Good evening. Here is tonight's look at the 12 noon outputs from the NWP for today Saturday January 18th 2014 taken from http://www.norton-radstockweather.co.uk/Model-Analysis(2859336).htm
All models show a Low pressure area out to the NW of Britain. A frontal trough will swing East across Britain tonight carrying outbreaks of rain as it goes. This will be followed with very slack conditions for all areas by tomorrow and with clear skies later frost and fog is likely with sunny spells by day and coastal showers in the West and SW. After more slack pressure on Monday freshening winds on Tuesday will develop from the SW as a new frontal systems approaches from the West with rain spreading East through the day. The front stalls and weakens over the East on Wednesday as pressure rises across it reducing the rain to drizzle through the day. On Thursday the weather looks bright and chilly as a ridge of High pressure moves slowly down over the UK from the NW.
GFS tonight shows changeable conditions for the rest of it's run tonight as further Low pressure moves East to the North of the UK then South towards NW Europe pulling winds into the North for a time with wintry showers before Atlantic Westerlies return at the end with some more rain at times but some reasonable dry periods in the South.
The GFS Ensembles tonight have drifted back into a chillier mode in the South for the second half of the run. The weather will remain very changeable with rain at times but most members show some drier spells too with breezy conditions as well at times.
UKMO next Thursday shows a ridge moving away East and allowing another trough of Low pressure to spill back in off the Atlantic later next week with rain spreading East late in the day along with freshening SW winds.
GEM tonight shows less wet weather but still very changeable conditions later next week and into next weekend and beyond. The Azores High plays a more direct effect on the weather at least in the South with rain at times, heaviest in the NW while SE Britain sees longer drier periods between shorter rainier spells. Temperatures are shown to present no real problems over the period.
NAVGEM also shows another trough bringing rain late next week along with a blustery West then NW wind as the rain turns to showers ahead of drier weather under a ridge by next Sunday.
ECM tonight shows rainfall in the South becoming a much less troublesome feature late next week as the proximity of High pressure to the SW becomes more influential. However, troughs continue to flow down from the NW with at least some rainfall for all areas but with some drier spells too with temperatures a little below average overall and rather more than just a little below average with the chance of some wintry showers of sleet or snow in places by the end of the run.
The ECM 9 and 10 day Mean Charts continue to show the most likely pattern in 10 days time of Low pressure to the NW and a very strong Azores High. Signs of pressure rises to the North remain quite limited from these charts and I would suggest the operational chart will be an exaggerated version of a potential cold outcome with plenty of members still showing an unstabe atlantic flow from the West or NW over britain.
http://www.wetterzentrale.de/pics/Reem2161.gif
http://www.wetterzentrale.de/pics/Reem2401.gif
The Jet Stream shows the flow following a similar course to that of recently with the main difference being an increase in it's strength later pushing it across Britain and then onto Europe.
In Summary tonight there is some sign of something perhaps less wet for Southern areas from later next week as the Azores High becomes more of a feature to the SW of the UK. With NW winds at times the chances of anything overly mild or cold remains quite small but the worst of the rain from the troughs continuing to afflict all areas at times will be more towards the NW or North with some decent drier spells in the South. While there is still a slim chance of a slightly colder slot of weather there is still no evidence within the time frame of anything major expected to affect the UK.
Martin G
Kilmersdon Radstock Bath Somerset