HERE IS MY LATEST ANALYSIS USING DATA SUPPLIED BY THE NWP OUTPUT COVERING 5 OF THE WORLDS MOST POWERFUL WEATHER COMPUTERS ISSUED AT 09:00 ON TUESDAY MAR 8TH 2016
THE CURRENT GENERAL SITUATION A weakening trough of Low pressure will move Se across the UK today followed by a vigorous depression moving into Southern Britain later tonight and through tomorrow with complex troughing and gales affecting England and Wales.
http://www.wetterzentrale.de/pics/Rtavn001.gif
CURRENT SNOW FORECAST AND FREEZING LEVEL OVER THE UK The freezing level across the UK will be a little higher than recently at around 3000-3000ft especially across the South. There will be snowfall over higher ground of Scotland today and perhaps on the highest ground of England and Wales later tonight and tomorrow too as colder uppers are dragged down by heavy precipitation.
http://www.snow-forecast.com/maps/dynamic/uk
http://www.natice.noaa.gov/pub/ims/ims_gif/DATA/cursnow.gif
MODELS-2 WEEK HEADLINE Becoming less cold and mostly dry but perhaps turning rather colder again later with frost at night.
THE GFS JET STREAM FORECAST The Jet Stream currently moving South over or just to the West of the UK will end soon as pressure rises from the SW from Thursday. This will then divert the flow well to the NW of the UK in a NE direction, probably near Iceland. Through next week this arm of the flow remains well North as well as weakening with a Southern arm strengthening over Spain and Iberia. This arm then becomes the dominant one late in the period gradually edging North but all the while remaining South of the UK.
http://www.netweather.tv/index.cgi?action=jetstream
GFS OPERATIONAL The GFS Operational Run today offers a lot of fine weather across the UK in the next few weeks. The period is book-ended though by far from settled conditions at the start with a deep Low tomorrow bringing rain and strong winds to many before High pressure builds NE across the South of the UK in it's wake and then drifts slowly North maintaining fine and sometimes pleasant daytime conditions before temperatures fall back somewhat later next week under an East or SE flow though at this stage fine weather would be maintained. Then towards the end of the period High pressure declines to allow Atlantic Low pressure and fronts to edge across the UK from the SW and West with rain at times and average temperatures.
GFS CONTROL RUN The theme of the Control Run shows similar conditions under High pressure for most of the time from the end of this working week. It's position shuffles around a bit and unlike the Operational Run maintains it's influence across the UK right out to day 14 with mostly fine and settled conditions with some mild days but with a trend to reduce temperatures with time especially by night with frosts in places.
http://www.wetterzentrale.de/pics/Rtavn1441.gif
http://www.wetterzentrale.de/pics/Rtavn3841.gif
http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=144&mode=0&carte=0
http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=384&mode=0&carte=0
GFS ENSEMBLE DAY 14 DATA The GFS Clusters today show few if any clues as to where we will be in two weeks time. There is an even split between influence from both High and Low pressure near the UK with no firm theme shown today.
http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=euro&MODELL=gefs&MODELLTYP=2&BASE=-&VAR=cpre&HH=372&ZOOM=0&ARCHIV=0&RES=0&WMO=&PERIOD=
UKMO The UKMO model this morning shows High pressure building from the SW behind tomorrows deep, wet and windy Low pressure with the centre looking likely to lie just to the East of the UK with fine and settled conditions gradually developing UK wide. There could be a lot of low grey cloud in places for a while holding back otherwise mild temperatures but rainfall beyond tomorrow should become significantly less.
http://www.wetterzentrale.de/pics/Rukm1441.gif
THE FAX CHARTS The Fax Charts show slow changes across the UK in the coming 5 days. We still have 1 more inclement day to endure tomorrow under the rather cold conditions making Wednesday a very unpleasant wet day across the South in particular and I wouldn't be surprised to see more hill on it's Northern Flank as it clears. Then it's all about how quickly and decisively milder air from the SW engages with the rise of pressure occurs across all parts of the UK towards the weekend and how much influence weak warm fronts moving into the High pressure from the West interact under the High pressure likely to mean a lot of low grey damp cloud.
