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 FRIDAY JAN 15TH 2016
THE CURRENT GENERAL SITUATION A cold NW flow will ease away East with a High pressure cell moving across the UK from the west over the weekend.
http://www.wetterzentrale.de/pics/Rtavn001.gif
CURRENT SNOW FORECAST AND FREEZING LEVEL OVER THE UK The freezing level across the British Isles will lie around 500m or 2000ft for much of the UK with any precipotation falling as snow over hills above 200m
http://www.snow-forecast.com/maps/dynamic/uk
http://www.natice.noaa.gov/pub/ims/ims_gif/DATA/cursnow.gif
MODELS-2 WEEK HEADLINE Very Cold and frosty with the chance of snow for a time next week then probably becoming less cold for all with some rain in the North.
THE GFS JET STREAM FORECAST The main theme of the Jet Stream today shows the Jet Stream running South across the UK over the coming days having crossed the Atlantic on an Easterly track around 50deg North. The flow then largely disrupts next week as far as the UK is concerned as it becomes much lighter and less well defined across Europe for a time before it realigns West to East across the Atlantic across Northernmost Britain.
http://www.netweather.tv/index.cgi?action=jetstream
GFS OPERATIONAL The GFS Operational Run today shows cold conditions lasting across the UK into next week as the ridge at the weekend gives way to disrupting Low pressure across the UK with an awqward mix of rain and snow moving up across the UK from the SW early next week. Thereafter High pressure re-establishes to the East for a while with chilly and drier conditions for many before the Atlantic returns later with SW winds and rain at times especially across the North and West later with temperatures closer to average or a little above at times.
GFS CONTROL RUN The theme of the Control Run is very similar in theme with the milder air not reaching many parts of the UK until later next week following a mix of rain and snow in raw conditions early on in the week. The milder SW winds then take hold but with High pressure never far away from the South a lot of dry weather is expected with rain mostly restricted to the North and West for a lot of the time.
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
UKMO The UKMO model today is once more wanting to prevent much encroachment of milder Atlantic air into the UK next week with Low pressure and troughs moving into the UK bringing an impossible to forecast mix of rain and snow across the UK at times. My own thoughts reflect on snow mostly for northern parts early in the week and perhaps the South later as the cold extends back South with a Low to the South and SW by then and an Easterly flow across the South
http://www.wetterzentrale.de/pics/Rukm1441.gif
THE FAX CHARTS The Fax Charts today show the difficult battle between cold air across the UK and Europe with milder Atlantic air moving in from the West and SW. Progress of troughs is shown to be slow and arduous with a real risk of snow for some early next week.
http://www.weathercharts.org/ukmomslp.htm#t120
GEM GEM this morning shows cold and anticyclonic conditions this weekend as High pressure is maintained close to the UK. Then through next week disrupting Low pressure near the UK brings a messy mix of rain and snow to almost anywhere for a time before it becomes drier and rather cold for a time as High pressure re-establishes to the NE. Then this is shown to collapse later with milder SW winds sending warmer air slowly NE across the UK reaching the NW first and the SE last.
http://www.wetterzentrale.de/pics/Rgem2401.gif
NAVGEM NAVGEM looks fine and settled over the weekend this morning but cold and very frosty. After the weekend Low pressure troughs move slowly into the UK from the SW with a messy mix of rain, sleet and snow for several days as Low pressure disrupts it's way SE over Southern Britain. Later next week High pressure to the East eases away SE allowing milder Atlantic SW'lies to establish late next week away from the SE.
http://www.wetterzentrale.de/pics/Rnvg1681.gif
ECM ECM today shows another variation on the same theme as the rest of the output with disrupting troughs early in the week delaying the progress of milder air into the UK with the risk of rain and snow in places early in the week. On this run a wet spell develops late next week with Low pressure zipping East across Scotland before strong High pressure ridges up from the South to end the period with a lot of dry and benign weather in average temperatures and a Westerly breeze.
http://www.wetterzentrale.de/pics/Recm2401.gif
ECM 10 DAY MEAN The 10 day mean chart shows a similar theme as it has for the last few days and I'm not entirely sure what to read from it today as I feel it is looks too simplistic on what could be a complex set of members each showing very different solutions.
http://www.wetterzentrale.de/pics/Reem2401.gif
NOTABLE TRENDS & CHANGES FROM PREVIOUS RUNS The models continue to show different options towards how long the cold weather across the UK lasts but the end theme for milder weather for all by the end of next week is still maintained 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 and GFS at 99.4 pts respectively. At 3 days ECM is leading with 97.6 pts to UKMO's 96.8 pts while GFS lags behind at 96.4 pts. At 5 days ECM leads with 90.1 pts to UKMO at 88.2 pts then GFS at 87.1 pts. Then at 8 Days ECM still leads at 66.2 pts over GFS's 63.2 pts. Finally at Day 10 ECM is ahead of GFS at 49.0 pts to 45.9 pts respectively.
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 does appear this morning as the pack of models have come dragging and screaming towards the UKMO solution that it has shown for days now although I feel the end realisation will change much more in the coming days. What we have in the short term is a strong High pressure ridge moving across the UK at the weekend although a spanner in the works is a trough up to the NW which slipping down across Northern areas at the weekend could take away the sunny skies and sharpest frosts by Sunday with some rain and snow in the North and NW. The main event though still appears to be the risk of snow and rain from the SW early next week as an ex Hurricane Alex moves North then NW across the West Atlantic. This is likely to strengthen the resolve of High pressure over or to the North of the UK and helps block the otherwise easy progress East of the associated milder air approaching the UK from the SW early next week. This means a very messy mix of rain, sleet or indeed snow could be a real risk for many next week but where and how much if any is yet to be determined. It then looks this morning that a short resurgence of High pressure from the East later next week could delay the second push of milder air too though this from most output looks much more successful in swamping all of the UK next weekend and beyond with the status quo of rain at times in the North and drier weather in the South with average temperatures at least for all by then. The models are all over the place currently and until the fragments of ex hurricane Alex have left the scene early next week we will probably continue to see further swings in outputs run to run. As a result confidence in my report comes with lower confidence than usual and things could continue to surprise us within the models in the coming days before the real solution is realised. More tomorrow.
Next Update Saturday January 16th 2016 from 09:00
Martin G
Kilmersdon Radstock Bath Somerset