "home-grown" storm-cells,
albeit fairly weak, are able to develop. Two dates did
provide something worthy of attention: firstly an
afternoon during which distant fallstreaks provided a
couple of tidy shots from Borth....
....and, more significantly:
Sunday March 18th did break
with the trend, and gave an excellent potential
opportunity for the camera. Here's a snippet of
forecast discussion from the UK Weatherworld
forum (highly recommended to anyone with more
than a passing interest in all things weather):
"Synopses show a number
of very active surface troughs moving in across
Ireland and the UK throughout the day. Upper cold
pooling is synonymous with expected lapse rates
near coastal regions likely to soar! In fact this
gives for a VERY unstable atmosphere which will
likely show numerous convective thundersnow
showers to most coastal regions for UK and Eire
through Sun and Mon. Prime convection will
utilise milder sea temps and thus favour west
facing coastal regions through the said period."
Although there were the usual waverings in the
model output, the day still looked good, so it
was definitely a case of heading to the coast in
the chilly winds and sitting it out to see what
would turn up. Tywyn was first port of call,
followed by the high coastal vantage point near
Llwyngwiril. I think the results justified the
Upon arrival at the coastal vantage-point, and in
the first showers trundled - tight little cores
of small hail and a bit of sleety snow - nothing
very exciting as yet...
Because they were dropping hail/snow, they looked
heavier than they actually were! Periodically,
bright sunlight dappled the water, which was
fairly murky following the strong winds that tend
to stir up sediment on the sea-bed...
The first bunch of showers decayed as they
approached leaving swirls of remnant
precipitation, but with more visible beyond -
perhaps the next lot would deliver the goods?
As luck would have it, an intense cell could now
be seen upwind (out of view R), clipping the
Lleyn Peninsula, whist dark scud bowled along
overhead in the NW-erly near-gale. I decided to
await its arrival, figuring its SW edge would
just about clip me so that I would get a
reasonable view of any interesting developments
right up to the last minute....
...as it moved closer a gust-front started to
develop around its forward flanks, whilst beyond,
the darkness suggested heavy snow and hail was
falling (as indeed had been forecast). The
lighting was good as the late afternoon low-angle
sunlight was filtering in from the L....
...providing a stark contrast between the
gust-front and the darkness beyond...
...very close now, with sunlight partly
illuminating the sea, and hail could be seen
falling only a sort distance to my north. I made
a pass northwards under the gust-front, complete
with a "whale's mouth" structure which
I didn't bother with as the view also included
rooftops and overhead lines!
In Llwyngwiril, hail fell in torrents, rattling
on the jeep roof and spinning along the street in
squalls, and I turned around to get back to the
...to find myself beneath this incredible, very
low and extensive anvil. Convective storms in
winter often exhibit very low anvils and are
often referred to as "low-topped"
storms. Another core of precip was visible out to
sea, but the main storm was passing, and sunset
was slowly approaching....
Shortly, the remains of the clump of storm-cells
was to pass away over the hills inland, with the
setting sun providing some nice optical
...before dipping below the visible horizon,
leaving raggedy cumulonimbus clouds to form a
Further showers fell as snow overnight, but
amounts were largely small. As high pressure grew
over the UK into April, with attendant climbing
temperatures, the camera stayed in the bag
...as the haze prevented a decent look at most
things. I liked this view, with the outlines in
differing greys, from the New Precipice Walk near
Dolgellau, looking SW towards the foothills of
Cadair Idris, with the mountain itself in the
background. On some days the haze has left
visibility down to only a mile or two. Occasional
slack low-pressure incursions have created small
amounts of instability inland and I did manage to
chase what turned into one of two thunderstorms
over Wales a few days ago, but in terms of rain
that has pretty much been that!
Luckily the ground-moisture has balanced out the
lack of rain up until now (April 20th) to a great
extent, allowing an excellent display of spring
hedgrow flowers - not something I am much good at
photographing but I couldn't resist a shot of
these wood anenomes about a week ago!
Will May bring anything different, or will dry,
sunny and unexciting for the forseeable future?
Time will tell!
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