http://www.weathercharts.org/ukmomslp.htm#t120
GEM GEM this morning is very High pressure based with fine and settled weather developing later in the week as well as temperatures on the rise to average or maybe a little above in skies brighten. There looks to be little significant change through next week with High pressure always nearby with varying amounts of cloud determining how mild the days become and whether frost is allowed to develop by night in always light winds.
http://www.wetterzentrale.de/pics/Rgem2401.gif
NAVGEM NAVGEM looks quite similar to GEM this morning building a belt of High pressure across Southern Britain by the weekend which is then shown to extend slowly North to a previously damper North by late in the weekend and the start of next week.
http://www.wetterzentrale.de/pics/Rnvg1681.gif
ECM ECM today is a very settled one with High pressure extending across Southern Britain in a few days time and then extending to all of Britain over the weekend and beyond as the High centre drifts towards Scandinavia and then back close to northern Scotland later next week. Some early Spring warmth is possible for a time dependent on cloud amounts though a general cooling breeze from the East is likely to develop across the South of the UK with time.
http://www.wetterzentrale.de/pics/Recm2401.gif
ECM 10 DAY MEAN The 240hr mean Chart this morning continues to project High pressure lying directly over the UK in 10 days time. This being so the most likely weather would be fine and settled for most if not all of the UK and with any March sunshine it could become quite mild by day at times but still with the risk of frosts should those same cloud breaks occur overnight.
http://www.wetterzentrale.de/pics/Reem2401.gif
NOTABLE TRENDS & CHANGES FROM PREVIOUS RUNS The trend is well set for the weather to become fine, settled and less cold from the latter end of the week with solid cross model support for High pressure to build across or remain close to the UK.
31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The verification Statistics of GFS, UKMO and ECM show at 24 hours ECM ahead at 99.6 pts with UKMO at 99.5 pts and GFS at 99.4 pts. At 3 days ECM is leading with 97.6 pts to UKMO's 97.0 pts while GFS lags behind at 96.3 pts. At 5 days ECM leads with 90.9 pts to UKMO at 88.9 pts and GFS at 86.4 pts. Then at 8 Days ECM has the leading spot from GFS with 65.9 pts to 60.6 pts. Finally at Day 10 ECM has regained the lead from GFS with a score of 46.5 pts to 46.4 pts.
http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day1_PMSL_MSL_G2NHX.png
http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day3_PMSL_MSL_G2NHX.png
http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day5_PMSL_MSL_G2NHX.png
http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day8_PMSL_MSL_G2NHX.png
http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day10_PMSL_MSL_G2NHX.png
MY THOUGHTS High pressure is soon to become the dominant role player in the UK weather over the next few weeks. I'm sure most people will agree this will be a welcome change to the recent rather cold and changeable weather which has followed on the back of sometimes cloudy and wet but very mild Winter. What type of weather is likely at the surface is all dependent on what the orientation of the High pressure ends up being along with it's positioning but my best guess taken from today's output is that the South will first see the effects of fine if cloudy and milder weather on the lead up to the weekend before this type of weather extends slowly North to a rather damper North as warm fronts there cross NE on the Northern flank of the High for a time. With the High pressure migrating somewhat further North later in the weekend and next week all areas are likely to become or stay dry and probably quite bright with temperatures very respectable especially in any sunnier breaks. Having said that as the High drifts North it opens the door to a flow of air from a chillier continent and it may well be that temperatures fall back somewhat under a chilly breeze and if it stays cloudy it could feel quite raw especially near the East coast. Then as the two week period covered by this morning's output closes the theme is how and if the High pressure declines to a point that Atlantic Low pressure is allowed to return either from the SW or NW and any indicators which way the dice will fall is very unclear from the long term outputs at the moment also endorsed from the long term ensemble and cluster data available too. So recapping a couple of welcome dry and fine weeks of weather seems likely to develop and while no particularly cold weather is likely any mild or Springlike conditions remain totally dependent on whether cloud amounts become favourably small enough to a point that would also accommodate frost by night.
Next Update Wednessday March 9th 2016 from 09:00
Martin G
Kilmersdon Radstock Bath Somerset