Hi everyone. Here is this morning's report on the midnight outputs from GFS, UKMO, GEM, NAVGEM and ECM for today Friday September 6th 2013.
All models with the exception of NAVGEM and the outer reliable limits of ECM have changed somewhat today. Gone is the extensive build of pressure for the UK next week and in it's place is the reluctance to clear this weekends Low away East early in the week maintaining cloud and showers in much cooler conditions than of late for all for much of next week.
The Fax Charts today illustrate a cool and unsettled period to come. With winds shown mostly from a Northerly source it will feel much cooler than of late with troughs scattered around the British Isles ensuring all areas see at least some rain at times.
GFS shows Low pressure stuck out in the North Sea from Tuesday until Thursday of next week with cool Northerly winds and rain or showers in the East and more scattered showers but still cool conditions in the West. By the end of the week further Low pressure slips down from the NW keeping things cool and unsettled next weekend too in NW winds. It's only from 10 days out High pressure develops a foothold over the UK with fine , dry and warmer weather developing by day with foggy nights likely.
The GFS Ensembles show an extended cooler phase of weather now with rain at times with some recovery in uppers to more normal levels in the South late in the run as High pressure comes back on to the scene especially in the South drying things up here.
The Jet Stream shows a trough developing over the UK, one that is maintained in some form or another for the next week or so before the flow returns North of Scotland at the edge of reality.
UKMO today shows a showery trough close to SE England next Thursday with a developing Westerly flow over the North. Showers in the SE will be joined by increasing cloud and occasional rain on a westerly breeze in more northern and NW parts late in the week.
GEM does show a ridge moving across the UK from the West midweek tempering down the shower risk for a time but Westerly and then SW winds strengthen markedly as the remains of an ex-tropical depression and attendant pool of warm moist air winds up a powerful depression close to NW Scotland late in the run with the first real Autumn gales battering the North and West with heavy rain to boot to in places especially across the North and West.
NAVGEM show no such drama as it maintains it's recent theme of holding Low pressure close to Southern Britain next week with Easterly winds and thundery showers the most likely weather for the South. High pressure ridged across the North is shown to extend further South by the end of next week with fine and settled conditions for all shown by then.
ECM looks quite unsettled this morning with a slow moving Low to the East of the UK next week with rain and showers spinning South at times over the UK followed by reinforcements from the NW later on ending with a complex Low pressure area or trough across the UK with further rain or showers at times for all in temperatures close to average at best.
In Summary the embryonic downturn hinted at last night in next weeks prospects have gathered some pace this morning. We have GFS, UKMO and ECM all looking like holding Low pressure close to the East well into the middle and end of next week with the door open for reinforcements to move down from the NW by next weekend as GFS and ECM both highlight. GEM does give a 'batten down the hatches' type scenario next weekend as the remains of an ex-tropical storm gets caught up in the flow to the NW and that would mean very autumnal conditions for many. It's only NAVGEM and GFS in FI that bring some balance to the argument with fine and bright weather on offer in 10 days time as High pressure builds back over the UK from differing evolutions. So all in all still a lot of uncertainty in the mid to long term with some of the output beginning to look distinctly Autumnal if not always for the British Isles for the Northern hemisphere in general.
Martin G
Kilmersdon Radstock Bath Somerset