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 THURSDAY JULY 2ND 2015.
THE CURRENT GENERAL SITUATION A thundery trough will move North across the UK today followed by a slightly fresher SW flow for a time before humid East winds return later tomorrow in the South along with a further thundery trough.
http://www.wetterzentrale.de/pics/Rtavn001.gif
MODELS-2 WEEK HEADLINE Becoming cooler and more changeable with some rain especially in the North. Drier and warmer at times in the South.
THE GFS JET STREAM FORECAST The GFS Jet Stream Forecast shows the Jet Stream flowing North over the UK currently. Over the coming couple of weeks it remains close to the UK but veering more towards a SW to NE axis or even West to East axis late in the period.
http://www.netweather.tv/index.cgi?action=jetstream
GFS OPERATIONAL The GFS Operational today shows the recent hot weather pulled back towards the extreme SE and South over the coming days before being largely eliminated altogether later in the period. The Jet Stream is responsible flowing more and more towards a less favourable for warmth SW to NE or West to East flow across the UK in association with Low pressure to the North and West. Rain at times seems likely though with High pressure never far away to the South of the UK next week the South could still find some warmth at times between very occasional showers. Later on though all areas look like turning showery in Westerly winds with nearer to average temperarures.
http://www.wetterzentrale.de/pics/Rtavn1441.gif
http://www.wetterzentrale.de/pics/Rtavn3841.gif
THE GFS CONTROL The GFS Control run follows the operational in theme this morning with just day to day variations in the distribution of rain bearing troughs and showery spells later. It also shows that temperatures will return to average levels for all once the last embers of the European warmth leave the SE next week.
THE GFS CLUSTERS(14 Days) The GFS Clusters continue to show mixed messages with nearly all members suggesting High pressure down to the SW with some or little influence across the UK so a mixture of dry and bright weather or cloudy with outbreaks of rain or showers in temperatures close to average given winds from most members are shown to be between West and 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 UKMO today shows the heat leaving the SE at the weekend with a much more changeable look about the charts for the start of next week with Low pressure over or near the North with Westerly winds for all delivering occasional rain and showers through on temperatures close to the seasonal average.
http://www.wetterzentrale.de/pics/Rukm1441.gif
THE FAX CHARTS The Fax Charts support fresher air eventually winning the battle against the humid and very warm conditions across the SE in the coming days as Atlantic fronts push NE then East across the UK towards the beginning of next week.
http://www.weathercharts.org/ukmomslp.htm#t120.
GEM GEM today shows cooler air encroaching to all areas through the weekend and the start of next week with some showery rain likely for all. High pressure is then shown to nudge back towards Southern Britain later next week offering a return to something warmer and more settled again at least for a time.
http://www.wetterzentrale.de/pics/Rgem2401.gif
NAVGEM NAVGEM too shows a slow transition to more of an Atlantic influence with some rain at times for all in a Westerly breeze. It should be noted though that Southern Britain never lies very far away from more Summery High pressure based weather held just to the South of the UK for now.
http://www.wetterzentrale.de/pics/Rnvg1681.gif.
ECM ECM today follows the other models in gradually turning things cooler for all and not just the North and West through the weekend and next week. There will no doubt be some rain at times but probably not much in the South as Higfh pressure looks like building to the SW which would mean a return to cool NW'lies and large amounts of cloud while any rain is restricted more towards the North.
http://www.wetterzentrale.de/pics/Recm2401.gif
ECM 10 DAY MEAN The ECM 10 Day Mean Chart from last night continues to show slack pressure gradients across the UK with a Low pressure up to the Northwest and High pressure to the SW with the light West wind gradually receding the warmth slowly away to the SE with time.
http://www.wetterzentrale.de/pics/Reem2401.gif
NOTABLE TREND CHANGES FROM PREVIOUS RUNS The trends continue to suggest cooler weather for all with time as the Atlantic takes control with generally Westerly winds, average temperatures and a little rain at times.
31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The current verification statistics for the past 31 days shows ECM leading the way at 3 days with 96.1 pts followed by UKMO at 95.2 pts and GFS at 94.8. At 5 days ECM leads GFS at 84.3 pts with GFS at 82.0 pts and UKMO at 81.3 pts. At 8 days ECM clocks in ahead of GFS at 47.9 over 44.7. Then at Day 10 ECM remains ahead of GFS at 31.1 pts to 26.8 pts.
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 It seems likely now that we are slowly losing the influence of the continental heat that has affected parts of the UK in recent days. The change is a slow one with still some high temperatures to come in the SE tomorrow before a slow trend to push the high temperatures away to Europe gains momentum from the weekend. The culprit is Low pressure in the Atlantic which gradually moves towards Scotland sending cooler Atlantic borne winds across the UK. Troughs in the flow will bring rain at times next week and while fine, summery weather never looks like being too far away to the South at any point on this morning's output there is little sign of it making any big push back within the confines of this morning's runs. ECM is not so good this morning either as it shows a worrying sign of parking High pressure to the SW late in it's run and feeding relatively cooler NW'lies down across the UK in a similar way that afflicted June so much. If this morning's cooler evolutions are correct it's a good call from GFS today as it's clusters have been suggesting High pressure to migrate to the SW again in it's outer reaches for some time and with the support of ECM this morning it must be taken as a possibility of evolving. So what do we need to see the heat return. Firstly I would like to see the Jet stream move further to the North and NW of the UK rather than over us as is currently progged. In that way the Azores High to the SW or a European version to the SE could push Summer heat back our way but for the moment that's not looking likely. Secondly and alternatively I wouldn't mind seeing Low pressure slip further South in the Atlantic so that pressure could rise to the NE over the UK to set up a Scandinavian High and feed warm but not humid weather from Europe across the UK. This is the pattern which is best assured of a longer warm period that what we have recently encountered although I appreciate that eastern coastal counties folk would not like this pattern as much. Still we have what we have and while it's looking a lot cooler and fresher over the coming few weeks for many it is unlikely to be a washout and no doubt there will be some reasonable dry and warmish periods between the occasional showers.
Next update from 08:00 Friday July 3rd 2015
Martin G
Kilmersdon Radstock Bath Somerset