Short range model discussion - into 2018

[knocker]

Latest surface analysis

[knocker]

The HR MODIS showing the showers affecting western regions and the latest fax for 00 Thursday

[knocker]

And just to illustrate that it's still not resolved this morning's NOAA

[knocker]

https://earth.nullschool.net/#current/wind/surface/level/orthographic=-8.32,56.05,1350/loc=-5.597,50.211

[karlos1983]

ICON continues a southern shift by the looks of it , slightly weaker as well

 

06z12z

06z12z

06z12z

Edited January 16, 2018 by karlos1983

[tynevalleysnow]

GFS 12z for 4am Thursday 

 

[Man With Beard]

ARGEPE shows the deepening of the storm progressing as it goes through the UK, so much so that unusually the strongest winds are in the east rather than the west:

[knocker]

However this storm pans out, And I suspect some more twists, events are apparently occurring upstream that will impact the UK post the travels of the low

Two upper troughs, one from canada and the other the southern United States begin to phase together at T54 and complete the job by T84 as an intense upper low SW of Greenland that is poised to journey east and expand.

The surface manifestations of this can readily be seen with the appropriates surface charts and the 925mb temp chart is a good illustration of the tight temp gradient off the eastern seaboard which is feeding ground for cyclogenesis.

 

Edited January 16, 2018 by knocker

[knocker]

The ecm has the low over the Isle of Man at 00 Thursday.988mb and east of Hull 986mb at 0600. Max gusts south of the track probably in 50-55kt range The latest fax has it deeper and further north

Edited January 16, 2018 by knocker

[doctor32]

Still movements on track of low overnight wednesday so somewhere over ireland then northern england as above...

Winds still strong on southern flank but main concern will be the snow as this low engages colder air.

Could be some troubling snow for the rush hour in parts of NW and NE England plus parts of North Yorkshire.

Weather warnings already in place but could be up upgraded to amber tomorrow.

 

Edited January 16, 2018 by doctor32

[Sky Full]

GFS 0.25 has the strongest gusts in the Bristol Channel and English Channel between 10.00pm tomorrow and 4.00am Thursday.  

    

i confess that I don't understand what it meant by 'storm motion' but these charts also seem to relate to wind speeds?  If anyone can explain the difference I would be grateful!

    

 

[knocker]

The slight movement of the main low has tightened the gradient over the south west in the last few hours thus increasing the wind which has been gusting 55mph here

[knocker]

These complex developments off the eastern seaboard could (operative word) lead to a significant snow event over the UK

[chrisbell-nottheweatherman]

49 minutes ago, knocker said:

These complex developments off the eastern seaboard could (operative word) lead to a significant snow event over the UK

Could you possibly elaborate on the developments, please Malcolm?  From the first two outputs you posted I'm seeing low pressure just south of Greenland, but I thought that low pressure in that area tended to increase flat zonality across the UK.

Edited January 16, 2018 by chrisbell-nottheweatherman

[knocker]

2 hours ago, chrisbell-nottheweatherman said:

Could you possibly elaborate on the developments, please Malcolm?  From the first two outputs you posted I'm seeing low pressure just south of Greenland, but I thought that low pressure in that area tended to increase flat zonality across the UK.

The movement east of the upper trough will tend to flatten the ridge and the surface fronts, with a wave developing, will move north east and it's along the warm front that snow could occur if the cold pool over the UK develops at the same time. We shall see.

[ghoneym]

[knocker]

Not to spend too much time on tonight's storm as I'm sure it will be covered in detail in the regional threads so I'll settle for posting the latest fax charts (the update later to the 00 Thursday will be interesting) and this morning's Icon and to note that some adjustments may well still be made on the precise depth and location of the impacts vis wind and snow as it still has a long way still to travel today.

Regarding to day the winds and showers will abate, which is some relief as it was pretty wild down here during the night gusting 60mph., albeit the UK will remain under the influence of the complex low pressure to the north and thus still in a cold north westerly.

So on to possible events post the passage of the low which is really a follow on from yesterday's post. By T54 the upper trough over the UK is slipping South east whilst out in the western Atlantic the next troughs are leaving North America driven by the two energy flows, one from the Canadian vortex lobe and the other from the southern United States. This can clearly be seen on the 500mb and surface charts as the transient ridging of the Azores HP comes under pressure.

From this point the low to our north fills and slips down into the North Sea whilst out west the complex upper low/trough is edging east as is the associated surface wave depression (rather more north east) and the warm front which is lying NW/SE across southern Ireland by T84

The continuing pressure from the eastbound energy, particularly from the vortex lobe, continues to push the front(s) towards the UK upon which little waves are forming, and as the warm front meets the cold air then there could be a fair amount of snow in the north of England and Scotland over the weekend.

Edited January 17, 2018 by knocker

[knocker]

The updated fax chart. Perhaps a little slower and a tad further south.

[knocker]

At T96 the ecm has the warm front across southern Ireland/south west England with a very marked dew point transition so agreeing on snow along the northern edge,

[Ukwoody]

Knocker. Could you expand on tonight's storm please. My thread is one of the quieter ones and almost certainly won't be covered in any detail.  Always appreciate yours and John Holmes posts.

many thanks woody

[knocker]

11 minutes ago, Ukwoody said:

Knocker. Could you expand on tonight's storm please. My thread is one of the quieter ones and almost certainly won't be covered in any detail.  Always appreciate yours and John Holmes posts.

many thanks woody

Not sure I can expand much more UKwoody, Your best bet is keep an eye on any updates from the METO.

For what it's worth the ecm has it in the position of the latest fax at midnight, albeit not quite as deep. So the strongest band of winds will be south of the track as it moves into the North sea east of Hull. We are looking at gusts in the 60kt region and perhaps a little higher near the east coast. The sx surface chart will give you an idea of the area covered but don't forget they are 850mb winds

[tynevalleysnow]

30 minutes ago, Ukwoody said:

Knocker. Could you expand on tonight's storm please. My thread is one of the quieter ones and almost certainly won't be covered in any detail.  Always appreciate yours and John Holmes posts.

many thanks woody

John Holmes and Knocker have made this the best thread to follow. Big thanks to you both!

[Blessed Weather]

15 hours ago, Man With Beard said:

ARGEPE shows the deepening of the storm progressing as it goes through the UK, so much so that unusually the strongest winds are in the east rather than the west:

This morning's 0z Arpege continues to show this with Lincolnshire and Norfolk likely to see the strongest gusts as the storm exits the East Coast around 07.00 Thurs morning.

Not a bad performance from Arpege on the track and timing of the storm, with it's forecast holding steady for several days now, although this morning's update suggesting the area receiving the strongest winds of up to 130 km/h (80 mph) has narrowed. Widespread gusts up to 90 km/h (55 mph) for areas south of the storm track.

Arpege 0z forecast last Monday 15th:

Edited January 17, 2018 by Blessed Weather
typo

[johnholmes]

1 hour ago, tynevalleysnow said:

John Holmes and Knocker have made this the best thread to follow. Big thanks to you both!

'Tks from afar in currently snowy Wengen, hope the storm is not too severe, little info I can and initial idea re track seems not far from last fax k showed?

 

[ANYWEATHER]

Morning allWell thank goodness the storm forecast tonight is not as nearly as bad as what the models showed a few days ago. You could say it's going to be a"Storm in a teacup" but still developing as it heads towards the uk so perhaps it may be worse than forecast...ie, sting jet