Good morning folks. Here is the report on the midnight outputs of GFS, UKMO, GEM, NAVGEM and ECM for today Sunday October 6th 2013.
The General Situation. All models are in fairly sound agreement on the course of events over the next 5 days or so. A High pressure area in the English Channel is bathing Southern areas of England and Wales in fine and dry weather today with sunny spells making it feel warm after the clearance of chilly early morning mist and fog. Further North winds are more defined from the SW with cloud and patchy rain at times, heavy in the NW. Through the next few days the North will stay changeable with some rain at times and the South will become cloudier but still mostly dry until midweek. High pressure then is likely to transfer towards the West and NW of the UK allowing a cold front in association with Low pressure moving South to the East of Britain to bring a spell of light rain to all followed by much colder and brighter skies. This then sets up a much colder regime than we have seen thus far this Autumn with sunny spells by day but very chilly night when frost and fog become probable, more so in the North and West. The South and East may become rather chilly and unsettled by next weekend as showers from a Continental Low advances across from the East. Winds are expected to freshen too from the NE accentuating the cold feel here.
GFS then shows the UK remaining under cooler and more changeable conditions thereafter with the Atlantic bringing further Low pressure in to join our own home based model during Week 2 with rain at times and temperatures lower than of late. The rain could be heavy at times with strong winds locally.
UKMO shows High pressure up to the NE of the UK with a ridge towards Scotland next weekend. Southern England would be afflicted with a chilly and strong ENE flow with cloudy skies and the risk of a little rain at times in association with a Low pressure area over the near Continent. Mist, frost and fog would be likely in the North.
GEM holds High pressure closer in, over NW Britain next weekend limiting the effects of any cool NE flow over the South for a while longer before it too shows it making inroads into the UK from the East early the following week with some showers and temperatures close to normal. Cool night would result in mist, fog and a touch of frost too. that most likely in the NW.
NAVGEM concludes it's run with High pressure receding East over scandinavia with a ridge to Scotland weakening. An Easterly drift is shown to be strengthening over Southern britain with cloudy, grey skies likely and temperatures having fallen back to average late this week. Again mist, fog and a touch of frost are all possible by night, especially in the North.
ECM brings a strong ENE flow over the South at the end of the week which would no doubt feel cold under the likely cloudy skies with occasional rain as Low pressure settled close to the SE. the north would stay dry and brighter close to receding High pressure to the NE with bright days and the chance of mist, fog and frost patches by night. At the end of the run the winds have decreased as pressure has become slack over the UK with a few showers still floating around in misty and rather cloudy conditions as well as quite cool conditions too overall.
The GFS Ensembles show a marked drop in uppers midweek behind the cold front. thereafter a slow recovery to more average conditions at the surface look likely with occasional rain or showers following a fine start to this week. in the South. No huge amounts of rain are indicated though by any model at this range and certainly not much in the way of strong winds considering we are well into October.
The Jet Stream to the NW of Britain is now expected to turn sharply South over the UK midweek with a cut off Low developing close to the SE with the main flow well North of the UK over Iceland and Northern Scandinavia. There are signs thereafter this morning that ot could realign much further south towards Southern Europe in week 2.
In Summary a change to the weather is on the way. The models were quite late in picking up this change but have now all come together in their prognosis. A cold front slipping South on Wednesday will pull in much colder Autumnal air to all areas. The North and West close to repositioned High pressure close by will become dry with the early week rain having moved away while Southern areas though dry for a while become under attack from Low pressure over Europe which looks like feeding rather cold raw and perhaps strong NE winds and occasional rain or showers. Longer term it looks like changeable conditions will ensue with not much sign of a return to the current warm uppers across Britain though it doesn't look like turning particularly chilly as yet. Nevertheless, some areas particularly in the North could see their first frosts of the season later this week but at least with the injection of drier air midweek fogs look less likely to be widespread from this morning's output.
Transcript taken from:-http://www.norton-radstockweather.co.uk/Model-Analysis(2859336).htm
Martin G
Kilmersdon Radstock Bath Somerset