"Nick" wrote in message
...
I've noticed the Met Office is advising a weather advisory for
Saturday morning for the south of England for heavy rain, but that
doesn't seem to tie in with the pressure charts: GFS and ECM suggest
some rain going through Friday night (after midnight, so technically
morning I guess) then some more after dark on Saturday - the Met
Office pressure charts suggest the same but the low moving in from the
SW after dark on Saturday seems to be absent. So where do they get
Saturday morning from?

Nick

Nick. a band of locally heavy rain will spread NE tomorrow in association
with the occlusion/cold front depicted on the 12Z T+48
http://www.wzkarten.de/pics/brack0a.gif
Further rain is then expected to spread up from the south in association
with the development running up from Biscay at T+60
http://www.wetterzentrale.de/pics/brack1a.gif

What perhaps isn't so obvious is a risk of snow on the occlusion overnight
tomorrow across Wales and parts of central/northern England as the front
runs up against colder air in the north. The main risk is over high ground
but with time it could quite easily descend to low levels on Saturday
morning
as the wet-bulb freezing level lowers close to the pivoting front. Something
to keep any eye on anyway..

Jon.