"Norman Lynagh" wrote in message
...
In message , Bernard Burton
writes

snip
What I found surprising was that the Met Office forecasts yesterday were
at variance from all of the model output I looked at. Yesterday's 12z
runs of the Met Office global model, Met Office mesoscale model, GFS and
GEM models all predicted a relatively shallow "Channel runner" with
light winds over most of southern England for Monday. In contrast, the
issued Met Office 24-hour prog valid for 12z Monday showed a 973mb low
centred between Cambridge and Peterborough with a very tight gradient on
its southern flank. It seems that, for some reason, a lot of the
numerical predictions were rejected.

Norman,
Things are starting to become a bit blurred now but IIRC yesterday's 00Z and
06Z model runs had a deeper low and further north; the corresponding swathe
of strong winds extending as far north as southern England. The 12Z run then
backed off as you've noted. Based on the available information at the time
(satellite imagery/observations etc) a decision was made to stick with the
earlier model runs and the forecast products were adjusted accordingly.

It's also worth bearing in mind that some of the MetO global model runs
towards the end of last week had an even deeper low (circa 964mb) with 90KT+
gradients on the southern flank.

I'd agree with the comments regarding the GFS, it looks to have been more
consistent over the period and closer to actual events. I'm sure the experts
on the NWP side will examine this case closely as is normal practice.

Jon.