On Oct 19, 11:28*am, Dawlish wrote:
Looking like this dry spell will end and not return for a while. 4
consecutive gfs runs now showing Atlantic conditions across the UK for
the forseeable future. A large Scandinavian block may delay the
progress of those lows and fronts somewhat, keeping eastern areas of
the UK drier, but that looks as if it may decline and allow in
Atlantic weather further by T240. It would need a 5th gfs run and ECM
agreement for me to forecast with confidence. Not exactly a zonal
train, but not the settled and mainly dry weather that we've become
used to. Never cold, but not particularly mild either. Autumnal
looking, I suppose - whatever exactly that means in the UK!

The possibility of a Scandinavian block that I referred to a couple of
days ago, now seems to be the preferred option at 10 days on the gfs
and ECM and GEM. It isn't being shown to decline, as the models were
suggesting then. Again, to forecast at 10 days with accuracy requires
a combination of agreement and consistency and that didn't happen. A
forecast of Atlantic dominance, back on the 19th, would probably have
proved wrong by the time the 29th came around (i.e. at 10 days).
Instead, after an Atlantic incursion, with some potential gales at the
weekend, that Scandinavian block may become the dominant element in
our weather, holding up the Atlantic, stalling fronts over the east,
keeping the east drier and keeping us all fairly mild at the month's
end. There's good agreement, over the last 18 hours but it'll still
take another couple of gfs runs and agreement with the ECM for me to
be confident that the block will occur.