The depression which brought severe weather to north-west Europe
during 25 and 26 January began on the 23rd as an innocuous-looking
wave on a cold front in the North Atlantic about 400 miles south-east
of Nova Scotia.
By midday on the 24th the central pressure of the low had dropped
to 992 mb, and conditions were favourable for it to deepen explosively.
The storm arrives
As the low approached Ireland during the early hours of a the
25th the most rapid strengthening phase of the storm was taking
place with the central pressure now down to 968 mb and the whole
system showing a 'hook' shape in satellite imagery - this shape
normally indicating the development of a severe storm. The storm
centre tracked across Northern Ireland on the morning of the 25th
(with falls in pressure in the order of 16 mb in three hours)
and by midday was centred over Ayrshire. The lowest central pressure
of 949 mb was estimated at around 1600 to the east of Edinburgh
as the storm continued its rapid movement towards Denmark.
The strongest winds occurred on the western and south-western
flanks of the storm with average speeds of 40-50 knots over large
areas of England and Wales. In exposed areas on the south coast
of England and west Wales, the mean speeds reached 60-65 knots.
But it was the gusts that did most of the damage. The highest
gust was 93 knots (104 m.p.h., recorded at Aberporth) but several
gusts of 90 knots occurred over large areas of southern England.
Met Office warnings
The Met Office gave excellent warning of this storm. Forecasters
are expert at handling an ensemble of solutions from different
forecast centres and on this occasion the signal for marked strengthening
of the depression was clear.
Emphatic guidance of severe gales was issued in a routine TV
broadcast four days before the storm arrived, but with uncertainties
about the track. As the event drew closer, more precise forecasts
were issued on 24 January based on the forecast from the 'fine-mesh'
model then in use. A press release was issued about the possibility
of structural damage, and the Ministry of Defence was notified
that military assistance to the civilian population might be required
owing to the severity of the winds.
This storm produced winds of comparable strength to the storm
of 1987 but they covered a much wider area. Despite timely warnings
from the Met Office, the casualties were higher than in 1987 because
of the daytime arrival of the storm (compared with overnight in
1987) and the greater area affected.
Storm damage
In its wake the storm left a trail of death and destruction both
on land and at sea. It was reported that 97 people died in northern
Europe, with half this number being in the UK. Road, rail and
ferry services were disrupted and great damage was inflicted on
the countryside - an estimated three million trees were blown
down in the UK alone. Power lines were also brought down in this
country and parts of mainland Europe.
Parts of Hereford and Worcester were flooded when the River Severn
rose by 3.5 m, while in West Germany a coastal village was evacuated
when threatened by floods from a breached dyke. The port area
of Hamburg was also flooded.
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