Model Output Discussion

[Ben_Cambs]

In typical model fashion the UKMO goes from zero to hero at 120hrs! Looks better than the GFS with a stronger easterly flow.

http://www.meteociel...=120&carte=1021

Yes with that chart Im quite sure Southern and Eastern areas of the UK would see widespread heavy snow showers in that chart, and maybe Central areas too.

Also interesting in the UKMO PPN charts at T+72, showing the trough coming down from the North Sea.

http://www.meteociel.fr/modeles/ukmo2.php?nh=&carte=1594&ech=6

And then we have the right Upper temps to support the snow aswell:

http://www.meteociel.fr/modeles/ukmo2.php?nh=&carte=1007&ech=6

[Iceberg]

Can't believe people are calling this cold off/a damp squid or saying that it keeps getting put back. Well yes I can actually. But the models speak for themselves, below is the latest NAE showing the precip for tomorrow and DP's, 1000-850 thicknesses are good as well.

A fair few people will get a shower or two tomorrow, it won't settle but it a nice little start, mroe snow is still forecasted by METO and GFS for wed/thur and then more at the weekend.

Good MET GM isn't it Nick, GFS isn't bad either.

[Tom D]

There's little need to worry about a high building across the UK - the source air is very cold from Europe and in many way this will cause the cold to become embedded. The potential in the GFS 12z +144 chart tonight it there for cold and as said before this winter - with cold comes snow (eventually), whether it's from troughs or shortwaves which are not forcast or undercutting and frontal snowfall.

It's a set up that will give us another 10-14 days of very cold weather from today.

[Rollo]

In typical model fashion the UKMO goes from zero to hero at 120hrs! Looks better than the GFS with a stronger easterly flow.

http://www.meteociel.fr/modeles/ukmo2.php?nh=&ech=120&carte=1021

I think it was only yesterday that GP said the computors wiuld have great difficulty reading the current patterns and would be all over the place-seems he is right yet again.

[Iceberg]

GFS goes the persistant cold pool across the south again 168-200 as the High retrogresses, so the consistance is good to see.

[Bolton67]

the Gfs 12z has the high further south for about 24hrs before it starts to retrograde, cant really see why people are being so negative on here this afternoon, i think they must have scared everyone off, i thought it would be much busier.

By the way, just had our first shower of the afternoon which was rain witha slight bit of sleetyness mixed in

Yes john it does! @ T+114 TO T+168

we see the flow coming from the east, then North east @ T+174 it becomes more Easterly.

Good run!!

[Cheese Rice]

I dont think the GFS is that good tbh, not as good as everyone is saying. The initial strong easterly flow which we were all expecting on Thursday/Friday has pretty much gone, we do get the -10 air but the area of -10 850's have slowly decreased on each run. So much so that that the -10 850's just about reach Newcastle when they were meant to reach southern Scotland. The airflow doesn't have a cold source, we are relying on a cold pool which will only disappear over time.

Anyway the outlook looks cold and frosty, but not very cold, a couple of degrees below average. Any snow looks to be confined to the south East and the east coast, but even here it could be marginal.

[Eugene]

I`m really liking GFS 12Z, slower retrogression means longer cold spell, bring it on and the high is not slipping south at all.

[Paul]

Final warning for some on here - either abide by the rules of the forum and stick to the topic in hand or we'll have to take further action and stop the worst offenders from posting.

Info on the types of model threads and what should go in which can be found here:

http://forum.netweat...4entry1765454

And just to offer a piece of advice which may stand some in good stead - if you feel your post needs to include lines such as:

Sorry mods this is off topic but...

or

This will be deleted soon, but..

or

I know this is off topic but...

Then don't post it in this thread - post it into somewhere where it won't be off topic!!!

As ever, please don't use this thread to comment on or discuss the above - feel free to pm me or any of the other team members should you wish to ask any questions of give any feedback though.

Thanks

Paul

PS - Thanks to those using the report button on off topic posts etc - it really helps the team out

[Iceni]

As I've posted in the local thread-the problem is most people are looking at charts as they simply show-almost the flat earth idea, no disrespect intended, but the weather is 3 dimensional. Take a look, for your own areas all of you, at the skew-t diagrams.

Some of them will show little sign of 'sunshine and showers' but many down the eastern side will show that-I did a blog I think yesterday to try and help illustrate that idea. Do take a look, and if you are down the eastern side, say Yorks down E Anglia into Kent perhaps, drop in and see the pdf I'm going to post this evening using Doncaster skew-t to try and illustrate this 3 dimensional idea.

