Hi everyone. Are the synoptic charts bringing what the cold fraternity want this morning. Read on to see what the midnight outputs from GFS, UKMO, GEM, NAVGEM and ECM make of the cold weather potential this morning Friday November 15th 2013.
All models to continue to agree on the course of events of the next 5 days with a spell of quiet and benign weather today, tomorrow and much of Saturday too in the South as pressure is very high to the SW. There will be some chilly and frosty conditions overnight across England and Wales while skies stay cloudier in the far West and North. Later tomorrow a band of rain on a front moves South through Scotland and on South to England through Sunday. Following behind is a more active front on Monday which heralds the arrival of a cold NW flow with showers turning wintry across Northern and Western areas in particular during Tuesday while many Eastern and SE areas become largely dry, bright, breezy and cold.
GFS then shows low pressure developing over the North of the UK which sinks South through Southern England and away further South by the end of the week. A spell of cold rain will slide South over Southern britain with some wintriness over the hills. The north will brighten following sleet and wet snow with sunshine and wintry showers in a keen and strong East flow for a time. By next weekend High pressure has developed South over Scotland with clear, cold and very frosty weather here while the South stays cold, cloudy and windy with occasional light rain. Through the latter stages of the run this morning the fine and cold weather over the North extends to all areas with fog developing too, dense and freezing in places. Temperatures by day begin to rise and later milder air reaches the North with cloudier skies but mostly dry weather while the South clings on to quiet and settled weather with night frost and fog.
UKMO this morning shows very cold weather through the middle of next week with a Northerly flow having swung NE midweek with wintry showers giving way to the threat of more prolonged rain, sleet or wet snow for a time across the South while the NW become drier, cold and more settled with time.
GEM this morning is less interested in a Northerly as such as it brings an innitial push of cold air South prior to midweek with wintry showers in the North and West Tuesday with drier weather for all for a time midweek. Late in the week more deeply unsettled conditions turn up from the North and with chilly air around widespread rain and strong winds will fall as sleet or snow at times, especially on northern hills. The depression responsible ambles around over Southern Britain while filling slowly before a new Low approaches from the SW by the end of the run with wet and windy weather spreading NE with sleet and wet snow possible over hills on its leading edge.
NAVGEM today shows probably the best synoptics long term if it's sustained cold weather your after with Low pressure sinking South across England later next week and away to the South by the weekend when a strong Easterly flow brings raw cold and windy weather with rain, sleet or snow in places, especially over the hills. The North would slowly be turning drier by next weekend but still cold as a High pressure belt lies to the North.
ECM today has broke away from the pack with the innitial cold surge dissolving away to just a day or two of wintry showers, chiefly over the North and West before a ridge dries things out with a frosty interlude midweek. After a brief lull though cold weather does re-intensify later in the week as High pressure is finally allowed to build to the NW with a deep Low close to SE Britain brnging rain, sleet or snow at times across the UK late next week and the weekend with the NW likely to stay the driest then with overnight frosts.
The GFS Ensembles show a marked lowering of uppers for a time next week before the coldness dissolves to levels closer to average later in the run. Rainfall is commonplace throughout the period once the cold weather arrives indicating the close proximity of Low pressure. Some of the precipitation could fall as snow on the hills at times lessening in it's extent with time.
The Jet Stream shows the flow way North of the UK currently turning South over the UK to set up a new arm across Southern Europe next week while the Northern arm detaches and weakens. The Southern arm then becomes the dominant Jet flow remaining South of the UK later in the run.
In Summary there are a few wobbles in the output this morning especially from ECM which just highlights the fragility of the setup needed to bring guaranteed cold to the UK. The main problem is the models failure currently to handle energy moving out of canada preventing an otherwise straightforward passage Northward to the Atlantic High. This morning it is not until that Low has passed that finally ECM plays catch up with the remainder of the output. Nevertheless, despite this the emphasis on this morning's output is a cold one and there is a fairly good chance that some areas will see some snow next week. The extent of such as always is open for controversial debate but I would urge caution for those looking for a white wonderland next week there seems little evidence to excite me that anywhere other than the highest moors of the South will see much with lower ground in the North too just seeing transient temporary slushy falls. However, we are only in mid to late November and such conditions are relatively marked for this time of the season so a surprise or two could be in store for some folk almost anywhere if some of this mornings more extreme charts verify.
Transcript taken from:-http://www.norton-radstockweather.co.uk/Model-Analysis(2859336).htm
Edited by user
Friday, November 15, 2013 8:41:10 AM
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Reason: Not specified
Martin G
Kilmersdon Radstock Bath Somerset