Model output discussion pm 13/01/2016

[Cheshire Freeze]

Something like this is the very VERY best we could get from this situation. Though literally everything would have to go right

[Alexis]

00z ARPEGE http://www.meteociel.fr/modeles/arpege.php showing snow for some out of nowhere all of a sudden

 

[SMU]

Another spectacular GFS fail on the cards for the UK

yest 156 12z

 

Todays 00z 144

The signal overnight is a strong swing to cold - without scouring the ENS the JMA is my favourite

S

Edited January 15, 2016 by Steve Murr

[Cheshire Freeze]

4 minutes ago, Steve Murr said:

Another spectacular GFS fail on the cards for the UK

yest 156 12z

 

Todays 00z 144

The signal overnight is a strong swing to cold - without scouring the ENS the JMA is my favourite

S

Aye and the most positive thing I take from the overnights? Well the GFS in FI may not be on the money as other models and a few of the GEFS present a much more robust Siberian HP which should serve to keep the GFS FI horror show at bay....

[jvenge]

Hi Mucka. Did the 72-96 range settle down yet?

[Cheshire Freeze]

9 minutes ago, Greenland1080 said:

NAVGEM at T132

If this HP gains any more latitude we'll be looking at an easterly!

[Cheshire Freeze]

ECM 96 hour

UKMO 96 hour

Big differences at just 4 days out

 

[Cheshire Freeze]

3 minutes ago, Greenland1080 said:

Interesting ECM120

My thought....we're teetering on the brink of an easterly with some some of the modelling this morning.

[shaky]

Massive improvements from pretty much all the major models this morning!!did say yesterday expect the ukmo to be right!!let the upgrades continue!!

[Ali1977]

29 minutes ago, shaky said:

Massive improvements from pretty much all the major models this morning!!did say yesterday expect the ukmo to be right!!let the upgrades continue!!

Not sure on the improvements, yes the Atlantic isn't rolling in and a block of sorts holds, but the 850s within the block beyond Monday are much less cold with no chance of snow. Nights would still be chilly however.

Edited January 15, 2016 by Ali1977

[chris55]

Re Monday's front. GEM is probably most pleasing this morning. We need that negative tilt to draw in some continental air , as opposed to the more positive tilt like GFS, which would mix in more maritime air. 

But with the general theme of undercutting as we get closer to verification hopefull GFS will trend more towards GEM

 

 

[winterof79]

First port of call was METO forecast this morning.Even the most seasoned followers on here were being swayed in to making false predictions due to the unique situation.SM apart I should say.As is always the case on our little Island,surprise snowfalls have and will happen when our cold pool exerts itself.

I expect a major frontal snow event at some stage next week and then as GP and Tamara allude to,a colder Feb.Enjoy folks and try to pick the pick the meat off the bones by examining all output including fax charts as above,

Crewe how much brass did you wager last night

[Chris1986]

Alex upgraded to hurricane on the final approach to greenland. Could be one for the history books. 

[chris55]

17 minutes ago, Ali1977 said:

Not sure on the improvements, yes the Atlantic isn't rolling in and a block of sorts holds, but the 850s within the block beyond Monday are much less cold with no chance of snow. Nights would still be chilly however.

Yea, it's Sunday's slight positive push on the high from the Atlantic creating that rain sleet and snow for the north that's causing the problem. Hopefully we can get a backing west of the slightly colder 850s into Monday if the undercut/potential slider can get south and west

 

[Chris1986]

Gfs has the hurricane modelled incorrectly in strength and path It would appear. 

[cyclonic happiness]

21 minutes ago, winterof79 said:

First port of call was METO forecast this morning.Even the most seasoned followers on here were being swayed in to making false predictions due to the unique situation.SM apart I should say.As is always the case on our little Island,surprise snowfalls have and will happen when our cold pool exerts itself.

I expect a major frontal snow event at some stage next week and then as GP and Tamara allude to,a colder Feb.Enjoy folks and try to pick the pick the meat off the bones by examining all output including fax charts as above,

Crewe how much brass did you wager last night

The 'snow' event on monday is showing as a rain even on the euro, seems to sweep the uppers away far too easily. I hope it's wrong.

[bluearmy]

23 minutes ago, Chris1986 said:

Alex upgraded to hurricane on the final approach to greenland. Could be one for the history books. 

