With a 70mm/hr+ core it
was quite a monster. I was in the Tywyn area and heading south through
murk and rain (blue on the radar plot) at the time and it was only when
I got to Aberdyfi at about 11.00 that I could see much. The tail-end of
the stormcloud was visible and had that hard, dark appearance typical
of a strong updraught-base, i.e. interesting - so I pulled into
the car-park alongside the beach at Aberdyfi and got the binoculars on
In no time at all I espied a thin funnel-cloud descending from the
cloudbase through the drizzle....
These are through a 300mm telephoto hand-held in a gale!
The funnel then seemed to give up the ghost, but I was still interested
in this area of the cloud, and swung the jeep round into a position
where I could wedge myself against the door-pillar with the 300mm lens
but also get some shelter from the rain.....
Pretty much as the
naked eye would see it. The lowered area may well be a shallow
wall-cloud - an area of low-level rotation within the stormcloud, and
where further funnel development would be possible - and that's exactly
what happened next!!
This time the funnel grew very rapidly and headed towards ground....
I guessed it was out over the sea, so would be reported as a
waterspout. My vantage point meant that the dunes at Ynyslas blocked
the view of its very base, but there was no hope of getting anywhere
better - the Dyfi Estuary was in the way for starters!
Really quite powerful in appearance now....
I think I can see spray
in this image being drawn into the vortex, giving it a paler colour....
Here, it is getting
thinner from above - a sure sign of weakening....
...and here a sheath of
spray mostly conceals the narrow central vortex as it starts to retreat
This is the "rope-out" stage, and within
seconds it had disintegrated and was no more.
My guess was that it was somewhere near Aberystwyth and after emailing
a BBC Wales contact this was confirmed - numerous excellent photos were
taken as it churned along off Aberystwyth Harbour. Reports that it
followed a heavy hailstorm with thunder and lightning are consistent
with the visual observations and the radar which showed that heavy
shower moving inland from Aberystwyth at the time, weakening as it went
(remember that in Winter, warm sea surface temperatures often drive
convection, which weakens when a convective storm leaves the sea
environment for the land environment)....
Another nice early-season catch then! The
rest of February has seen little serious convective activity and the
same goes for March - traditionally a quiet month for convective
storms, albeit often delivering some strong gales, about which more to
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