HERE IS MY LATEST ANALYSIS USING DATA SUPPLIED BY THE NWP OUTPUT COVERING 5 OF THE WORLDS MOST POWERFUL WEATHER COMPUTERS ISSUED AT 08:00 ON SATURDAY MARCH 14TH 2015.
THE CURRENT GENERAL SITUATION A cold but slack East to NE flow will affect all areas with a ridge over Scotland.
http://www.wetterzentrale.de/pics/Rtavn001.gif
MODELS-2 WEEK HEADLINE A lot of dry weather with some sunshine and just occasional rain especially at first in the South and in the North later. Temperatures will be close to average or a little below overall.
THE GFS JET STREAM ENSEMBLE FORECAST The Jet Stream Ensemble Forecast shows the the main thrust of the flow moving North across the Atlantic, Iceland and the Norwegian Sea. Meanwhile a Southern arm over North Africa and towards Eastern Europe around a cut off Spanish Low continues for a time before a strong Northern arm develops across the UK later, at least for a time in the second week.
http://www.theweatheroutlook.com/twodata/datukgfshires.aspx?display=jetstream&model=gfs
GFS OPERATIONAL The GFS operational run today shows a lot of High pressure based weather, firstly over Europe giving the UK a spell of cold East winds and later over the UK with more sunshine, lighter winds and night frosts most likely at that time. It then shows a much more mobile, windy and unsettled period developing in the second week under active Atlantic Low pressure with strong winds and rain or showers at times in typical March conditions later.
http://www.wetterzentrale.de/pics/Rtavn1441.gif
http://www.wetterzentrale.de/pics/Rtavn3841.gif
THE GFS CONTROL The GFS control run is similar in sequence of events through the next week or so but the unsettled Westerly period shown by the operational is a colder NW'ly from the Control Run leading to cold and windy weather with wintry showers for a time at the start of the second week before High pressure makes a comeback at the end of the period in cold air with bright and pleasant enough days but with sharp Spring night frosts.
THE GFS CLUSTERS The GFS Clusters show a predominance of Low pressure expected to lie close to the UK in two weeks times with variabtions of cloudy, wind and rain or showers under Low pressure near to, just to the NE or West between 65% of the pack. The remaining 35% show High pressure lying across the UK with fine and settled conditions
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 UKMO this morning shows the ridge from the East slowly being replaced by our own UK High pressure through the week with rather brigter skies by day and frost by night. By the end of the working week this looks like being edged slowly West as pressure falls towards Scandinavia.
http://www.wetterzentrale.de/pics/Rukm1441.gif
THE FAX CHARTS The Fax Charts show a complex area of High pressure stretching a ridge West over the UK but complicated by weak troughs moving West or NW in the flow before a UK based High pressure begins to simplify the fine weather pattern by midweek or soon after.
http://www.weathercharts.org/ukmomslp.htm#t120.
GEM GEM today shows High pressure in control over the UK in the shape of a ridge from the East at first or a High centred across the UK later in the coming week. There is a chilly NE or East feed across the South for much of the cold adding to a chill feel here before sunnier conditions across the North later this week raise temperatures by day somewhat. Things are shown to become more delicately poised between slack winds and slightly more unsettled conditions by the end of the 10 day period covered by the run.
http://www.wetterzentrale.de/pics/Rgem2401.gif
NAVGEM NAVGEM shows High pressure becoming dominant and centred across the UK later this week and maintained until the end of the run with the current chilly East flow becoming replaced by less cold and sunnier air for many but with a frost risk at night.
http://www.wetterzentrale.de/pics/Rnvg1681.gif.
ECM ECM this morning shows a complex and slowly changing High pressure based pattern over the next week to 10 days. There are threats of even colder air than we have currently making inroads into the SE of the UK from the NE as the Euro High is replaced by a UK based one just to the NW but on this run it fails to sustain it narrowly as the High collapses SE and a slow change to less cold Westerly winds look likely towards the end of the 10 days, first in the North.
http://www.wetterzentrale.de/pics/Recm2401.gif
ECM 10 DAY MEAN The 10 Day Mean Chart this morning continues it's drift to a more changeable Atlantic based weather pattern by Day 10 with aJet Stream South of the UK, Low pressure close to the North and a Westerly flow across the UK no doubt with rain at times.
http://www.wetterzentrale.de/pics/Reem2401.gif
NOTABLE TREND CHANGES FROM PREVIOUS RUNS The collapse of the European High next week is well supported with the evolutions thereafter gradually showing more of a tendeny for Atlantic Westerly winds and rain at times to develop slowly.
31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKM & ECM The current verification statistics for the past 31 days shows ECM leading the way at 3 days with 97.8 pts followed by UKM at 97.3 pts and GFS at 96.7. At 5 days ECM continues to lead the field at 91.2 pts over UKMO at 89.2 pts and GFS at 87.9. At 8 days ECM remains the leader with 67.8 pts over GFS's 62.7 pts. Then at Day 10 ECM retains superiority at 51.0 pts over GFS at 46.2.
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.prig
MY THOUGHTS The mist is slowly clearing between the model outputs this morning as there looks like a cessation in the chilly East or NE from all but the Southernmost part of the UK by midweek as a new UK based High pressure is looking highly likely by then. This should clean up the European haze into clearer skies with some sunshine but with frosts at night where skies clear sufficiently. Then as we look further out still there are varying scenarios in the way that High pressure declines over the UK with the majority edging towards a more Atlantic influence taking hold, probably from the North or NW with much more likelihood of bands of rain and showers beginning to turn up across the UK from pressure having fallen pressure from the North. The extent and longevity of this change is difficult to call at this range with the longest term output indicating that there is a chance that High pressure may return late on but too speculative to call a defintive 'yes' at this range. So all in all a fairly settled and benign weather pattern looks likely over the next 10 days or so with light winds gradually swiching to a less cold quarter with time and rather more sunshine coming into play too once our UK based high develops. A chance then of more unsettled and changeable conditions with average temperatures is then conceivable late in the period but all in all nothing too dramatic and concering weatherwise across the UK in the next two weeks with temperatures finishing up having been near or slightly below average overall.
Issued at 09:00 Saturday March 14th 2015
Martin G
Kilmersdon Radstock Bath Somerset