Global model output suggests this front on a convergent trough with a
pre-frontal low-level jet (~30 m/s) will form into a sharp ana-cold
front. Expected is a core/gap morphology with Line Echo Wave Pattern
characteristics. UKMO invent output (presumably processed 1.5 km var)
is predicting such-
http://www.metoffice.gov.uk/public/p...nt/weathermap/

There is a risk of localised damaging winds and brief tornadoes.

I would be grateful if reports of damage and unusual AWS readings
could be amended here. It is important that AWS users switch to high
frequency logging. 5 min logging is insufficient to record the frontal
passage.
Time frame is 18Z 24th to 06Z 25th all of England and Wales as the
front progresses eastwards,

thanks,
David

davidDOTwaghornATgmailDOTcom

"Waghorn" wrote in message
...
Global model output suggests this front on a convergent trough with a
pre-frontal low-level jet (~30 m/s) will form into a sharp ana-cold
front. Expected is a core/gap morphology with Line Echo Wave Pattern
characteristics. UKMO invent output (presumably processed 1.5 km var)
is predicting such-
http://www.metoffice.gov.uk/public/p...nt/weathermap/


I believe it's data from the UK4 (4km) model. Could be interesting as you
indicate.

Jon.

On Tue, 24 Nov 2009 13:31:45 -0000, Jon O'Rourke wrote in


"Waghorn" wrote in message
...
Global model output suggests this front on a convergent trough with a
pre-frontal low-level jet (~30 m/s) will form into a sharp ana-cold
front. Expected is a core/gap morphology with Line Echo Wave Pattern
characteristics. UKMO invent output (presumably processed 1.5 km var)
is predicting such-
http://www.metoffice.gov.uk/public/p...nt/weathermap/


I believe it's data from the UK4 (4km) model. Could be interesting as you
indicate.

The BBC1 TV 1.25 forecast even mentioned the risk of a tornado.

--
Mike Tullett - Coleraine 55.13°N 6.69°W posted 24/11/2009 13:46:10 GMT

Mike Tullett wrote:

On Tue, 24 Nov 2009 13:31:45 -0000, Jon O'Rourke wrote in


"Waghorn" wrote in message
...
Global model output suggests this front on a convergent trough with a
pre-frontal low-level jet (~30 m/s) will form into a sharp ana-cold
front. Expected is a core/gap morphology with Line Echo Wave Pattern
characteristics. UKMO invent output (presumably processed 1.5 km var)
is predicting such-
http://www.metoffice.gov.uk/public/p...nt/weathermap/


I believe it's data from the UK4 (4km) model. Could be interesting as you
indicate.

The BBC1 TV 1.25 forecast even mentioned the risk of a tornado.


..... and at 1400 on BBC News Channel Thomas S. said "we could just about see a
mini-tornado" :-(


Norman

On 24 Nov 2009 14:07:19 GMT, Norman wrote in


The BBC1 TV 1.25 forecast even mentioned the risk of a tornado.

.... and at 1400 on BBC News Channel Thomas S. said "we could just about see a
mini-tornado" :-(

I think on the one I saw he managed to avoid the M word.

Currently there is a narrow band of heavy rain going through here, clearly
seen on the radar.

--
Mike Tullett - Coleraine 55.13°N 6.69°W posted 24/11/2009 14:38:53 GMT

"Waghorn" wrote in message
...
Global model output suggests this front on a convergent trough with a
pre-frontal low-level jet (~30 m/s) will form into a sharp ana-cold
front. Expected is a core/gap morphology with Line Echo Wave Pattern
characteristics. UKMO invent output (presumably processed 1.5 km var)
is predicting such-
http://www.metoffice.gov.uk/public/p...nt/weathermap/

There is a risk of localised damaging winds and brief tornadoes.


Current radar returns show filaments of line convection on the forward side
of the cold frontal zone extending from Newcastle down towards Penance.

Newcastle 2150Z METAR providing some ground truth in terms of heavy rain
EGNT 242150Z 26013KT 230V290 9000 +RA SCT007 BKN015 10/09 Q0985=

Jon.

"Waghorn" wrote in message
...
Global model output suggests this front on a convergent trough with a
pre-frontal low-level jet (~30 m/s) will form into a sharp ana-cold
front. Expected is a core/gap morphology with Line Echo Wave Pattern
characteristics. UKMO invent output (presumably processed 1.5 km var)
is predicting such-
http://www.metoffice.gov.uk/public/p...nt/weathermap/

There is a risk of localised damaging winds and brief tornadoes.