That's ex tropical Chris.  

modelling still not quite settled down re next week. still looks like a toss up between a snowy occlusion or a snow to rain one.  on the rails remains the the disrupting front moving NE and then petering out against the block. 

[Shuga ice]

Well it's coming!  The milder weather that is.  This chart is a good example of the slow erosion of the high from the north west.  Unfortunately this is the wrong angle of approach for any snow to last.  So currently it is looking like a mainly dry weekend with rain, sleet, snow approaching the northwest, then slowly sliding down the country with the southern half staying mainly dry for most of next week.  Still some night frosts for the south whilst the north stays mild and damp.  With the way the charts have been recently, the outlook could look entirely different on the next set of runs.

[Nick F]

In all my 15 years of following the output, apart from early on in the naughties - when NWP was more fickle than now, don't think I've seen such big swings from the high res and the ens at such close range.

Goes  to show that changes from run to run in the initial starting data in certain key areas upstream, such as the unusual and sudden development of a hurricane in Jan mid N Atlantic, can bring such big run to run inconsistency.

Dont be surprised if GFS flips back to a less favourable outcome later, just to keep the stress levels up and down!

Edited January 15, 2016 by Nick F

[Chris1986]

3 minutes ago, bluearmy said:

That's ex tropical Chris.  

modelling still not quite settled down re next week. still looks like a toss up between a snowy occlusion or a snow to rain one.  on the rails remains the the disrupting front moving NE and then petering out against the block. 

Yes ex tropical, either way hurricane force, I'd prefer to trust the national hurricane center path and strength predections. Gfs doesn't seem to match the noaa for location speed and strength. I think this could be an interesting development all the same.

[Penrith Snow]

23 minutes ago, chris55 said:

Yea, it's Sunday's slight positive push on the high from the Atlantic creating that rain sleet and snow for the north that's causing the problem. Hopefully we can get a backing west of the slightly colder 850s into Monday if the undercut/potential slider can get south and west

 

Curious, the MetO website has snow for here for Saturday afternoon and night but no mention of it on the Beeb forecast? One to watch.

Andy

 

 

[MR EXTREMES]

12 minutes ago, bluearmy said:

That's ex tropical Chris.  

modelling still not quite settled down re next week. still looks like a toss up between a snowy occlusion or a snow to rain one.  on the rails remains the the disrupting front moving NE and then petering out against the block. 

It's my birthday today my name is Chris I'm 41 and I've never seen a hurricane track straight north ever.

ive got a feeling cold will stay around possibly milder in our location sunny Costa south coast.

but great news I'd of thought although I'm no expert but warming event in the strat perhaps because of the Atlantic tropical storms up tick surely.

[IDO]

I usually like to comment about post D7 developments but having to refrain at the moment with such complexity and variety cross and inter model, its just best to wait and see how the near and now develops.

What GFS did pick up was that wave of amplification from the Azores that is now around D6. All models showing this apart from UKMO that sends a spin off low off the Atlantic trough; not sure about that?

ECM:GEM: GFS:

How that rise in pressure reacts with the HP in situ has the models flummoxed! Can it help develop a HLB or will we see a UK MLB? All models have an active trough to the west so what strength of forcing to the pattern will that have? The models also vary with the PV profile and Arctic heights by D10. So lots to resolve and more questions than answers. I agree with Mucka that no model has been great and that is what you would expect when there is entropy; lots of clusters and the OP moving between these clusters run to run. We just have to accept that Atlantic trough -v- UK high -v- Euro trough -v- Russian/Siberia High is a hard combo to model.

FWIW, as I said a couple of days ago, a UK/Euro ridge/high looks strongly modelled from week 2 and the GFS mean still going that way supported by Week 2 CFS and JMA:

CFS:    JMA:   D12 GEFS Mean: 

If I was to make a call I couldn't really ignore this as it is currently the clear consensus so a return to milder than average and N/S split?

[Daniel*]

Cold week ahead on GFS gradually turning milder from west for parts of SE/EA it remains cold until the end of the week, however there would be no snow with uppers. 

Monday to Saturday - 

[Weather Observer]

I was fascinated by that UKMO day 6 chart last night. It could have led almost anywhere. Worst, it could have been the sink hole down which our cold weather dreams were to disappear.

Now I can see rabbits coming out of a hat. You can analyse this to bits, but whatever the outcome, the Met and their models have been remarkably consistent while the other models have been all over the place.

 

Edited January 15, 2016 by Weathervane