Good evening. Just rescuing this thread from the very rare event of it nearly falling off of page 1 of the forum here is the evening model report taken from the 12 noon output from GFS, UKMO, GEM, NAVGEM and ECM for today Sunday September 15th 2013.
All models show High pressure returning to the British Isles tonight. Before that happens though we have to get rid of the current deep depression close to Northern Scotland first as it transfers slowly SE and fills through the week. Further wave depressions look like crossing the South on Tuesday and troughs most places on Thursday with Wednesday being somewhat showery while Friday becomes more generally dry as pressure builds up from the South with sunny spells and cool nights.
GFS shows next weekend as a warm and fine one as High pressure builds across all of the UK and with winds inherently having blown up from the SW it will be warm by day but with some mist and fog night and morning. The latter half of the run shows fine weather largely persisting across many parts but things will slowly cool down day by day to become somewhat chilly by the end of the run with some mist and fog night and morning throughout and the chance of a ground frost late in the run.
The GFS Ensembles show the operational was a warm outlier in part 2 of the run and was not very representative of a rather changeable rest of the pack. Rainfall amounts look close to average for the most part though many areas look like having a drier interlude coinciding with next weekend.
The Jet Stream tonight shows the flow continuing to flow SE across the UK as further troughs and disturbances come through the UK over the next few days. It then ridges north of the UK in response to the drier period next weekend before it settles in a West to East flow across the Atlantic and Scotland through Week 2.
UKMO has High pressure elongated across the UK from a centre over Northern Norway. The weather would be dry and bright with some sunshine and daytime temperatures close to average but cool nights with mist and fog.
GEM is a little more reluctant and less extensive in its spread of High pressure across the UK next weekend. Nevertheless the South at least would see some decent weather with any rain and attendant cloud restricted more towards the North and west at first and towards the SW in the far end of the run.
NAVGEM has High pressure developing over the top of the UK next weekend and lasting into the following week. The weather would settle down with sunny spells and light winds by day when it will feel quite warm but cool nights with mist and fog problematical night and morning.
ECM shows quiet Autumnal weather developing from early next weekend with a light westerly breeze at first before High pressure builds over the UK with fine and quiet days with some sunshine but cool and misty nights with dense fog in places, slow to clear in the mornings.
In Summary the trend towards High pressure building back over the UK shown in previous output of late has gathered pace tonight with all areas looking like settling down next weekend at least for a time as High pressure builds across the UK from centres to the SW and NE. Though some warm uppers are shown by some output others show cooler conditions with all models that show High pressure over Britain next week likely to bring mist and fog problems overnight as well as making it feel chilly in the morning's.
Martin G
Kilmersdon Radstock Bath Somerset