Model Output Discussion - 14th Jan 12z Onwards

[Long haul to mild]

Steve, does the track of the initial sliding low have any effect on the subsequent Easterly? On the GFS, the front was further East, but this led to a much better Easterly flow later in the week.

If it slides further West, will that reduce the chances of an E'ly or do all roads lead to Rome!? I am hoping so.

Edited January 16, 2015 by Long haul to mild

[chicken soup]

Great news from Ian update ( sort of aligns to the raw JMA )

 

anyway here is my forecast track of the low- I will update it with model forecast tracks tomorrow.....

 

 

UK MAP.png

 

* Orange central line is my forecast track

* Two outer orange lines are the cone ( northern & Southern extent

* Inside the Blue lines is my forecast snow zone

* Inside the red circle is my forecast sweet spot

* Inside the lower red circle is the possible mixing zone ( rain sleet & snow)

* The pink lines highlights the probably adjustments-  higher probability it will be to the left of my line if anywhere....

 

regards

Steve

Thanks for that steve....probably a very dim question this but is this chart for the the slider.

[rommy19871]

Great news from Ian update ( sort of aligns to the raw JMA )

 

anyway here is my forecast track of the low- I will update it with model forecast tracks tomorrow.....

 

 

UK MAP.png

 

* Orange central line is my forecast track

* Two outer orange lines are the cone ( northern & Southern extent

* Inside the Blue lines is my forecast snow zone

* Inside the red circle is my forecast sweet spot

* Inside the lower red circle is the possible mixing zone ( rain sleet & snow)

* The pink lines highlights the probably adjustments-  higher probability it will be to the left of my line if anywhere....

 

regards

Steve

Coventry and birmingham area slighty out of your sweet spot!!

[SMU]

Steve, does the track of the initial sliding low have any effect on the subsequent Easterly? On the GFS, the front was further East, but this led to a much better Easterly flow later in the week.

If it slides further West, will that reduce the chances of an E'ly or do all roads lead to Rome!? I am hoping so.

 

Ideally the IOW exit point or a tadge further East is good -  to far best & you end up with SE winds, to far East & its Moist NE winds- so the optimum track is the UKMO one out of the 3....

 

 

S

(yes its for the slider that image)

Edited January 16, 2015 by Steve Murr

[Never snows where i live]

When is this for Steve?

Great news from Ian update ( sort of aligns to the raw JMA )

 

anyway here is my forecast track of the low- I will update it with model forecast tracks tomorrow.....

 

 

UK MAP.png

 

* Orange central line is my forecast track

* Two outer orange lines are the cone ( northern & Southern extent

* Inside the Blue lines is my forecast snow zone

* Inside the red circle is my forecast sweet spot

* Inside the lower red circle is the possible mixing zone ( rain sleet & snow)

* The pink lines highlights the probably adjustments-  higher probability it will be to the left of my line if anywhere....

 

regards

Steve

[Long haul to mild]

Ideally the IOW exit point or a tadge further East is good -  to far best & you end up with SE winds, to far East & its Moist NE winds- so the optimum track is the UKMO one out of the 3....

 

 

S

(yes its for the slider that image)

Cheers Steve, looks like I and quite a few others will be hoping that the UKMO sticks to its track!

[Mark Neal.]

With regards to Sunday Low, the UKMET model showed this on the 12z run. Pushing a bit further inland, progressive? Marginal wintry risk for those close to the south or mostly snow? thoughts?

 

Images- www.meteocentre.com 

Edited January 16, 2015 by Mark N

[SMU]

With regards to Sunday Low, the UKMET model showed this on the 12z run. Pushing a bit further inland, progressive? Marginal wintry risk for those close to the south or mostly snow? thoughts?

72.gif 72hrs.gif

Images- www.meteocentre.com 

 

HI Mark that's the fella-- although I imagine its the 78 & 84 chart where that PPN band moves East & also engages the colder air that the probability of accumulating snow arrives...

S

 

[nick sussex]

These slider lows must be  really nerve wracking for those in the firing line! We've seen how the models initially blew up the low and have now weakened this and I wonder what tomorrows trend will be.

 

Past history normally sees a correction westwards but of course theres always exceptions. In terms of tonights GFS 18hrs run you can see how even if the ECM/GFS trend is correct it needn't be some disaster for cold.

 

They may have the right overall trend but overreacted and flattened things out too much and so if theres an increase in amplitude which we've already seen on the GFS 18hrs then you'd more likely get energy disrupting and heading se under the high.

 

If you look at the expected pattern over in the USA the GFS still looks too flat even with that increase in amplitude so that's a reason to be a bit more optimistic.

 

Even before the slider low theres the uncertainty re possible snow for more southern and se areas, it would be good to see the UK squeeze in every snow possibility from the improved pattern.

Edited January 16, 2015 by nick sussex

[Mark Neal.]

HI Mark that's the fella-- although I imagine its the 78 & 84 chart where that PPN band moves East & also engages the colder air that the probability of accumulating snow arrives...

S

 

Thanks for replying, the overnight UKMO will be interesting at that timeframe. One to watch for sure, imagine you would get it on the action too!

[Mark Bayley]

Thanks for replying, the overnight UKMO will be interesting at that timeframe. One to watch for sure, imagine you would get it on the action too!

 

Interestingly this is also showed on the NAVGEM! Seems theres a possibility of a period of heavy show across the Midlands and Wales on Sunday, which is shown on the UKMO, yet nowhere to be seen on the GFS (edit: to specify, precipitation modelled much further south). Looking at all the models (GFS, UKMO, ECM, JMA, GEM, NMM, GME, COAMPS and ICON) i'd suggest this is way far north. JMA looks a reasonable shout

Edited January 16, 2015 by Mark Bayley

[Staffordshire]

Great news from Ian update ( sort of aligns to the raw JMA )

 

anyway here is my forecast track of the low- I will update it with model forecast tracks tomorrow.....

