Short range model discussion - into 2018

[knocker]

Fortunately, although of course not without interest meteorologically, most of yesterdays inclement weather has travelled on with just the far north of Scotland and the Shetland Islands still being effected. The significant change of airmass is well illustrated by glancing at the last two Nottingham soundings. And as a matter of interest Nottingham did report freezing rain yesterday afternoon,

Anyway to move on with the NH 500mb and surface analysis for midnight.and the 0300 WV image

So a reasonable start to the day for most with just a few residual showers around in the north and west and this will remain the case for eastern areas but an area of more concentrated showers will effect the south west by late morning and cross England and wales during the afternoon and evening, associated with a stray occlusion. There could well be thunder and hail in the mix. Not to be left out some more intense showery activity could also effect western Scotland. Temps a marked improvement on yesterday.

The showery rain will quickly clear during the night resulting in quite a widespread frost by morning with some ice around with some fog patches but once this clears not a bad day for most, But cloud will spread from the west during the afternoon from fronts associated with another deep depression west of Ireland and rain will arrive by 1800 along with strengthening winds. Temps back to around average, maybe a tad above.

Over Monday night and through Tuesday the depression to the west, and the waving trailing front associated with it, dominates proceedings resulting in a very wet day, particularly in western regions ad a strong south westerly wind which also ensures temps a little above average.

In many ways Wednesday and Thursday are relatively quiet as the block to the east is boosted somewhat by some amplification  and thus the upper trough sits and fills over the UK. But this does result in sunny intervals and showers which again could well have hail and thunder in the mix. temps around average.

And the NH profile at T120

 

[knocker]

The 0600 chart

[knocker]

Pretty dismal down here at the moment. A lowering sheet of As with large Cu underneath with a shower in progress. The 0900 WV image

Edited December 16, 2018 by knocker

[knocker]

MODIS high res. image at 1245. The front is through here Some large Cu around

 

[knocker]

The front and rain will continue to track east this evening and overnight but not clearing the south east until the early hours. Apart from some showers in the west this will result in a clear night for most and thus some frost and icy patches by morning.

 

[knocker]

Outlook - unsettled under the influence of low pressure for the period

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

The front and rain finally cleared the south east in the early hours resulting in most places having a clear start to today, albeit with some frost and fog patches. This will soon clear and most places will have a sunny day with temps around average but by early afternoon cloud and rain from the frontal system associated with the complex area of low pressure to the west will be effecting western areas. The rain spreads north east, becoming somewhat patchy, through the afternoon and overnight accompanied by strengthening south westerly winds which could reach severe gale in exposed western areas.

As can be seen a more consolidated band of rain, associated with the cold front, is already effecting western regions by 0600 and this will track east during Tuesday bringing wet and windy weather to all apart from the south east. Squally showers behind the front but relatively mild in the fresh south westerly wind.

Some transient amplification on Wednesday ensures the upper trough remains in close proximity to the UK thus a day of sunshine and showers with temps still a tad above average.

A very similar scenario on Thursday

By Friday a complex area of low pressure covers most of the Atlantic with a new upper trough entering the fray to the west All of which results in fronts, accompanied by rain and strong winds being pushed across England and Wales on the strong flow running along the southern flank of the trough.Still relatively warm.

And the NH profile at t120

 

 

Edited December 17, 2018 by knocker

[knocker]

Pretty clear at 06, but probably some high cloud creeping in down here from the frontal system west of Ireland

 

[knocker]

Right on cue, Cs/As sheet and patchy Ac down these parts

Edited December 17, 2018 by knocker

[knocker]

High res. MODIS at 1140

[knocker]

The patchy rain will continue to generally travel north east this evening and overnight, mainly effecting western and northern regions But the cold front to the west is also continuing to track east and by 0200 the associated band of moderate rain will be effecting N. Ireland ans western Scotland. This rain will continue east through the rest of the night and Tuesday morning with only the far east of England not being effected by 1200. The rain will be accompanied by very strong southerly winds, up to possibly severe gale force in exposed areas. It's actually a fairly nifty way of following the cold front as the winds drop off sharply behind it as well as veering. Naturally frost is not a problem by morning

 

[Stuie]

After tomorrow that should be it for a week regarding gusty episodes, the potential LP for later in the week gets watered down and elongates so showers only.

I don`t mind quiet weeks at all.

