Short range model discussion - into 2018

[knocker]

The gfs is still indicating the previously mentioned little feature in the North Sea Tuesday morning.

[swebby]

10 minutes ago, knocker said:

Good question and first up I'm no expert on Satellite image interpretation which is quite a specialized skill. The cloud further west will be associated with the cold front but the short answer to the stuff in the Channel is I don't know, sorry.

 

It does have a ballooning appearance which i'd associate with either fog banks or something convective in nature but the sat angle may be deceptive.  I looked at the fax which made me assume fog but the GFS suggests that there is a breeze blowing in that area which makes me doubt it's fog.  I'll see if i can track down some weather buoy data.  I do like these high res sat images when we have clear cold clear skies.

Edit

Buoy info is easterly winds >10-20kts for the region so definitely not fog.  Maybe stratus that looks odd due to the sat angle

Edited February 22, 2018 by swebby

[knocker]

5 minutes ago, swebby said:

 

It does have a ballooning appearance which i'd associate with either fog banks or something convective in nature but the sat angle may be deceptive.  I looked at the fax which made me assume fog but the GFS suggests that there is a breeze blowing in that area which makes me doubt it's fog.  I'll see if i can track down some weather buoy data.  I do like these high res sat images when we have clear cold clear skies.

 

A bit tenuous but that observation in the south west approaches is indicating Cumulus.

[knocker]

More to the point what's that big hole west of Biscay on the 1200 geostationary?

[Rocheydub]

1 hour ago, knocker said:

More to the point what's that big hole west of Biscay on the 1200 geostationary?

Going to have a wild guess here.

A hole?

[swebby]

1 hour ago, knocker said:

More to the point what's that big hole west of Biscay on the 1200 geostationary?

As long as it's not a short wave spoiler

[knocker]

2 minutes ago, swebby said:

As long as it's not a short wave spoiler

Or even a trigger shortwave spoiler, heaven forbid.

[knocker]

The strong jet as you don't often see it.

[knocker]

A later MODIS at 1300 and I can confirm it is quite large Cu as some has recently drifted over here

[knocker]

With all the attention naturally turned to the east it is easy not to notice events in the west but there is no doubt the vortex/trough that has tracked south east of Greenland is very impressive, spawning a 933mb surface low, as also  is the energy that tracks south of it. Which comes to the third impressive and that is the strength of the block as it hardly budges.

The warmer air does make some headway over Saturday but the colder air from the east is already advecting in the lower layers. (fancy calculating the surface temp if you were only armed with the 850mb temp ) as can be seen.

The warmer air aloft is quickly replaced by very cold air from the east over the next 48 hours and snow showers are very likely in the east as it turns bitterly cold at the beginning of the week, complicated a tad by the little wave feature discussed this morning.

Edited February 22, 2018 by knocker

[knocker]

The ever evolving upper pattern continues apace with this evening’s anomalies. The weakening Canadian vortex is now over northern Russia and the intense high cell the tip of Greenland.  But more ridging in eastern Europe has isolated another lobe of the trop vortex from the east over western Europe whilst it is still phasing west to the trough dominating the Atlantic. This will give an upper flow from the north east over the UK but the weather detail and surface analysis is going to be tricky with the surface low in the vicinity of the UK and something once again for the det, runs to sort but perhaps a possibility of more concentrated snowfall in some areas. Temps will remain below average, perhaps still significantly so.

[Ice Man 85]

42 minutes ago, knocker said:

The ever evolving upper pattern continues apace with this evening’s anomalies. The weakening Canadian vortex is now over northern Russia and the intense high cell the tip of Greenland.  But more ridging in eastern Europe has isolated another lobe of the trop vortex from the east over western Europe whilst it is still phasing west to the trough dominating the Atlantic. This will give an upper flow from the north east over the UK but the weather detail and surface analysis is going to be tricky with the surface low in the vicinity of the UK and something once again for the det, runs to sort but perhaps a possibility of more concentrated snowfall in some areas. Temps will remain below average, perhaps still significantly so.

Am I right in thinking that this setup favours the east/south east of the country rather than the west?

[knocker]

24 minutes ago, Ice Man 85 said:

Am I right in thinking that this setup favours the east/south east of the country rather than the west?

Really impossible to pin point at this range because the position of any surface low is critical (thus the emphasis on the det, runs to sort the detail0 but the percentage play would the southern half of England, including Wales but leaning towards the east. For example the EPS 850mb mean has the surface low NW France at T180 and the Benelux countries at T216

[Ice Man 85]

2 minutes ago, knocker said:

Really impossible to pin point at this range because the position of any surface low is critical (thus the emphasis on the det, runs to sort the detail0 but the percentage play would the southern half of England, including Wales but leaning towards the east. For example the EPS 850mb mean has the surface low NW France at T180 and the Benelux countries at T216

Wouldn't want to be a forecaster right now!

