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 THURSDAY MAY 26TH 2016
THE CURRENT GENERAL SITUATION A weakening trough lies East to West across northern Britain moving slowly North and weakening further through the day. A slack airflow lies across Southern Britain with instability developing from the South over the next day or so as warmer continental air filters NW.
http://www.wetterzentrale.de/pics/Rtavn001.gif
CURRENT SNOW FORECAST AND/OR FREEZING LEVEL OVER THE UK The freezing level and snow forecast is now suspended until the beginning of October.
http://www.snow-forecast.com/maps/dynamic/uk
http://www.natice.noaa.gov/pub/ims/ims_gif/DATA/cursnow.gif
MODELS-2 WEEK HEADLINE Some thundery rain or showers at times but plenty of dry and fine weather too this especially in the North. Occasionally warm in the South.
THE GFS JET STREAM FORECAST The Jet Stream is expected to remain South of the UK for much of the next few weeks. It currently is blowing east across Southern Europe in association with lower pressure down there while higher pressure to the North keeps the northern arm well away to the North, also weak. It's not until the final days of the next few weeks that the flow looks like it could move back North towards the UK as pressure finally falls somewhat to the North.
http://www.netweather.tv/index.cgi?action=jetstream
GFS OPERATIONAL The GFS Operational Run today shows High pressure maintained to the North of the UK over the next 10 days or so with Low pressure to the South and SE edging up across Southern Britain early next week enhancing a thundery shower risk even more after these become prevalent at times over the weekend. Then through the second week the UK wide Easterly flow veers more Southerly as High pressure slips SE down over Northern and Eastern Britain with Low pressure over the Atlantic edging North with any rain from this restricted to the far West.
http://www.wetterzentrale.de/pics/Rtavn1441.gif
http://www.wetterzentrale.de/pics/Rtavn3841.gif
GFS CONTROL RUN The Control Run shows very similar synoptics over the first 10 days with easterly winds and a lot of dry weather for the North while the South lies at risk of thundery showers at times as Low pressure remains close enough by to the South of the UK, Unlike the Operational Run the High pressure at the end of the run remains to the North with Low pressure edging across the UK albeit rather slack with showers or rain at times for many areas then.
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 clustering today continues to show quite a mixed pattern with the bias today on higher pressure attracting a 40% cluster lying somewhere near the UK. However, this allows 60% to show a mix of options ranging from UK based Low pressure (10%) to the rest indicating an Atlantic flow from Low pressure further away to the NW.
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 unsettled weather taking us out of the Bank Holiday weekend as Low pressure from Europe drifts West across Southern Britain with rain, heavy at times in the South. With High pressure near Iceland the North would stay drier and brighter and probably warmer than elsewhere.
http://www.wetterzentrale.de/pics/Rukm1441.gif
THE FAX CHARTS The Fax Charts show the same theme of the Operational data with the main theme of instability under slack and showery conditions across the South at the weekend with the main talking point next week being the migration west from Europe of Low pressure into the South with cool and unsettled weather likely.
http://www.weathercharts.org/ukmomslp.htm#t120
GEM The theme of GEM this morning shows the easterly flow between High pressure to the North of the UK and Low pressure to the South and SE remaining the dominant weather pattern for the next 10 days. On this run the early week Low pressure moving into Southern Britain shown by other output stays to the South of the UK so the spread of general rain looks more limited so a lot of dry weather in the North over the next 10 days but a continued risk of thundery showers occurring over Southern Britain in relatively warm and humid weather.
http://www.wetterzentrale.de/pics/Rgem2401.gif
NAVGEM NAVGEM too shows a sustained period of east or NE winds between High pressure to the North of the UK and Low pressure to the South and SE with thundery showers at times especially over the South while the best weather remains likely in the far NW.
http://www.wetterzentrale.de/pics/Rnvg1681.gif
ECM ECM today is maintaining the pattern of High pressure to the North and Low pressure to the South and SE again this morning with the North seeing the brightest and warmest conditions especially towards the Highlands of Scotland. Elsewhere the risk of heavy showers and thunder at times remains a strong possibility as winds remain from an Easterly point with Low pressure near the South feeding instability up into the South of the UK at times.
http://www.wetterzentrale.de/pics/Recm2401.gif
ECM 10 DAY MEAN (12z) The 10 Day mean Chart from last night continues to show a lot of slack pressure over and around the British Isles with the risk of showers remaining in light winds and reasonable temperatures overall.
http://www.wetterzentrale.de/pics/Reem2401.gif
NOTABLE TRENDS & CHANGES FROM PREVIOUS RUNS There remains no strong desire for the models as a whole to remove Northern blocking High pressure over the next few weeks at least, leading to an East or NE flow being maintained with thundery showers in the South to remain the main theme between the models for some considerable time.
31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The verification Statistics of GFS, UKMO and ECM show at 24 hours ECM ahead at 99.5 pts with UKMO at 99.4 pts and GFS at 99.2 pts. At 3 days ECM is leading with 97.2 pts to UKMO's 96.0 pts while GFS lags behind at 95.6 pts. At 5 days ECM leads with 89.0 pts to UKMO at 86.3 pts and GFS at 85.0 pts. Then at 8 Days ECM has the leading spot from GFS with 58.4 pts to 52.5 pts. Finally at Day 10 ECM has the lead from GFS with a score of 37.3 pts to 33.7 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 Not much to be said about the models this morning that hasn't been said already in reports from previous days. The main theme is the continuation of High pressure slow moving to the North of the UK while our continental friends continue to import to the South some thundery showers at times, some days more than others. Temperatures will be well up to average or above and it will feel rather humid at times in the South. However, as always in an easterly flow North Sea Coasts will see a lot of cool and sometimes cloudy, misty weather in onshore winds while Western Scotland over the two weeks could see very little rain and maybe some of the highest temperatures in the glens. It should also be mentioned that in the early days of next week a more coherent spell of rain and cool conditions could spill west across Southern and eastern parts before the pattern resets to the North/South split in conditions again later in the week with more dry weather in the North and showers in the South. There are small hints only of a drift towards a more normal SW flow developing late in the period but hint is at far as it looks this morning so overall we have to look forward to a protracted period of warm East winds with humid air especially in the South looking likely to persist for some considerable time with the NW always looking the best place to be for guaranteed dryness and it's not often that can be said in the UK.
Next Update Friday May 27th 2016 from 09:00
Martin G
Kilmersdon Radstock Bath Somerset