Winter Model Discussion 18Z 16/1/13 onwards.

[chionomaniac]

GFS well out of kilter with the UKMO and ECM with position of the block compared to the other two by day 6. And with its recent reliability I think that we should stick with the UKMO and any model that follows this as a realistic guide to the 6 day outlook.

PS I think we have seen this before already this year!!

Edited January 16, 2013 by chionomaniac

[Timmytour]

The cold block of uppers to the North east seems to be coming down a little further to the east on this run.....could that be what's weakening the block a little and allowing the atlantic in a bit later?

[lorenzo]

Having sent the shortwave to Biscay at T126, the GFS is trying to work out how to get the Azores High into the UK. Bin.

GFS not deepening an Atlantic low on approach? It must be ill.

It's scared of unleashing this corked up cold..

[Snowmadsam]

Well the NAE is great for western area and for some of it is very special!

I am hoping for further snow now....but lets see

[pages]

Ok 18z is awful for us in the south east compared to the euros, the precip on Friday a lot lighter then sinks the block with massive low at t144. 18z no gaps goes with ECM Bom JMA ukmo. Big differences at t30 so we will know by tomorrow night if the gfs has gone off on one

[bluearmy]

The T120 fax shows the ultimate sliding trough. Judging by recent modelling, it wont look like that in 24 hours.

[chionomaniac]

Ok 18z is awful for us in the south east compared to the euros, the precip on Friday a lot lighter then sinks the block with massive low at t144. 18z no gaps goes with ECM Bom JMA ukmo. Big differences at t30 so we will know by tomorrow night if the gfs has gone off on one

It's so off on one that I have stopped looking at it from T+144 onwards.

[nick sussex]

It looks a real struggle here for the precip to get far east.

These westwards corrections historically aren't a surprise and the models often underestimate the block to the east, certainly nerve shredding for those on the peripheries.

Certainly impossible to call where the snow/dry and snow/rain zone will end up. I've been here before many times when I was living in London and it was like pulling teeth to get the snow to get a move on eastwards.

Even upto the day you just never know what will happen and how much precip will be ahead of the front, I think its best to wait for the morning runs to see if this westwards trend continues.

[Froze were the Days]

GFS just goes the way of previous runs - after 'jumping ship' yesterday on the 12z it's strange how it's gone back to it's usual power through the block regime (which it had maintained for days) - there does seem a period where this model around the 120z mark doesn't seem to know where to go but stays remarkably the same for a day or so and gives us a 'col'.

[Captain Shortwave]

When the shortwave goes under on Monday, you get a split in the depressions. Yet again another choice, does energy go north or south. Logically, like all the other models do, the energy keeps going south into France. GFS, yet again decides to send energy north flattening the high a returning atlantic conditions.

My faith in this model is falling through the floor (unless its right of course)

Edited January 16, 2013 by Captain shortwave

[samadamsuk]

The T120 fax shows the ultimate sliding trough. Judging by recent modelling, it wont look like that in 24 hours.

yeah interesting chart that one - it seems like the 850's wrapping around it are more potent than what the block is sending across us - looks like snowfest to me -

[Harsh Climate]

Not liking the way the GFS keeps banging the 'mild breakdown drum'!

It's been wrong for the last week or so, so let's hope it's wrong again!

[bluearmy]

Is anyone really watching the 18z? I have a feeling no one believes the 06z and 18z gfs runs to the extent they are treated like nogaps!

[mountain shadow]

Have to say Nick, the Met Office will have to re-write the warnings based on the 12z and 18z runs, across the board the precipitation stalls in the west which is a great improvement for western areas.

Have The Met Office become to reliant on the model output. Many on here have mentioned how fronts used to struggle east against a block yet it seems The Met Office have not considered it.

[chionomaniac]

It's so off on one that I have stopped looking at it from T+144 onwards.

It even ignores it's own 100hPa profile at T+144!!

[Long haul to mild]

GFS creates plenty of room for its live-in-lover, the Azores high to ridge in yet again next week on this run. It's so tedious and predictable. Remember we had all this last week where for about 5 or 6 runs in a row, GFS broke down the cold quickly, before dropping the whole idea.

[swfc]

Find it hard that one or two posters are keen on the westward movement of fridays front ie good news but the actuall gfs synoptics on the run worthless Id be waiting while late tom evening before plumbing for any outcome east or west of any precipitation and also consider commenting on the models reliability in the same post

Edited January 16, 2013 by swfc

[Zenarcher]

NOGAPS 18z agrees with the likes of the ECM and sends the low down South,

[Long haul to mild]

BBC forecast just now had snow in the East on Saturday. However, the ppn would never get that far if GFS18z is correct. Interesting times coming up.

[Jason M]

Lets see what the ensembles bring. Probably have little support.

The precip not getting to the east in any great amounts doesn't surprise me and I guess it won't surprise a lot of the older posters in this thread. Generally in these set ups the Atlantic steams through or the front dies out west. Short term pain might lead to long term gain though.

Jason

[Cloud 10]

Seems the 18z has a fetish for overpowering blocks...

6 days ago..

[pages]

GFS well out of kilter with the UKMO and ECM with position of the block compared to the other two by day 6. And with its recent reliability I think that we should stick with the UKMO and any model that follows this as a realistic guide to the 6 day outlook.

PS I think we have seen this before already this year!!

Ukmo rock steady and with ECM JMA Bom nogaps gem CMA plus the majority of the ensembles support. Gfs on its own when will it back down, I reckon small steps starting on the morning run, will be back in line at T96 by this time tomorrow but showing the Atlantic coming in at 144 yet again this is becoming a common theme

[snowice]

It looks a real struggle here for the precip to get far east.

These westwards corrections historically aren't a surprise and the models often underestimate the block to the east, certainly nerve shredding for those on the peripheries.

Certainly impossible to call where the snow/dry and snow/rain zone will end up. I've been here before many times when I was living in London and it was like pulling teeth to get the snow to get a move on eastwards.

Even upto the day you just never know what will happen and how much precip will be ahead of the front, I think its best to wait for the morning runs to see if this westwards trend continues.

I was giving up hope till i saw the gfs,ill have a sleepless night

Edited January 16, 2013 by snowice

[nick sussex]

I was giving up hope till i saw the gfs,ill have a sleepness night

It's a shame we can't just find a set up that delivers for everyone. It's very rare to get a countrywide snow event , yes I can imagine there will be sleepness nights for many waiting for the verdict re where the snow will end up.

If I was mad and wanted to be run out of town I'd put a map up showing the snow areas with margin for error. As it is I'll keep quiet and wait for the morning model output!

[pages]

Is anyone really watching the 18z? I have a feeling no one believes the 06z and 18z gfs runs to the extent they are treated like nogaps!

The no gaps has been more consistent this week. Gfs all over the place can't wait to see the verification stats after this spell the wouldn't be surprised to see the gfs below the CMA and nogaps