[knocker]

2 minutes ago, Ice Man 85 said:

Wouldn't want to be a forecaster right now!

They haven't done a bad job up to now. The end of week does look a much better bet for snow in the south than your neck of the woods IMHO for what it's worth. Whatever it's certainly interesting despite the fact I loath cold

[FetchCB]

9 hours ago, knocker said:

More to the point what's that big hole west of Biscay on the 1200 geostationary?

Did you get to the bottom of this? 

Could it be a fallstreak hole? 

https://en.m.wikipedia.org/wiki/Fallstreak_hole

[knocker]

3 minutes ago, FetchCB said:

Did you get to the bottom of this? 

Could it be a fallstreak hole? 

https://en.m.wikipedia.org/wiki/Fallstreak_hole

No I didn't. Yes that crossed my mind but it looks far too big.

[knocker]

over the next few days the much colder weather moving across the UK from the east will become established and the general outlook relatively straightforward albeit the detail might be slightly more elusive as the days progress. Essentially most areas will be dry with plenty of sunshine but getting increasingly colder with some widespread hard to severe morning frosts and with the easterly wind picking up an increasing wind chill factor particularly in the south. Initially perhaps some isolated snow flurries in the east but becoming more frequent and heavier by the beginning of next week but mainly affecting the east and central areas.It's the detail of this that is harder to pin down and to some extent will depend on the precise wind direction.

So a little more detail.

Today and tonight dry, sunny and clear, with the wind a tad south of east, leading to a widespread frost by morning.

After the frosty start Saturday will also be dry and cold and with the wind picking up the wind chill increasing. Max temps in the 5-6C range.

Another cold night and widespread frost on Sunday morning thus heralding another dry and sunny day but getting increasingly colder with max temps in the 3-4C rage in the very brisk wind wind chill again becoming increasingly important. The wind tending to back a shade that could well impact the location, including the range inland, of snow showers as they perhaps become more frequent. This is not yet a precise science.

Similar story overnight into Monday but a more severe and widespread frost by morning and generally a much colder day with temps struggling to reach 2C and in the strong wind which is now easterly feeling bitterly cold. Some slight complication here in the north where the small disturbance over southern Norway may well influence the onshore flow in the north east. By now snow showers in the east will become more frequent and widespread and will become a radar watching issue.

Into Tuesday and a similar scenario, beginning to sound like a stuck record, and getting colder with temps in many places struggling to get above freezing so feeling bitterly cold and in the strong easterly the snow showers more frequent and probably reaching further inland and still concentrated in eastern and central areas.but not ruled out in other areas of course.Thus by Wednesday 00 the very cold air is well established

Perhaps worth a look at the 500nb pattern before we leave it and note the low to the south west

Edited February 23, 2018 by knocker

[knocker]

The ecm has a more pronounced wave feature just east of Newcastle at Monday 00 which it tracks SW to be over Liverpool by 06 Tuesday. It could well bring a more concentrated belt of snow with it. And actually the gfs is not dissimilar

 

Edited February 23, 2018 by knocker

[knocker]

Some recently updated fax charts

 

 

 

Edited February 23, 2018 by knocker

[swebby]

13 hours ago, FetchCB said:

Did you get to the bottom of this? 

Could it be a fallstreak hole? 

https://en.m.wikipedia.org/wiki/Fallstreak_hole

Looking a bit closer at the image it looks to have some counter clockwise rotation, maybe it's formed above a gyre of anomalous sst's? 

[knocker]

13 minutes ago, swebby said:

Looking a bit closer at the image it looks to have some counter clockwise rotation, maybe it's formed above a gyre of anomalous sst's? 

I've asked Dundee for their opinion so hopefully they will reply.

[knocker]

The very deep depression in mid Atlantic can clearly be seen on the very interesting midday geostationary.(image courtesy of the Dundee Satellite Receiving Station)

The06 gfs still pushing the line of snow Tuesday morning in the north

Edited February 23, 2018 by knocker

[knocker]

Another great high res, Modis image for 1145 and that cloud is drifting across here and is Cu becoming Sc.

The gfs forecast sounding in the NE Tuesday morning where the model is indicating snow.

 

[Interitus]

On 2/22/2018 at 12:13, swebby said:

 

It does have a ballooning appearance which i'd associate with either fog banks or something convective in nature but the sat angle may be deceptive.  I looked at the fax which made me assume fog but the GFS suggests that there is a breeze blowing in that area which makes me doubt it's fog.  I'll see if i can track down some weather buoy data.  I do like these high res sat images when we have clear cold clear skies.

Edit

Buoy info is easterly winds >10-20kts for the region so definitely not fog.  Maybe stratus that looks odd due to the sat angle

It was some stratocumulus or altocumulus formation, IR image shows colder than surface so not fog, but not very cold so cloud tops not high

image from Eumetsat

Edited February 23, 2018 by Interitus