As well as congratulating Andrew on his forecast, I'd like to comment
on some of the meteorological points raised. I use the original
Metcheck posting rather than the various media versions.

Andrew, you mention well defined Polar Cells which intrude into
Northern latitudes and also an increased frequency of Northerly winds
and North-easterly outbreaks.

As your statement showed a definite trend, I thought I'd check on that
to find out if I'd say the same. I used a 1/30 chart, meaning one
chart covering 30 days, and checked each month. . You say yourself that
the cold spells are short - rather than lasting a long period In
that case they would hardly show up on a 1/30 chart. I would, however,
see a tendency for your Polar Cells lying to the north of Scotland.

I Checked the area, North Pole down to Scotland using a 1/30 chart for
November 2004. At 60N to 65N, there was LP on the Iceland side and the
Scottish side. The HP was over Scandinavia and the continent. That
means S or SE winds would generally be expected over the British
Isles, especially over the E side of the country.

I did the same check for December. Once again LP was on the Iceland
side and HP was on the Scandinavian side. Southerly winds generally
up the E side of the country.

For January, LP on the Iceland side and a large amount of HP over the
continent stretching to Scandinavia. Winds interestingly, and
generally, SE into the SE of the country.

For February, the LP moved a little more towards Iceland so that the HP
over the continent and Scandinavia could cover part of SE Britain.
Winds generally light in the E and SE but generally S or SW in the west
of the country.

So for the monthly trend, the Polar Cells do not appear on the 1/30
charts. That doesn't mean your Polar Cells will not appear as you
say. It means to me, that your Polar Cells are very short lived in
the places you have stated. It also means that in the long trend,
the axis of HP is over Scandinavia or down from Greenland, but not
north of Scotland.

The signs of a very cold winter are usually a) continental HP
overhead, b) a strong easterly air stream coming off the continent, or
c) a wet snowy northerly airstream from the Arctic. As far as I can
see, the long term 1/30 charts suggest HP over Scandinavia and the near
continent is the best we can hope for. LP to our north and north-west
doesn't supporrt the cold weather you have described. . I could
imagine a condition in which the continental HP is much stronger than I
anticipate, and that would put your forecast in good stead. Perhaps
your method is better capable of anticipating a strengthening of the
continental HP than mine is.

I didn't do a check with the 1/10 charts (one chart covers 10 days)
because it's more work and I'm short of time. It is something I can do
at a later date if necessary.

You mentioned 3 cold periods which are well worth looking at.
22nd to 27th November: I noticed HP over the continent and a large LP
to the west of Britain moving to cross the top of Scotland before
reaching the Norwegian coast. on 25th. There is a secondary with the
LP which comes into the Channel on 24th. Now this; I think, is the
coldest day of this period, because there's a chance of continental air
coming into SE England as an easterly wind round the secondary. On 25th,
HP to the west of Ireland moves eastwards bringing cold and wet
north-westerly winds into the country for the 26th. Then we have night
frost with the HP over England for 27th. So apart from the
continental inflow on 24th I can't see the bitter chill of a special
cold winter during this period.

4th to 11th December: On 4th, I noticed a bridge of HP running W/E
across the middle of the British Isles with easterly winds running
into the southern counties. After that, HP to the west of Ireland
crosses the country on 5th and 6th. And after that a litter of
depressions cross Scotland - and to the north of Scotland - during
7th to 10th, leaving Britain on 11th with pressure rising over the
country. Apart from 4th December, there is nothing out of the ordinary,
in my view, for calling this a cold period.

22nd to 25th January: On 22nd I have a complex depression coming into
western areas. There is some HP near the SE of England as a left-over
from the continent. There is a chance that the SE winds could bring
cold air in from the continent at first, but not for long. The whole LP
system moves across Scotland on 24th. A secondary LP comes into S
Ireland on 23rd and moves into the Channel on 25th with pressure
rising over the central British Isles. So apart from SE to SW winds
during most of the period I could perhaps see easterly or south-easterly
winds being possible on the 22nd, the first day and the 25th, the last
day of the period.

The 1/30 charts suggest that a few cold days could start in January,
but the main thrust looks to me like being in February, then tailing
off for March. It's not a continual cold period but a larger frequency
of short-period-chills from the continent. The LP to the NW of Scotland
is a determining factor for warmer conditions from the SW, and from
March to April this LP system appears to gain more influence over our
weather.

If your forecasting system is capable of taking into account an
above-normal intensification of the European HP - which my system is
not - then your forecast may have some chance of being partly
correct.

Cheers, Keith

Keith, to be honest I've followed your forecasts right through the last year
and at best I can say 50% of the time you are correct, which unfortunately
leaves the other 50%. I suspect most members of this NG would achieve
similar accuracy with experience/guesswork.


Regards


Sean Blowman


"Keith Darlington" wrote in message
...
As well as congratulating Andrew on his forecast, I'd like to comment
on some of the meteorological points raised. I use the original
Metcheck posting rather than the various media versions.

