HERE IS MY LATEST ANALYSIS FROM THE OUTPUTS OF THE WEATHER COMPUTER PREDICTION MODELS FOR TWO WEEKS FROM 8AM TODAY FRIDAY NOVEMBER 14TH 2014.
NEXT UPDATE SATURDAY NOVEMBER 15TH 08:00
THE CURRENT GENERAL SITUATION A large depression covers the Atlantic ocean with the centre filling slowly and drifting towards SW England over the weekend. An active trough will slowly clear NE to lie over NE Scotland tomorrow.
MODELS-2 WEEK HEADLINE Remaining largely unsettled with rain at times, heavy in places, especially later in the NW and coupled with spells of strong winds in near to average temperatures for all.
THE JET STREAM ENSEMBLE FORECAST The GFS Jet Stream Ensemble forecast is shown to weaken over the coming days splitting as one arm blows East across the Arctic while the other remains diffuse to the South of the UK. The Southern arm then becomes the dominant force again later next week, crossing the UK before moving further North around our neck of the hemispher to lie North of the UK at the end of the run.
GFS OPERATIONAL The general message from the GFS operational this morning is for mild and changeable weather maintained across the UK after a quieter chillier period early next week as Low pressure becomes slack across the South. A much stronger Westerly flow develops thereafter with gales in the North and West with rain, heavy at times too for all though as pressure is shown to build to the South for a while at the start of Week 2 the South could see drier and mild conditions for a time.
THE GFS PARALLEL RUN The GFS Parallel run is shown to become much more dominant across the UK in Week 2 as after a week of unsettled and sometimes wet and windy weather replaced by dry and fine weather in light winds. A warm High is shown to engulf the UK in Week 2 with cloudy and misty conditions likely at the surface. Then very late in the run more unsettled and colder weather looks poised to come down from the North with rain and wind in tow moving North to South.
THE GFS ENSEMBLES. The GFS Ensembles are very similar to the operational run in sequence and trend with the run ending in High pressure having built across the UK with some frost and fog patches replacing the wet and windy Atlantic based weather in the preceding days.
UKMO. UKMO today continues to show another Low pressure out to the West through the middle of next week filling slowly again as winds stay largely light and from a mild Southerly quarter. Rain will occur on occasion but with some drier spells too especially over the East where some parts could stay dry with some fog at night.
THE FAX CHARTS The Fax Charts show a gradually slacker airflow developing across the UK as a parent Low to the West drifts towards the South of the UK and fills by the start of next week. Troughs to the NE persist and showery ones near the coasts of the South will continue to blight the far South in slowly less mild weather with fog in places.
GEM GEM also shows a sustained period of slacker winds as Low pressure areas to the West fill as they move SE towards the SW of the UK with a light South or SE flow likely with rain and showers more restricted to near an old trough close to the NE at first and the far South throughout. Late in the run the Atlantic ratchets up a few gears with stronger winds and rain spreading steadily East across the UK by Day 10.
NAVGEM NAVGEM shows changeable conditions over the coming week as the High pressure block to the NE collapses later with a shift in distribution of rain and wind moving more towards the NW later as a SW flow develops across the UK in fairly mild conditions.
ECM ECM this morning has again shifted from it's last run with the unsettled and slack pressure gradient over the UK through much of next week being replaced by a real bullseye of a storm system over the UK by next weekend delivering severe gales and heavy rain for all as a result, all this following the collapse of the High pressure block to the NE by then. This then sets up a strong Westerly flow thereafter with further troughs carrying rain and strong winds quickly East over all areas at times in average temperatures.
THE ECM ENSEMBLES The Ensembles point to a strong chance of a deep depression lying close to SW Iceland in 10 days time with a strong SW airflow covering the UK in what would produce rain at times for all in relatively mild conditions.
NOTABLE TREND CHANGES FROM PREVIOUS RUNS The trend continues to show variations on a theme of basically mild and changeable weather in a largely Westerly flow with rain at times, the emphasis of which shifts more towards the North and West with time.
MY THOUGHTS The main message delivered from the models this morning continue to suggest that the UK will see little if any particularly cold conditions over the next few weeks as the basic flow of winds remain from either Southerly or Westerly latitudes. In the short term the High pressure block still dominant to the NE prevent deep Low pressure areas crossing the UK from the West with attendant fronts and rain stalling over the UK and delivering the most unsettled conditions toward the South and West. Later in the period most output suggests the block to the NE collapses and pressure may become higher towards a position South or East of the UK shifting the emphasis of rain towards the North and West but also permitting more mobility across the North Atlantic as a stronger Jet flow is likely to lie across the UK by then powering up deep Low pressure areas to the NW with rain and gales for all at times as a result. The position of any higher pressure to the South of the UK will be indicative of how much of the wind and rain from these Lows affect the South but a more certain fact is that if High pressure does develop there it will be mild for all and once developed can become a real fixture for a sustained period but as for now this is a minority view. My own personal viewpoint is that it will stay relatively mild for the foreseeable future with many ingredients for cold becoming increasingly displaced with time shifting the emphasis of concern towards how much rain will be falling on already saturated ground over the period. I think what we are lacking this season is cool High pressure which can sometimes develop at this time of year introducing early Winter cold to our shores in the shape of frost and fog failing to clear by day rather than cold weather from any other source this early on. However, as things stand apart from the risk of cool fogs this weekend in some parts there is little sign of any significant chill for the UK shown from any source today.
Martin G
Kilmersdon Radstock Bath Somerset