"Nick" wrote in message
...
I'm surprised by the Met Office forecast for tomorrow which suggests
no clearance even in the afternoon in the south and southwest, which I
would have thought would be the case as we're into NW winds by then.
It shows heavy rain as late as 1500 and the clearance only just
getting into the southwest at 1800. Is this right? I'd have guessed
from the charts that a clearance would arrive in the southwest during
the morning and reach the central south by around midday, or mid
afternoon at the latest.


A Shapiro-Keyser cyclone often has extensive rain on the northern side of
the system due to the seclusion process. (Warm dome forming aloft). Think of
it as an upper warm front extending round
the northern side of the main "occlusion". You cannot think of these systems
like you do classical types of warm/cold/occlusion, the dynamics are quite
different. Models seem to have captured it quite well.
These systems generally form ahead of extending confluent upper troughs so
they are not rare just not as well understood.

Will
--