 

 

UK MAP.png

 

* Orange central line is my forecast track

* Two outer orange lines are the cone ( northern & Southern extent

* Inside the Blue lines is my forecast snow zone

* Inside the red circle is my forecast sweet spot

* Inside the lower red circle is the possible mixing zone ( rain sleet & snow)

* The pink lines highlights the probably adjustments-  higher probability it will be to the left of my line if anywhere....

 

regards

Steve

evening Steve, few questions about this graph, first the purplish lines directing away from 'the sweet spot' what is this indicating. Secondly what do you feel possible accumulations could be in the sweet spot, and also do you expect the low to pivot and stall over the sweet spot, leading to how many possible hours of snowfall?

[PolarWarsaw]

Great news from Ian update ( sort of aligns to the raw JMA )

 

anyway here is my forecast track of the low- I will update it with model forecast tracks tomorrow.....

 

 

UK MAP.png

 

* Orange central line is my forecast track

* Two outer orange lines are the cone ( northern & Southern extent

* Inside the Blue lines is my forecast snow zone

* Inside the red circle is my forecast sweet spot

* Inside the lower red circle is the possible mixing zone ( rain sleet & snow)

* The pink lines highlights the probably adjustments-  higher probability it will be to the left of my line if anywhere....

 

regards

Steve

 

Too clarify Steve - is this your thoughts for Sunday or the potential slider low pressure Tuesday/Wednesday?

[Mucka]

With regards to Sunday Low, the UKMET model showed this on the 12z run. Pushing a bit further inland, progressive? Marginal wintry risk for those close to the south or mostly snow? thoughts?

72.gif 72hrs.gif

Images- www.meteocentre.com 

 

That is from the embedded trough? interesting.

[Mark Bayley]

Too clarify Steve - is this your thoughts for Sunday or the potential slider low pressure Tuesday/Wednesday?

 

Steves graphic is in relation to Tuesday/Wednesday

[PolarWarsaw]

Steves graphic is in relation to Tuesday/Wednesday

 

Thought so - thanks!

[Cheshire Freeze]

GME the first model out of the traps this morning and it sadly goes down the pan at 132 hours...all the energy going over the sinking high. Can't post chart as on phone.

GFS almost loses heights altogether to the NE and as a result the low becomes less of a slider and introduces a larger warm sector...translates to rain and sleet in the west. Projected uppers have risen from widespread -8s a couple of days ago to nearer -4/5.

Edited January 16, 2015 by CreweCold

[The Eagle]

Well the UKMO is a bit of a disaster. GFS better but not great either. Easterly looking shakey,

[chicken soup]

Not the best of starts then to todays modeling shennanigans...i do hope were not in for a day of despondency and hand wringing, been good in here last few days.

[Cheshire Freeze]

Well the UKMO is a bit of a disaster. GFS better but not great either. Easterly looking shakey,

GFS cold but mostly dry as that mid lat high settles over us. UKMO doesn't look great at 144 as you say.

Not the best of starts then to todays modeling shennanigans...i do hope were not in for a day of despondency and hand wringing, been good in here last few days.

As I said yesterday, these things very rarely upgrade once the downgrades to longevity/potency begin. Don't get me wrong, I want to see prolonged cold and snow as much as anyone but there's no point in people denying what's infront of them. After years of model watching I'm shocked some people can't see when the writing is on the wall. So many model runs, so many repeating patterns like this!

Anyway, I'm off to bed.

Edited January 16, 2015 by CreweCold

[Mucka]

I much prefer UKMO.

GFS is rain for most from the so called slider and then cold but mainly dry. Pass.

UKMO looks like it could be quite snowy and looks like the next low could slide again.

 

Certainly little sign of the beast so far on this mornings output.

[Mucka]

GFS ensembles not trending the right way for prolonged cold and the few very cold days have been watered down a little. Hopefully this is the height of the blip and things get better again from here and at least this will still be the coldest spell of the winter with snow chances. 

 

[SMU]

Morning

I can't believe people actually get up at 430am to moan lol

I'm happy with what I have seen so far-

UKMO - - snowfest

JMA. --84 looks great

GME. -132 looks great

GFS OP - outlier esp at the key time again

ENS. -- the GFS ENS are possible the most mixed up, poorly alligned clueless ENS I have ever seen - so many off tangent by 120 I would bin the lot & start again.....

S

[snowice]

Morning

I can't believe people actually get up at 430am to moan lol

I'm happy with what I have seen so far-

UKMO - - snowfest

JMA. --84 looks great

GME. -132 looks great

GFS OP - outlier esp at the key time again

ENS. -- the GFS ENS are possible the most mixed up, poorly alligned clueless ENS I have ever seen - so many off tangent by 120 I would bin the lot & start again.....

S

Lets not panic await Ecm with interest. I think it's more consistent with setups like this,anyway by 10.30 am Gfs will more than likely flip back again.I find when you have shallow lows the placement of them is hard to model till 72hr.It's complex and it's bound to change from each run.Chin up!!! Edited January 16, 2015 by snowice

[knocker]

I have retrieved the GFS ops from the bin purely out of curiosity. Ah I see the problem. A rainfest.

 

The slider low forms a complicated low pressure area over the UK before settling for a Spanish home allowing an HP cell over the UK which although establishing quite cold conditions will be very dry. Quite pleasant. Now back in the bin you naughty outlier.

Charts courtesy weather bell

Edited January 16, 2015 by knocker