Good morning. Here is the morning look at the midnight outputs from GFS, UKMO, GEM, NAVGEM and ECM and now a once a day look at the latest fax charts for today Tuesday August 27th 2013.
All models show High pressure to the SW of the UK with a broad ridge across the UK. A weak front will move SE through the ridge today with a little rain in the North giving way to a few hill showers in the West later with many areas despite a little more cloud staying dry, warm and bright. With this front gone all models show tomorrow with the ridge held firm over the UK. By Thursday and Friday winds strengthen a little from the West or NW as the ridge sinks South and a couple of fronts are shown to cross SE through these days with a little rain in the North. Over the weekend the air becomes cleaner and fresher from the NW as winds increase markedly over the north with some showers while the South though cooler will remain largely dry and rain free.
GFS then shows next week with rather more changeable conditions with a more definite Westerly flow with occasional rain for most, even the South at times. The fronts delivering these changeable conditions will continue through to the end of the run with rather cool conditions likely in the occasional bursts of NW as the fronts clear through.
The GFS Ensembles still show a dip in uppers for all at the weekend as cool NW winds take hold briefly. The recovery to well above average uppers thereafter is shown to be much more tempered this morning with the more popular outcome likely to see temperatures closer to average with rain at times in the North and at least the chance of rain periodically in the South too.
The Jet Stream continues to flow well North of the UK for a few more days. It then dives SE over the UK at the weekend with the growing trend to want to maintain this SE feed of flow over the remainder of the period with the end of run change to a more West to East flow across the UK.
UKMO today shows High pressure holding firm across the South early next week with a Westerly flow for many. A fair amount of cloud would be present nationwide but the South would likely be dry and bright while the North sees thicker cloud and occasional rain in a stronger Westerly flow.
The Fax Charts today show a series of weak fronts crossing SE towards the weekend introducing cooler and fresher NW winds and showers in the North at the weekend.
GEM shows winds from a West to NW direction early next week and like UKMO keeps fine conditions largely continuing across the South while the North would see thicker cloud, a stronger breeze and rain at times in close to average temperatures though still warm in the SE.
NAVGEM today shows a more definitive plunge of cool NW winds across all areas early next week as Low pressure pushes SE down the North Sea with cool and bright weather with blustery showers affecting all areas for a time, especially the North and West.
ECM shows stronger winds developing for all next week with dry weather for the South continuing for a time while the North sees some showers. The more unsettled and cooler conditions are shown to spread to all areas by midweek.
In Summary there seems to be a growing trend for High pressure that has been down to the SW for what seems like an age may become somewhat less influential as we move into next week. There seems to be a shift in the Jet pattern towards a more NW to SE bias next week which allows depressions to slip SE across the North Sea and NW Europe next week with the net result that the cooler and more showery conditions gradually extend deeper and deeper South into the UK. The main effect for the South is not just the increased risk of a little rain but more that the temperatures would feel a good deal fresher than of late given the inevitable increase of wind strength and cloud cover and the fact that the air to the north and NW of Britain is cooling quickly now we are into September next week.
Martin G
Kilmersdon Radstock Bath Somerset