Good evening. Here is the report on the 12 noon outputs from the NWP for today Saturday December 21st 2013.
All models continue to show a very volatile spell of weather on the road to Christmas with a very showery day tomorrow especially in the West followed by a thoroughly awful day on Monday as a vicious area of Low pressure winds up close to NW Britain with severe gales and storm force gusts affecting some areas through the day along with heavy and locally torrential spells of rain. Following this there will be heavy and squally showers rushing through on the wind with hail, thunder, sleet and snow all possible on Christmas Eve. Through Christmas Day and Boxing Day lighter winds look likely with showers more scattered as a result and confined to coastal areas adjacent to the breeze with some areas ending up dry and bright if rather cold.
GFS then exits Christmas with another active storm system sending strong winds and gales across the UK which only relaxes slowly as we move towards the end of the year. By New Years Eve another Low is formed close to Western Britain with more wind and rain for many areas which quickly clears NE in time for New Years day which looks much better and quieter across most areas. Changes then towards the end of the run revolve around rising pressure from the Southeast sending and weakening rain bearing systems towards Northern and Western areas while England and Wales become much quieter and drier if somewhat colder.
UKMO tonight shows post Christmas opening with another very powerful storm system to the North of the UK with strong to gale force WSW winds and heavy rain having cleared East to be replaced by showers with once more some wintry showers on hills and in the North.
GEM tonight shows unsettled and innitially stormy conditions soon after Christmas with storm force winds, heavy rain then squally and wintry showers with hail and thunder all thrown in at times. Winds do die sown towards the end of the year but the weather looks likely to remain cold and unsettled as we hit the New Year period with another Low pressure down to the SW and with pressure over Europe less in a hurry to rise.
NAVGEM shows very stormy weather a week from now with gale SW or West winds showers and longer spells of rain and showers, wintry on hills.
ECM tonight shows unsettled and sometimes stormy weather continuing right up to the New Year with nowhere immune from some very unpleasant conditions at times. Heavy rain will be all too frequent with some colder brighter weather with showers, wintry on hills in between the rain bands in temperatures close to or a little above average at times in the South later.
The GFS Ensembles show another disappointing set with average uppers throughout and spells of heavy rain all too frequent with sunshine and showers in between with wintry showers over the hills.
The Jet Stream shows the flow slipping South of the UK as we approach and over Christmas itself before it moves back North over and occasionally just to the NW of the British Isles towards the end of the run.
In Summary there is still an awful lot of newsworthy weather to get through before any of the models show anything of significant improvement over the coming period and even then there is still plenty of scope for further wind and rain to take us into the New Year. Temperatures in themselves will be close to average overall though this will be sufficiently cold enough for some snow over hills at times. The wind will also be a major feature with another worrying storm likely just after Christmas before things do look like moderating somewhat in terms of wind strength while rainfall build up could continue to be a problem throughout the period. Unfortunately for those looking for something rather traditionally colder and wintry will have to continue to wait as there still remains little signs of any major change to the overall pattern anytime soon while the Jet stream profile remains as it is.
Martin G
Kilmersdon Radstock Bath Somerset