Good morning everyone from another wet morning in the West Country. Here is the report from the NWP output from the midnight runs for today Saturday January 4th 2013, lifted from http://www.norton-radstockweather.co.uk/Model-Analysis(2859336).htm.
All models show an unstable SW flow across the UK with a disturbance carrying rain steadily North and East across Southern and Eastern areas through today followed by more showery conditions later. This showery flow will continue overnight though a small ridge is shown to cross giving rise to a drier window when a slight frost might develop in places. Tomorrow will see a very deep Low in the Western Atlantic throwing troughs well ahead of it over Britain later tomorrow with rain and strong winds followed by showers taking control later tomorrow and on Monday. On Tuesday and Wednesday this showery them continues as all models show the parent Low filling to the North of Scotland. Secondary features could give rise to more prolonged rainfall in the South towards midweek. Through all this period temperatures will remain largely close to the seasonal average but it could be just abut cold enough for some snow on Northern hills today and again towards midweek.
GFS then shows further troughs of Low pressure trundling Eastwards across the UK later next week in a slacker Westerly flow. With High pressure to the South these fronts could become hung up over Southern areas at times with further prolonged rain here while the North turns cooler and showery on occasion. Then later in the period a period of mild Southerly winds with rain in the West becomes replaced by further Low pressure over the UK at the end of the run with rain and showers for all.
UKMO next Friday shows a lobe of High pressure stretching from the Azores to Biscay with all of the UK in a slacker West to SW flow with troughs moving across from the West and maintaining the risk of rain or showers at times, especially in the North with temperatures remaining close to average.
GEM shows pressure building to the SE later next week with a mild Southerly flow drifting up across the UK as Low pressure areas set up shop over the Atlantic. It isn't long before troughs arrive from the West from these to affect principally Western and Southern areas then extending further North and East later.
NAVGEM closes it's run with a slack pressure gradient over the UK in a Westerly flow with slack High pressure to the South. Troughs would cross slowly East over the UK from the West at times, each giving rain at times though less heavy and frequent than what we have seen of late.
ECM today has removed it's Scandinavian High and subsequent threat of colder conditions and replaced it with High pressure to the SE and South gradually taking control. Rain on a front will eventually clear the SE late next week ahead of drier and quieter weather with overnight mist and fog and touches of frost likely with breezier and cloudier weather in the North and West with occasional rain.
The GFS Ensembles show a resilient pattern with very little change in temperatures over the whole period and a very Atlantic based pattern. All areas look like continuing to see rain at times with little in the way of frost, fog, ice or snow.
The GFS Jet Stream Forecast shows the reasons for the maintained unsettled Atlantic bias to it's track this morning as it continues to feed across the Atlantic towards Southern Britain and France through the period although some disruption is shown for a time next week which ridges it further North over the Atlantic for a time.
The ECM 10 Day Mean Chart this morning shows some support for something of a pressure rise over Scandinavia which should at least dry things up for the UK over time. Low pressure is shown biased towards Greenland keeping the UK under something of a trough and SW winds which would probably mean some rain at times most likely towards the North and West. I would suggest average temperatures the most likely result though frosts could become more frequent in the East closest to High pressure wherever it may be situated over Europe.
http://www.wetterzentrale.de/pics/Reem2401.gif
In Summary this morning we have some differences of opinion on what happens once our next week depression fills up and moves away. Most models support further troughs for a time moving in off the Atlantic to continue occasional rain up to and including next weekend. There is also reasonable support for pressure rises to the South and SE with a more Southerly feed around Low pressure in the Atlantic keeping the rain risk further towards the North and West while ECM become quite anticyclonic later though with some troublesome weak troughs to clear out of the SE first whereas GFS keeps the Atlantic monsoon going throughout. There isn't much indication from anything I have seen today to suggest a shift towards cold and wintry weather which I know cold weather fans are becoming desperate to see but for those that are looking for something drier, less windy and still reasonably mild for the time of year then your wish may be granted in a week or so time with as always in the UK a few caveats.
Martin G
Kilmersdon Radstock Bath Somerset