Short range model discussion - into 2018

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The intense low that will be a major influence over the next few days

 

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Through the evening and overnight the frontal rain and squally showers will dissipate, and the strong winds will abate leaving most places with a clear night and thus temps will fall giving a frost in some places. But rain and strengthening winds  from the next waving front will arrive in the west just after midnight and track slowly east.

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Outlook - during this period the UK remains under the influence of the upper trough so continuing unsettled but with temps still a tad above average

The 500mb and surface analysis for midnight and the WV for 0300

A clear and dry start to the day in many areas and this will remain the case throughout the day but cloudy in western regions with currently some patchy rain around. The rain is associated with the waving front, the movement of which will initially push this rain north east but then introduce a more concentrated belt of rain moving north along the western fringes  quite quickly during the morning, although much of this could be over the Irish Sea.

Through the evening and night the front and rain belt do eventually move east across the country

and by midday Friday both are just clearing the east coast. But to the west much is going on as detailed in earlier posts and a deep low 963mb has arrived west of Ireland by same time  This and the associated fronts will bring heavy rain and strong winds, severe gales in exposed areas, to much of the UK through Friday, but particularly western regions.

Over Friday night and through Saturday the low slowly fills and drifts north east and the fronts clear to the east leaving the UK in a very fresh W/SW wind with squally heavy showers, perhaps thundery, being, the order of the day with temps around average.

But over Sunday and Monday changes are afoot with a lobe of the Canadian vortex dropping into the north west Atlantic initiating renewed amplification in our sector which elongates the trough and brings lateral movement to a standstill

All of which means that the UK remains in the unstable south westerly airstream and a continuation of squally showers and sunny intervals with temps a tad above average

And the NH profile at T120

 

Edited November 8, 2018 by knocker

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The 0900 geostationary and the waving front to the south west

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The high res.Modis at 1320 (courtesy Dundee Satellite Receiving Station)

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The rain band is currently mainly over the Irish Sea infringing adjacent coastal areas and it will stay in western regions this evening and overnight but the main areas to be effected is complicated slightly by pulses running up the waving front as it swivels a little It will also gets quite windy over Scotland during the early hours. Clearer in the east.

[knocker]

Outlook - The UK will remain under the influence of the trough to the west for virtually the whole of the period

The 500mb and surface analysis for midnight and the WV image for 0300

The font and rain belt have been virtually stationary down the Irish Sea overnight with the rain currently concentrated over Scotland. The rain will tend to persist in this area as the front does start tracking east during the day, weakening as it goes, but by early afternoon rain and ever increasing wind, associated with the deep low west of Ireland, will encroach western regions and spread east during the afternoon. The rain will be heavy at times and the winds touching 60mph in exposed coastal regions. To the east drier and temps not bad

The rain will continue to move east during the evening and overnight exiting into the North Sea in the early hours. The strong winds will also continue for a time and it will still be squally with showers once the front(s) have cleared. Temps generally a tad above average

So come tomorrow the UK is in a fresh unstable south westerly which produces frequent showers, with hail and thunder in the mix, mainly, but not exclusively, concentrated in southern regions.

The scenario over Saturday night through Sunday is much the same, showers and sunny intervals with perhaps some longer spells of rain where the showers coalesce. Temps around average.

Essentially over Monday and Tuesday the upper trough slowly loses it's influence, although a new trough is entering the fray to the west, and Tuesday is likely to be not a bad day under a transitional ridge with plenty of sunshine with temps a tad above average

And the NH profile at T120. Note the cold Arctic plunge (vortex lobe) down eastern North America, and the strong jet , as both have a  key role to play quite shortly

 

Edited November 9, 2018 by knocker

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The 0600 chart

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A window! The rain and front have cleared here; currently a veil of As

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And as the front moves away a very brief window here with some sunshine though Cs and Ci, with some small fracto Cu. but awaiting in the wings!

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An amber warning for rain has been issued for south west Wales

https://www.metoffice.gov.uk/public/weather/warnings#?date=2018-11-09

 

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The rain has already arrived here and the wind is picking up. An overview at midday

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Not sure what that is to the west on the 1400 high res Modis. Could be the fronts nearly occluded?

