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Old September 2nd 09, 01:11 PM posted to uk.sci.weather
Dawlish Dawlish is offline
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Default High pressure and settled conditions 2nd week in September?

On Sep 2, 8:25*am, "Will Hand" wrote:
"Paul Hyett" wrote in message

...

On Tue, 1 Sep 2009 at 12:25:43, Dawlish wrote in
uk.sci.weather :


36 hours on and still looking good for a settled and warmer period of
weather next week, for England, at least. Good agreement between the
ECM and gfs. The MetO are coming round to the idea, but won't fully
commit themselves on today's 6-15 day update. I don't really blame
them. It's very easy to make mistakes forecasting at 10 days.


http://www.metoffice.gov.uk/weather/...t_weather.html


If only that set-up would wait 3 months...
--
Paul Hyett, Cheltenham (change 'invalid83261' to 'blueyonder' to email me)


Any forecast beyond 5 days needs to be taken with a huge pinch of salt at
this time of year, despite any apparent consistency. Hurricanes can develop
quickly and unexpectedly and have great potential for altering the strength
of jets and their orientation as they become extra-tropical. Also there is
at least one upper trough disruption before the forecast high pressure
period and models do not handle trough disruptions well. Confidence in an
anticyclone at this stage has to 50% at most I'd say.

Will
--


I don't know about 5 days, but any forecast beyond a week usually
needs to be taken with a huge pinch of salt at most times of the year
Will - especially when it involves forecasting a change of pattern; in
this case from very unsettled to very settled weather.

However, I have maintained for several years that there are times when
it is possible to forecast with 75% accuracy out to the far reaches
of 10 days, where forecasting usually becomes guesswork. I could be
wrong, of course (about 25% of the time), but I think this is one of
those times where it is possible. I haven't seen anything yet to
change my mind about the 10th and the MetO have certainly come around
to the same way of thinking as myself, about next week and the time
around the 10th in particular.

"Most parts are expected to become mainly dry, bright and warm around
the middle of next week" - today's 6-15 day tea-break precis! 8))