[knocker]

11 minutes ago, Stuie W said:

After tomorrow that should be it for a week regarding gusty episodes, the potential LP for later in the week gets watered down and elongates so showers only.

I don`t mind quiet weeks at all.

Friday could be quite wet and windy. More detail tomorrow hopefully

[Stuie]

7 minutes ago, knocker said:

Friday could be quite wet and windy. More detail tomorrow hopefully

Could be in the South (west) and with the phasing of the LP`s I suppose still questionable.

[knocker]

8 minutes ago, Stuie W said:

Could be in the South (west) and with the phasing of the LP`s I suppose still questionable.

Yes it doesnn't look too bad looking at the ecm. Will see what this evening's fax comes up with

[Stuie]

1 minute ago, knocker said:

Yes it doesnn't look too bad looking at the ecm. Will see what this evening's fax comes up with

almost to the point of it veering NW towards Ireland/Scotland. 

[knocker]

6 minutes ago, Stuie W said:

almost to the point of it veering NW towards Ireland/Scotland. 

It's a bit complicated but if you look at the bigger picture the strongest winds are along the southern flank of the trough that is dominating the Atlantic and as the front tracks west>east across the UK Friday morning could well be over France.

[Stuie]

4 minutes ago, knocker said:

It's a bit complicated but if you look at the bigger picture the strongest winds are along the southern flank of the trough that is dominating the Atlantic and as the front tracks west>east across the UK Friday morning could well be over France.

With the SW copping most of it. Looking at 50 mph gusts?

[knocker]

8 minutes ago, Stuie W said:

With the SW copping most of it. Looking at 50 mph gusts?

Distinctly possible

[knocker]

Skimming through many of the recent posts elsewhere I'm reminded of a Tom Lehrer quote, "Apart from that Mrs Lincoln, how did you enjoy the play?"

But I digress

Outlook - continuing unsettled with low pressure influential but changes are afoot at the end of the period.

The NH 500mb and surface analysis at midnight and the WV image at 9300 which sums to current position up neatly.

The band of heavy rain associated with the waving cold front is currently effecting western regions and this will move east during the day effecting most areas by 1800. It will be accompanied by strong southerly winds, perhaps reaching severe gales in exposed western areas this morning before easing somewhat. Squally showers in the west later behind the front. Temps a tad above average.

The rain will clear into the North Sea by midnight leaving a mainly clear night but still some squally showers more particularly in the south and west

Although by Wednesday the fronts and rain have cleared the UK is still within the circulation of the main low that is filling to the north west of Ireland and troughs embedded within this will bring heavy squally showers to western and southern parts whilst the north remains relatively dry.. Temps stilt a tad above average.

This essentially remains the scenario through Thursday although the showery/rain activity is more widespread, but there are stirrings in the western Atlantic which will shortly become quite significant.

Over Friday and Saturday the aforementioned stirrings begin to manifest themselves with the Bermuda high pressure amplifying and thus the upper trough in the Atlantic taking on a more positive tilt, a prelude to becoming split and relegated to the south west. Meanwhile whilst this is going on the UK remains at the coal face of the complex area of low pressure to the west and Friday sees quite a wet and windy day in the south as a frontal system nips through giving way to showers and sunny intervals on Saturday. temps still a tad above average

And the NH profile at T120

[knocker]

Quite foul here at the moment just about on the cold front

https://earth.nullschool.net/#current/wind/surface/level/orthographic=-2.95,52.87,2223

[knocker]

Only the south east dry at 1100

[knocker]

The high res. MODIS at 1230

The MET weren't wrong when they suggested perhaps some heavy bursts of rain possible within the system. Just had a short spell of heavy rain here

Edited December 18, 2018 by knocker

[knocker]

Camborne seems to have been a wet spot this morning

http://www.met.reading.ac.uk/~brugge/12.html

[knocker]

The cold front and heavy rain belt is currently south west Scotland, NW England, east Wales and Dorset, and it will continue to track east through the rest of this afternoon an evening. clearing the east coast by midnight, It will be followed by some heavy showers which will be more concentrated in western regions of wales ans England during the early hours, Just before dawn perhaps some more thundery activity creeping into the far south east. In the cooler air behind the front some frost in northern regions.

[Stuie]

So the LP does shift N/NW and winds tamed somewhat in the South. Not a great looking day though.