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 SATURDAY MAR 5TH 2016
THE CURRENT GENERAL SITUATION An occluded and weakening front across Central Britain this morning will pull away SE through the day clearing the east coast tonight and leaving a rather cold Northerly air stream across the UK for the weekend.
http://www.wetterzentrale.de/pics/Rtavn001.gif
CURRENT SNOW FORECAST AND FREEZING LEVEL OVER THE UK The freezing level across the UK will remain around about the 2000ft mark for much of the weekend but maybe a little lower than this under the occluded frontal zone at first. Snowfall amounts will be small or negligible for most through this weekend with any snow light and fleeting over higher ground exposed to the north once today's occluded front has gone.
http://www.snow-forecast.com/maps/dynamic/uk
http://www.natice.noaa.gov/pub/ims/ims_gif/DATA/cursnow.gif
MODELS-2 WEEK HEADLINE Rather cold and breezy at first with rain or showers at times with snow on hills. Then becoming less cold but windy with rain at times especially in the North.
THE GFS JET STREAM FORECAST The Jet Stream is shown to continue to blow SE or South across the UK and Western Europe in association with Low pressure moving East then SE to the North or east of the UK in the next 3-4 days. Thereafter the Thereafter the flow backs West to east across the UK late next week at least for a time before becoming less clear cut in positioning and strength towards the end of the period.
http://www.netweather.tv/index.cgi?action=jetstream
GFS OPERATIONAL The GFS Operational Run today shows the same pattern as has been shown for days now with the cold and changeable conditions giving way eventually to milder West or even very mild SW winds for a time by next weekend with rain at times towards the North. In week 2 the High pressure area to the South builds North through the UK with fine and settled weather for all. However, it looks like temperatures would fall back again with frosts at night before changeable Westerly winds return at the end of the run.
GFS CONTROL RUN The theme of the Control Run shows a variation on the same theme as the Operational today with chilly North winds backing to a milder West or SW flow by next weekend with the second week seeing High pressure build across the UK from the South or SW.
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 a bias towards Low pressure close to northern Scotland or to the NE with cyclonic winds across the UK from the West or NW the most likely option with rain or showers at times. Up to 20% of members support a more High pressure based pattern centred near to the SW of the UK.
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 has a much flatter look about it today meaning cold weather will depart to the East by midweek with a milder Westerly flow with rain at times especially across the north and West of the UK taking hold through the second half of next week.
http://www.wetterzentrale.de/pics/Rukm1441.gif
THE FAX CHARTS The Fax Charts show good support for it's operational partner with fronts orientating more West to East across the UK towards midweek with rain at times and less cold air filtering in from the West.
http://www.weathercharts.org/ukmomslp.htm#t120
GEM GEM this morning takes a different approach and instead of allowing milder westerlies midweek shows a Low pressure taking a more SE route down across the UK with more rather cold conditions with rain and hill sleet clearing as High pressure builds behind it across the South. This then extends across all areas later with dry benign days but frosty nights where skies stay clear.
http://www.wetterzentrale.de/pics/Rgem2401.gif
NAVGEM NAVGEM takes the milder route with rain spreading from the West midweek replacing the rather cold conditions until then. rain will be most prevalent towards the North and West by next weekend with milder air by then for all.
http://www.wetterzentrale.de/pics/Rnvg1681.gif
ECM ECM today returns to it's milder roots this morning following last night's changes. Therefore although mild weather is shown to take until Thursday/Friday next week to take a strong foothold once it does temperatures could exceed average levels in the South with rain from fronts more restricted towards the North and West as High pressure builds to the South.
http://www.wetterzentrale.de/pics/Recm2401.gif
ECM 10 DAY MEAN Not released at time of publishing this morning's report.
http://www.wetterzentrale.de/pics/Reem2401.gif
NOTABLE TRENDS & CHANGES FROM PREVIOUS RUNS The pattern between the models appear to be continuing to give good cross model support for a change to milder Westerly winds arriving across 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 97.5 pts to UKMO's 96.9 pts while GFS lags behind at 96.2 pts. At 5 days ECM leads with 90.7 pts to UKMO at 88.2 pts and GFS at 86.1 pts. Then at 8 Days ECM has the leading spot from GFS with 65.3 pts to 61.5 pts. Finally at Day 10 GFS has the lead from ECM with a score of 49.5 pts to 47.1 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 Things may look very different synoptically by this time next week if this morning's output is anything to go by. The main culprit of the change to milder air next week is the re-orientation of the Jet Stream which has recently been pulled South over or to the West of the UK with Britain being on the cold side of this. By the middle of next week the jet flow backs West to East over the UK or even further North with the potential for some very mild weather to threaten the South at least on a week's time. In the meantime we still have 3-4 days of rather cold and rather changeable weather to come with a little rain or even snow at times over the hills before a band of wind and rain midweek opens the door to the Atlantic. thereafter there looks to be rain at times in strong west winds for the North, but less so for the South before all areas look like becoming dry and fine at some point through the second week as there appears sound support for pressure to rise strongly then at least for a time. This may mean of course temperatures falling back somewhat again with the re-introduction of a frost risk at night but any daytime sunshine should support temperatures still approaching normal values of not above dependent on where the resting place of any High pressure may end. Towards the very end of the period the usual variability of output is shown with the favoured Atlantic westerly option hinted at returning again by the GFS model in particular. So as I said yesterday a typical early Spring mix of weather across the UK in the next few weeks but on the face of it it doesn't look that bad.
Next Update Sunday March 6th 2016 from 09:00
Martin G
Kilmersdon Radstock Bath Somerset