Edited November 9, 2018 by knocker

[knocker]

The heavy rain and strong winds, currently over the south west, west Wales and Northern Ireland will track east this evening and overnight effecting all areas and clearing the east coast in the early hours. In the wake of the front, in the still fresh SW wind, squally showers will develop which may well have hail and thunder in the mix

And out of interest an interesting inversion and very dry area on the Camborne midday sounding that I'm taking as a frontal surface but I'm certainly open to suggestions because even if it is it doesn't really explain the dry area

 

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The Arctic plunge over North America at the moment

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Outlook - The UK remains within the circulation of the low pressure for most of the period thus a showery regime but by the end regime change is under way to calmer and drier conditions

The 500mb and surface analysis for midnight and the 0300 WV image

A drier and night for most with the wind abating with the main rain belt just clearing the east coast and some heavy showers in the west. This sets the tone for the day with frequent heavy showers, perhaps with hail and thunder, bolling in on the brisk, unstable south westerly. The midnight Valentia sounding illustrates the airmass characteristics

These could occur anywhere but there is a stray occlusion lurking within the circulation which swings north east which concentrates the showers in south western and then central and eastern regions/ Temps generally a tad above average.

Through the evening the concentrated area of showers will move into the North Sea but frequent squally showers will continue generally but more so in the south by Sunday morning

The concentrated area of showers will track north east through Sunday on the still brisk wind with temps around average

Over Sunday night and through Monday the filling low is drifting quite close to Ireland with the odd front in the circulation so still some hefty thundery showers around, probably more confined to western regions, and drier in the east with temps a tad above average.

By Tuesday the pattern change is slowly getting underway with a new upper trough tracking into mid Atlantic and some amplification of the high pressure leading to a much quieter day with plenty of sunshine on Tuesday

The amplification continues on Wednesday, albeit a front sneaks around the high to bring some patchy rain to the north west, but it is dry and quite warm with temps way above average in places,

And so on to the NH profile at T120 with the intense lobe of  the vortex about to enter stage left

 

 

Edited November 10, 2018 by knocker

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This sounding gives an idea of the instability in the south west later and one would think the convective cloud depth forecast above to be spot on

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Thunderstorm here at the moment

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with quite a violent hail shower

Edited November 10, 2018 by knocker

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Impressive  0900 sat image and we have just had another brief storm here, A snap from the earlier one

 

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The Modis image at 1120

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A nifty chart that illustrates the current position at the 200mb level

 

Edited November 10, 2018 by knocker

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With the low slowly filling at 20W west of Ireland the UK remains in the SWS airstream  thus showers. more concentrated in embedded troughs, will run north east up the country this evening and overnight

[knocker]

Outlook - for the time being the UK remains under the influence of the trough to the west but the pattern change that has been sign posted for a while does gradually get under way.

The 500mb and surface analysis for midnight and the WV image for 0300

It's been a clear might in many areas but the area of concentrated showery activity, currently over Wales and the south will swing north east through the day clearing most areas by 1800. But by that time another line of showers, associated with the approaching occlusion will effect N. Ireland.

Through the evening and overnight the showery activity peps up in northern and western regions along with a general increase of the south westerly wind

Through Monday the filling low to the west has slowly moved NW of Ireland and the associated occlusion has brought a more concentrated area of showery activity to northern and western regions and continuing quite breezy, but in the south east which doges all of this, it is quite warm

Overnight Monday and though Tuesday the low continues to fill and track north east as a ridge moves in from the south east. Thus a much better day, dry and quite warm  with temps above average.

By Wednesday the change mentioned earlier is well underway with both the Bermuda and European highs amplifying 'trapping' the trough in mid Atlantic. Which results in a very warm day with temps significantly above average but a trailing front has sneaked around the high to bring patchy rain to northern and western areas

By Thursday it's all happening to the west with another major trough entering the fray but the European high is very resilient and thus another day with temps significantly above average and dry in all areas except possible the far north west where a cold front has sneaked quite close

And so to the NH profile at T120 which is on the cusp

 

 

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As expected the rain over south Wales and central southern England at 0600

[knocker]

The area of showery activity, currently across northern Scotland, will soon clear but only to be replaced by another area embedded in the cyclonic flow that will effect N. Ireland very shortly. This will track north east during the evening and overnight, effecting n, Wales and England as well as Scotland, It will also be quite breezy in places this evening