Date: Wednesday 18th August 2004 Time: 19:03
Macclesfield, Cheshire UK
Returning Polar Maritime
Duration: 40 minutes
Average lightning type: C-C
Average discharge rate: 38 seconds
Footage Quality: VHS, DIGI
was quite a substantial upgrade on T0053 which passed just 2 hours before in
the same unstable returning polar maritime airmass, heated by the strong
I spotted the cells on the horizon with explosive towers.
it got closer a there was a defined linear arcus cloud all the way along the
west horizon. It was clear that this was more organised
than T0053 and probably associated
with a strong pool of cool sinking air, likely aligned with an embedded
upper trough, perhaps with more instability than T0053 being closer to the
upper low centre.
was a constant background rumble of thunder caused by weak discharges taking
place just behind the arcus cloud that were only visible as very faint flashes.
These may have been weak upper anvil flashes too.
I was expecting to see some C-Gs from under the linear arcus (common) but throughout
the entire storm I didn't witness a single strike of the like. This may be
due to the vertical wind shear setup, perhaps not enough to shear the
positive and negative regions away, but enough to allow enough
rearward-slope to encourage C-Cs behind the arcus.
got closer the arcus cloud demonstrated classic “Whales Mouth” formation dominating the skies and looked
hidden low-amp lightning was eventually revealed as the arcus went overhead,
delivering a large smooth downdraught base in which
large C-Cs started to spark in every direction, some with return strokes and
leaders. The C-Cs were still of low-amp nature but they looked good and were
bright compared to T0053.
This was one of the most fully-documented storms I have filmed in terms of
approach, characteristics and departure. The anvils were clearly visible on
approach, then the arcus, followed by whales mouth, then lightning display
and departure in the sunset.
All that was missing was a rainbow.
EUROPE 24-hour SFERIC LOCATION
EUROPE 24-hour SFERIC INTENSITY
SATELLITE IMAGES (Credits)
VISIBLE 18.08.2004 15:44
VISIBLE 18.08.2004 15:44 + Grid
INFRARED 18.08.2004 15:44
INFRARED 18.08.2004 15:44 + Grid
COLOUR 18.08.2004 15:44
COLOUR 18.08.2004 15:44 + Grid
T0053 was embedded in the arc of
convection seen across the Midlands, whilst T0054 is shown brewing in a new
line of convection positioned western Wales.