Current radar returns show filaments of line convection on the forward side
of the cold frontal zone extending from Newcastle down towards Penzance.

Newcastle 2150Z METAR providing some ground truth in terms of heavy rain
EGNT 242150Z 26013KT 230V290 9000 +RA SCT007 BKN015 10/09 Q0985=

Jon.

On Nov 24, 10:17*pm, "Jon O'Rourke" wrote:
"Waghorn" wrote in message

...

Global model output suggests this front on a convergent trough with a
pre-frontal low-level jet (~30 m/s) will form into a sharp ana-cold
front. Expected is a core/gap morphology with Line Echo Wave Pattern
characteristics. UKMO invent output (presumably processed 1.5 km var)
is predicting such-
http://www.metoffice.gov.uk/public/p...nt/weathermap/

There is a risk of localised damaging winds and brief tornadoes.

Current radar returns show filaments of line convection on the forward side
of the cold frontal zone extending from Newcastle down towards Penzance.

Newcastle 2150Z METAR providing some ground truth in terms of heavy rain
EGNT 242150Z 26013KT 230V290 9000 +RA SCT007 BKN015 10/09 Q0985=

Jon.

Strong winds in Wadebridge just ahead of the front. I hope I'm not in
for a sleepless few hours.

On 24 Nov, 22:27, Dawlish wrote:
On Nov 24, 10:17*pm, "Jon O'Rourke" wrote:



"Waghorn" wrote in message

...

Global model output suggests this front on a convergent trough with a
pre-frontal low-level jet (~30 m/s) will form into a sharp ana-cold
front. Expected is a core/gap morphology with Line Echo Wave Pattern
characteristics. UKMO invent output (presumably processed 1.5 km var)
is predicting such-
http://www.metoffice.gov.uk/public/p...nt/weathermap/

There is a risk of localised damaging winds and brief tornadoes.

Current radar returns show filaments of line convection on the forward side
of the cold frontal zone extending from Newcastle down towards Penzance..

Newcastle 2150Z METAR providing some ground truth in terms of heavy rain
EGNT 242150Z 26013KT 230V290 9000 +RA SCT007 BKN015 10/09 Q0985=

Jon.

Strong winds in Wadebridge just ahead of the front. I hope I'm not in
for a sleepless few hours.

I am still interested in seeing high-resolution (1 min) AWS records of
this front eg with pressure kicks of =2 hPa, strong wind gusts (25
m/s, ~50 kt) and veer at frontal passage,
thanks,
David

davidDOTwaghornATgmailDOTcom

Waghorn wrote:

On 24 Nov, 22:27, Dawlish wrote:
On Nov 24, 10:17*pm, "Jon O'Rourke" wrote:



"Waghorn" wrote in message

...

Global model output suggests this front on a convergent trough with a
pre-frontal low-level jet (~30 m/s) will form into a sharp ana-cold
front. Expected is a core/gap morphology with Line Echo Wave Pattern
characteristics. UKMO invent output (presumably processed 1.5 km var)
is predicting such-
http://www.metoffice.gov.uk/public/p...nt/weathermap/

There is a risk of localised damaging winds and brief tornadoes.

Current radar returns show filaments of line convection on the forward
side of the cold frontal zone extending from Newcastle down towards
Penzance.

Newcastle 2150Z METAR providing some ground truth in terms of heavy rain
EGNT 242150Z 26013KT 230V290 9000 +RA SCT007 BKN015 10/09 Q0985=

Jon.

Strong winds in Wadebridge just ahead of the front. I hope I'm not in
for a sleepless few hours.

I am still interested in seeing high-resolution (1 min) AWS records of
this front eg with pressure kicks of =2 hPa, strong wind gusts (25
m/s, ~50 kt) and veer at frontal passage,
thanks,
David

davidDOTwaghornATgmailDOTcom


Despite the impressive looking radar imagery the front went through Tideswell
at 2315 with barely a whimper. In the 15 minutes before the passage of the
front the wind decreased quite sharply and was less than 10 kt as the front
went through and for a time afterwards. There were no gusts of any note though
there was a short spell of heavy rain. My Davis VP gives a new pressure reading
only every 15 mins, no matter what logging interval I have set. There was a
rise of only 0.6 mb between 2300 and 2315. So, it was pretty much a non-event
here.

--
Norman Lynagh
Tideswell, Derbyshire
303m a.s.l.