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So
far it's been a winter like we've grown accustomed to over the last
few years - mild and with very few frosts, and little snow fall
to speak of.
The
three spells of 'wintry' weather, notably in November, Christmas
day, and again for a time in January lasted no more the 48 hours,
quickly replaced by milder Atlantic air. Indeed, it is the west
or southwest winds blowing in from the Atlantic which have kept
us so mild.
In
fact it's been so mild that I received a picture from a Look North
viewer in Lincolnshire in December showing his first daffodil! Since
then I have had numerous picture, with daffodils in bloom across
quite a few places by the end of January.
But
it's also been a stormy spell of weather. During the early hours
of Saturday January 8th a vicious area of low pressure tracked across
the Borders, leading to gusts of wind of 85mph at Leeming, North
Yorkshire.
Much
of Yorkshire and Lincolnshire were battered by these winds, with
structural damage and uprooted tress quite widespread. A second
vigorous depression followed on the following Tuesday night - this
brought heavy rain and severe gales again - but also a tidal surge
down the East Coast.
The
waves generated by the storm coincided with a high spring tide and
an uplift of the sea due to the very low pressure of the storm system
- 940mb - which lead to coastal flooding.
A third
night of severe gales followed the next week, with gusts in Sheffield
of 76mph, and 85mph at Pateley Bridge, causing more structural damage.
Interestingly
as we end January, New England and the near continent are experiencing
real winter, with heavy snow and bitterly cold air.
These
two weather events are in fact linked by the upper air planetary
wave, otherwise known as the Rossby wave. Effectively the upper
air is behaving like someone is shaking a skipping rope. The Rossby
wavelength is such that the cold trough of air over New England
is followed by a warm ridge of air over the Atlantic, which in turn
is followed by a cold trough of air over Europe.
Sometimes
the wavelength is such that the cold trough falls over us; hence
we hear people say that if it snows in New York, we will get it
seven days later - this is not quite the old wives' tale people
make out!
As
we end January we are only just in the milder ridge - but interestingly
the long range predictors for February are beginning to suggest
that we may see some of the cold European air migrating westwards
towards us.
Winter
may not be done with yet!
Paul
Hudson
Feel
free to contact Paul by e-mail: look.north@bbc.co.uk.
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