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 APR 16TH 2016
THE CURRENT GENERAL SITUATION A cold Northerly airstream has become established over the UK overnight and will continue today. Pressure will rise though and a strengthening ridge of High pressure will extend over Southern Britain tomorrow and extend it's influence further North too early next week.
http://www.wetterzentrale.de/pics/Rtavn001.gif
CURRENT SNOW FORECAST AND FREEZING LEVEL OVER THE UK The upper air temperatures are very low for April over the whole of the UK this morning at almost 1500ft in places allowing snow to fall over modest elevations across England and Wales this morning with some covering in places. This will be short-lived and after today uppers will rise to around 4000ft by Monday and higher by Tuesday.
http://www.snow-forecast.com/maps/dynamic/uk
http://www.natice.noaa.gov/pub/ims/ims_gif/DATA/cursnow.gif
MODELS-2 WEEK HEADLINE Slowly becoming drier and brighter from the weekend but with the risk of cool nights and some frost for a time next week. Perhaps more showers again later especially across the South and East.
THE GFS JET STREAM FORECAST The Jet Stream pattern is now a split flow with one portion well South over Spain and North Africa in association with Low pressure down there. Another finger is moving West to East near Northern Scotland though this flow remains quite weak. The flow to the South feeds North by midweek and sets up another period of cool North winds as pressure remains quite high at Northern latitudes encouraging the flow to remain well South of normal.
http://www.netweather.tv/index.cgi?action=jetstream
GFS OPERATIONAL The GFS Operational Run today shows a lot of cool and unsettled weather across the UK as the Jet stream remains unco-operative in supplying sustained warmer weather. The current chill Northerly will be replaced by somewhat warmer conditions for a time early in the week as pressure builds strongly across the UK. this is then eroded by low pressure moving up from the SW midweek with some potentially thundery rain here while the North stay or become largely dry and bright. Then from the end of next week on we're back to where we are this weekend with a cold North or NE flow developing. This time though it looks longer lasting than this weekend with Low pressure lying close by with a cold NE feed from Scandinavia so showers and some longer spells of rain and hill snow are still possible despite approaching May. However, High pressure is shown to win back ground to lie across the UK at the end with a warmer SE feed.
GFS CONTROL RUN The GFS Control Run although similar in sequence High pressure remains closer to the UK through the end of next week firstly restricting the extent of any spread of unsettled weather from the South and also restricting the influence of the cold and showery North feed thereafter that the Operational run above shows. Nevertheless, there will be a lot of North in the wind with High pressure stuck over the Atlantic so temperatures would still be normal or somewhat below for the most parts with the continuing risk of night frosts where skies clear.
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 still show a 75/25 split in preference of High pressure lying close to the NW of the UK in two weeks time with a chill NE flow likely to be blowing across the UK. The remaining 25% show High pressure over or to the South of the UK in an anticyclonic or Westerly feed.
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 extending it's influence from across the South to the North through next week as Low pressure begins to move up from the South or SW towards the middle of next week. Temperatures will be on the rise again though with some thundery rain possible at times across the South from midweek.
http://www.wetterzentrale.de/pics/Rukm1441.gif
THE FAX CHARTS The Fax Charts show troughs clearing South with cold Northerly winds briefly before a ridge builds across the South and then extends North early next week. Low pressure over Spain and Iberia is then shown to move North towards the South towards midweek with a warmer ESE flow ahead of it.
http://www.weathercharts.org/ukmomslp.htm#t120
GEM GEM this morning follows the same suit as the rest with High pressure early this week slowly being pushed North or NW as Low pressure to the South edges up towards Southern Britain strengthening an Easterly flow which eventually turns to a chillier North or NE'ly as High pressure establishes to the west and NW. Northern and Western parts would likely stay dry with night frosts while the South, East and particularly on this run the SE stay cold and breezy with showers or rain at times.
http://www.wetterzentrale.de/pics/Rgem2401.gif
NAVGEM NAVGEM also shows the same build of pressure in the coming days, firstly across the UK before it gets sucked away NW to Greenland by the end of the run opening the door to cold NE winds and heavy showers to sweep South to all parts by next weekend, this following a period when Southern England could have some thundery rain from a Southern European trough moving North midweek.
http://www.wetterzentrale.de/pics/Rnvg1681.gif
ECM ECM today still shows the same theme as it and i't ensemble dats have shown for days in that the current cold day today will be replaced by a period of benign and settled weather lasting several days with temperatures recovering for many. However, Low pressure is shown to try and push North towards Southern Britain midweek with the risk of some showery rain. While this is happening High pressure over the North at the end of next week is sucked away to the NW near Greenland with a cold and showery NE flow developing across the UK although the NW lying close to the ridge from the Greenland High might stay dry. Frosts at night look very likely under any clear skies late in the period
http://www.wetterzentrale.de/pics/Recm2401.gif
ECM 10 DAY MEAN (12z) The 240hr mean Chart from last night continues the theme of High pressure likely over the Atlantic in 10 days time with Low pressure to the East or SE meaning a cool Northerly or NE'ly flow likely over the UK with some showers by day and frost by night
http://www.wetterzentrale.de/pics/Reem2401.gif
NOTABLE TRENDS & CHANGES FROM PREVIOUS RUNS Still too much emphasis on the trend for cool and showery North or NE winds to be blowing down across the UK in 10-14 days time for my liking. However, that is the main trend this morning.
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 99.3 pts. At 3 days ECM is leading with 97.4 pts to UKMO's 96.8 pts while GFS lags behind at 95.6 pts. At 5 days ECM leads with 89.6 pts to UKMO at 87.5 pts and GFS at 84.2 pts. Then at 8 Days ECM has the leading spot from GFS with 65.1 pts to 60.2 pts. Finally at Day 10 ECM has the lead from GFS with a score of 42.6 pts to 39.2 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 It still looks far from ideal Springlike conditions for gardeners and growers this morning as they will despair at the amount of High pressure shown in the models this morning all in the wrong places to eradicate the risk of night frosts almost anywhere in the UK over the next 10-14 days. A notable frost is expected for all tonight as today's cold Northerly is replaced by a strong ridge of High pressure. This then gently feeds North in the following days to allow some warmer air to develop in the sunshine with the first few days of next week looking very respectable. However, we have not lost the Low pressure down to the South and towards midweek troughs from that edge up towards the South with potentially thundery rain likely for a time. This then looks like being pulled away to the East as not unlike this weekend a surge of colder air is pulled down from the NE as pressure retreats towards the NW Atlantic and Greenland. These NE winds would likely bring a mix of bright sunshine but some big and very cold April showers with soft hail, thunder and sleet all in the mix I would suspect and no doubt somewhere could see snow. As a result of this flow nights would be clear and cold inland with frosts likely but in compensation in the sun between the showers it should feel OK. The NW would probably see the best weather overall but having said all of the above the overall weather pattern is not concerning in the amounts of wind and rain totals but as I live in an area of avid gardeners and growers they will be disappointed that I am still talking frosts and cold showers at this stage in Spring rather than dry and warm ideal Spring conditions. However, I can only say what I see and lets hope that the models turn around in a days or so to take us out of this Northern blocking situation that has eluded us all Winter which not unsurprisingly has decided to turn up in Spring this year.
Next Update Sunday April 17th 2016 from 09:00
Edited by user
Saturday, April 16, 2016 8:50:27 AM
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Reason: Not specified
Martin G
Kilmersdon Radstock Bath Somerset