Good morning everyone. Here is how I see the outputs of GFS, UKMO, GEM, NAVGEM and ECM taken from their midnight outputs today Tuesday December 3rd 2013.
All models show High pressure moving gently South over Southern Britain today as a weak cold front sinks South over Britain with some rain in places as it comes. Behind it some clearer skies develop for a while with a patchy frost tonight before another front sweeps SE across the UK on Thursday bringing a strong to severe gale NW wind to the NE for a time. Some wintry showers of sleet and snow will affect these areas too for a time before the drier weather over Southern and Western areas at the end of the week spreas to these regions too. Over the weekend cold and frosty weather is shown to be slowly replaced by cloudy and milder conditions as High pressure is shown to slip SE across Southern Britain and on into NW Europe backing winds to a milder SW direction.
GFS then shows next week as being much milder for a time with Southerly winds wafting North over the UK around High pressure over SE Europe. In any brighter intervals it could become very mild in places. Later on though the High moves North to Scandinavia and a puddle of very chilly air is sent NW from Europe towards the UK. At the same time Low pressure off the Atlantic engages this cold air to deliver a spell of unsettled and wet weather for many and it may be cold enough for some of this rain to fall as snow for a time before the end of the run sees much more unsettled weather with rain or showers at times around deep Low pressure over the Atlantic.
UKMO shows High pressure covering much of SW Europe early next week with mild Atlantic air drifting over the UK from the West or SW. The mildest weather will be towards the North and West where the cloud will be thickest and the winds more strong while Southern and Eastern areas remain more at risk of cloud breaks at times perhaps with some mist and fog patches and somewhat lower surface temperatures as a result in very light winds.
GEM today shows a pattern we'd crave for in July as it would mean very hot weather as Southerly winds move up across the UK all the way from North Africa as High pressure settles down over SE Europe. As it is in any brighter breaks in the SE it could become exceptionally mild for early December with all areas sharing in very mild conditions at least with little in the way of rain away from the far West.
NAVGEM shows High pressure collapsing all the way down to the Med early next week with pressure falling to the NW setting up a mild and strong SW flow over Britain with troughs crossing NE with rain at times for all in temperatures close to or somewhat above average.
ECM takes High pressure only briefly away to the SE early next week before bringing it back NW in increasingly warm uppers to settle over the UK with a ridge to Scandinavia by Day 10. It looks like cloud will again be a big factor in determining conditions at the surface and it may well be that cloudy skies may keep cool conditions at the surface. However, if clouds break some very mild conditions could develop locally for a time though with patchy frost at night before more generally colder conditions begin to spread from the SE across Southern Britain at the end of the run as the UK High ridges towards Scandinavia.
The GFS Ensembles show our brief cold snap as a blink and miss it affair before we revert back to probable anticyclonic gloom as cloudy skies around High pressure to the SE looks likely for much of next week with very little rainfall for the South and East until later as things become more mobile as Low pressure edges in towards Western Britain at times with rain for all on occasion.
The Jet Stream today shows the flow to the North tilting SE down the North Sea in a day or two before resetting NE towards NW Scotland and on over Scandinavia next week keeping the UK very much on the mild side of the flow for the time being.
In Summary today if we were in Summer we would be staring down the barrel of some very high temperatures as High pressure looks like slipping down to SE Europe and sending long fetch Southerly winds from North Africa, Spain and France across the UK. Being as it's winter things are much less clear cut as cloud cover will likely set up an inversion with cloudy skies and temperatures nearer to average but largely dry, frost and fog free. However, if clouds break occur it is not out of the question for some very mild conditions to develop for a time next week with 15C or more not entirely out of the equation if the sun breaks through. Later on though there is still suggestion that High pressure rises over Scandinavia and this would gradually pull colder air from Eastern Europe towards the UK in 10-14 days time but this is an ocean of time away at the moment and must remain speculative so the UK Winter remains on hold for the time being.
Martin G
Kilmersdon Radstock Bath Somerset