Andrew, you mention well defined Polar Cells which intrude into
Northern latitudes and also an increased frequency of Northerly winds
and North-easterly outbreaks.

As your statement showed a definite trend, I thought I'd check on that
to find out if I'd say the same. I used a 1/30 chart, meaning one
chart covering 30 days, and checked each month. . You say yourself that
the cold spells are short - rather than lasting a long period In
that case they would hardly show up on a 1/30 chart. I would, however,
see a tendency for your Polar Cells lying to the north of Scotland.

I Checked the area, North Pole down to Scotland using a 1/30 chart for
November 2004. At 60N to 65N, there was LP on the Iceland side and the
Scottish side. The HP was over Scandinavia and the continent. That
means S or SE winds would generally be expected over the British
Isles, especially over the E side of the country.

I did the same check for December. Once again LP was on the Iceland
side and HP was on the Scandinavian side. Southerly winds generally
up the E side of the country.

For January, LP on the Iceland side and a large amount of HP over the
continent stretching to Scandinavia. Winds interestingly, and
generally, SE into the SE of the country.

For February, the LP moved a little more towards Iceland so that the HP
over the continent and Scandinavia could cover part of SE Britain.
Winds generally light in the E and SE but generally S or SW in the west
of the country.

So for the monthly trend, the Polar Cells do not appear on the 1/30
charts. That doesn't mean your Polar Cells will not appear as you
say. It means to me, that your Polar Cells are very short lived in
the places you have stated. It also means that in the long trend,
the axis of HP is over Scandinavia or down from Greenland, but not
north of Scotland.

The signs of a very cold winter are usually a) continental HP
overhead, b) a strong easterly air stream coming off the continent, or
c) a wet snowy northerly airstream from the Arctic. As far as I can
see, the long term 1/30 charts suggest HP over Scandinavia and the near
continent is the best we can hope for. LP to our north and north-west
doesn't supporrt the cold weather you have described. . I could
imagine a condition in which the continental HP is much stronger than I
anticipate, and that would put your forecast in good stead. Perhaps
your method is better capable of anticipating a strengthening of the
continental HP than mine is.

I didn't do a check with the 1/10 charts (one chart covers 10 days)
because it's more work and I'm short of time. It is something I can do
at a later date if necessary.

You mentioned 3 cold periods which are well worth looking at.
22nd to 27th November: I noticed HP over the continent and a large LP
to the west of Britain moving to cross the top of Scotland before
reaching the Norwegian coast. on 25th. There is a secondary with the
LP which comes into the Channel on 24th. Now this; I think, is the
coldest day of this period, because there's a chance of continental air
coming into SE England as an easterly wind round the secondary. On 25th,
HP to the west of Ireland moves eastwards bringing cold and wet
north-westerly winds into the country for the 26th. Then we have night
frost with the HP over England for 27th. So apart from the
continental inflow on 24th I can't see the bitter chill of a special
cold winter during this period.

4th to 11th December: On 4th, I noticed a bridge of HP running W/E
across the middle of the British Isles with easterly winds running
into the southern counties. After that, HP to the west of Ireland
crosses the country on 5th and 6th. And after that a litter of
depressions cross Scotland - and to the north of Scotland - during
7th to 10th, leaving Britain on 11th with pressure rising over the
country. Apart from 4th December, there is nothing out of the ordinary,
in my view, for calling this a cold period.

22nd to 25th January: On 22nd I have a complex depression coming into
western areas. There is some HP near the SE of England as a left-over
from the continent. There is a chance that the SE winds could bring
cold air in from the continent at first, but not for long. The whole LP
system moves across Scotland on 24th. A secondary LP comes into S
Ireland on 23rd and moves into the Channel on 25th with pressure
rising over the central British Isles. So apart from SE to SW winds
during most of the period I could perhaps see easterly or south-easterly
winds being possible on the 22nd, the first day and the 25th, the last
day of the period.

The 1/30 charts suggest that a few cold days could start in January,
but the main thrust looks to me like being in February, then tailing
off for March. It's not a continual cold period but a larger frequency
of short-period-chills from the continent. The LP to the NW of Scotland
is a determining factor for warmer conditions from the SW, and from
March to April this LP system appears to gain more influence over our
weather.

If your forecasting system is capable of taking into account an
above-normal intensification of the European HP - which my system is
not - then your forecast may have some chance of being partly
correct.

Cheers, Keith

Yn erthygl , sgrifennodd
Mr Blowman S@not here.karoo.co.uk:
Keith, to be honest I've followed your forecasts right through the last year
and at best I can say 50% of the time you are correct, which unfortunately
leaves the other 50%.

Sean, I'd have thought that 50% (if that's what he really achieves), given
his attention to detail, is quite a considerable achievement. Have you
verified these forecasts systematically?

Adrian

--
Adrian Shaw ais@
Adran Cyfrifiadureg, Prifysgol Cymru, aber.
Aberystwyth, Ceredigion, Cymru ac.
http://users.aber.ac.uk/ais uk