Good morning folks. Here's my take on the midnight outputs from GFS, UKMO, GEM, NAVGEM and ECM for today Wednesday December 4th 2013.
All models show a change to colder, windier and brighter conditions beginning today as the first of two weak cold fronts cross SE bringing fresher and somewhat colder conditions with some sunshine later today and some frost tonight. At this time all models also show a rapidly deepening depression crossing East to the north of Scotland and then on over Europe with a fast moving cold front moving South tomorrow bringing a narrow and short-lived burst of rain followed by very much colder weather with severe gales in the North for a time along with snow showers, appreciable on Scottish mountains for a time. High pressure then builds quickly back across Southern areas and cuts off the cold feed to bring a less cold weekend and probably rather cloudy again with a little rain possible in the North for a time.
GFS then shows the High settling to the South, most likely over France with a mild SW flow over the North and West with cloud and a little drizzle possible. The South and East will share in this benign weather pattern but here there remains a risk of patchy night frost and fog should cloud breaks occur. Things then turn more changeable for all briefly with some rain possible for just about all as troughs move through before thing again return anticyclonic and benign at the end of the run and still relatively mild for December.
UKMO today closes it's run for next Tuesday High pressure well established to the SE of Britain with relatively mild Southerly winds moving North over the UK. The North and West will likely feel the full benefit of these with largely dry and cloudy conditions while the South too sees a lot of cloud too but less mild with some mist, fog and frost patches possible at times should cloud breaks drift across in association with drier continental air to the SE.
GEM shows a similar pattern to begin the week but it pulls High pressure to more northern latitudes over Europe maintaining a ridge towards Britain. This then allows colder and brighter conditions to gradually infiltrate the South of the UK from Europe with frost and fog patches night and morning while the North clings on to milder weather.
NAVGEM is virtually the same with High pressure to the East drawing up Southerly winds with the mildest air to the North and West with the same patchy fog and frost risk likely towards more South-eastern parts of Britain.
ECM keeps High pressure towards the East and SE with a slack SE flow over the South for much of the time. There looks likely to be a lot of cloud trapped in the flow but as with the other models a SE feed from Europe could carry clearer and colder air in at times with frost and patchy fog night and morning. Further North and West this looks less likely with the mildest weather likely in the NW.
The GFS Ensemble data suggests a very dry period for Southern and Eastern areas with high uppers aloft once the cold phase clears out of the way early this weekend. There is little rain shown throughout for the South with any shown transitory to a route with more High pressure.
The Jet Stream is expected to maintain a position well Northwest of the UK next week and beyond probably near Iceland offering the UK no real chance of tapping into cold conditions anytime soon with High pressure maintained over Southern and Central Europe.
In Summary today there is no chance of any real cold shown in any of the output this morning under the time span covered. This gives us two weeks in which to relax from wondering whether the atmosphere will throw anything at us that will affect any outdoor plans as after the next few days with High pressure close to the SE days of useable benign weather conditions look likely when we will be chasing areas of cloud around to allow some pleasant and relatively mild sunshine or conversely as to how much frost and fog such clearances at night will allow. Such breaks are more likely over the South and East where conditions shouldn't be overly mild but further North and West mild weather is likely and here there is more risk of occasional rain from Atlantic fronts
Originally Posted by: Hungry Tiger