Indeed even before then call up the latest sat picc-show the visual in detail over the UK. Look east at that awful Sc/St cloud sheet and tell me if it extends all the way across the N Sea?

John where are these skew-t diagrams? I've got NWLite or are they on the full version?

[londonsnow]

still looks like the serious cold is heading towards austria, n italy, the swiss and the alps/massif. anyway just one gfs run. it'll all change

[Paul]

John where are these skew-t diagrams? I've got NWLite or are they on the full version?

Yes they're in the full extra subscription, but there are a selection out to 96 hours in the free datacentre:

http://www.netweather.tv/index.cgi?action=nwdcskew;sess=

[karyo]

The 12Z UKMO precipitation charts look rather tasty for midweek! Plenty of showers coming over the North sea and moving southwestwards!

http://www.meteociel.fr/modeles/ukmo2.php?nh=&ech=72&carte=1594

Karyo

[Filski]

Curious, GFS continues to prog a risk of snow this evening in the SE. Light precip is shown inside the next 48hrs too. I know it's too warm but it is mizzling out there now. Just how marginal is the snow risk in the early part of the week and will this marginality continue to be a factor leading up to Wed/Thurs. Dew points are too high so why the continued snow risk?

[Eugene]

http://www.wetterzentrale.de/pics/Rtavn3361.png. Fantastic run IMO, as long as the cold spell lasts all February or most of it i`ll be happy, cvouldn't give a damn what happens after March 1st to be honest

[Bolton67]

No complaing from me at that 12z run even at T+180 it still has us in an Easterly

Edited February 7, 2010 by Lancs_Northants

[Eugene]

http://www.wetterzentrale.de/pics/Rtavn3841.png - Incredible end too with no end in sight with a very cold mass of air building up north ready to move south

http://www.wetterzentrale.de/pics/Rtavn3842.png

[karyo]

I`m really liking GFS 12Z, slower retrogression means longer cold spell, bring it on and the high is not slipping south at all.

Yes, a brilliant output! Note how the low pressure around Newfoundland stays stationary there, helping to maintain the block over Greenland and preventing it shifting westwards (west based -NAO).

Karyo

[Iceberg]

Curious, GFS continues to prog a risk of snow this evening in the SE. Light precip is shown inside the next 48hrs too. I know it's too warm but it is mizzling out there now. Just how marginal is the snow risk in the early part of the week and will this marginality continue to be a factor leading up to Wed/Thurs. Dew points are too high so why the continued snow risk?

Filski, see the NAE DP chart for Monday I posted above, I am not sure where this marginality is coming from( not saying it's coming from you), if the precip has any depth to it at all then it will be sleet or snow, this is fully supported by the NAE DP's, 1000-850's, 950 temps etc etc.

Monday will be marginal for some, understandably as the cold air is still getting in, but according to the charts and even the Beeb the marginality quickly fades.

[Ben_Cambs]

A very good GFS 12z if you like cold, no sign from start to end of Atlantic weather. With the high retrogressing North Westwards, especially towards the end of the run it could be a very wintry outlook for the next 2 weeks, like a couple of members have said today.

But much closer to now, on Wednesday we see a trough moving South Westwards. I think tonight we will see the FAX's back the raw output from UKMO.

[Blizzard_of_Oz]

A very slow start and a very slow end to the cold- very cold weather as some 1 already posted on here wasnt it Steve or Nick that told us so ? The models now show us this its incredible if they remain the same because snow would be in there some where so be patient and dont worry.

Edit: God give me strength Im off this forum now.

Edited February 7, 2010 by Blizzard_of_Oz

[Lewis]

After looking at the 12z, I kind of agree with many, as we get closer to the timeframe it's just pushed further and further back, even the easterly that was showing on the 7-8th of this month has now been pushed back to friday and is looking much tamer, if anything nothing other than a cold pool of air.

The high pressure sits there and just fills out.

Other than the odd snow shower, affecting costal areas, day time temps of 4-5c's which is not that cold, and night time severe frosts, it's practially a non-event in terms of severity.

Again, still time for changes. But the way the models just push it further back, and the 850's are getting warmer run by run.

[johnholmes]

John where are these skew-t diagrams? I've got NWLite or are they on the full version?

therare basic ones on basic NW-not sure about lite-need to pm Paul and ask

[SMU]

A very slow start and a very slow end to the cold- very cold weather as some 1 already posted on here wasnt it Steve or Nick that told us so ? The models now show us this its incredible if they remain the same because snow would be in there some where so be patient and dont worry.

yeah it was me-- this is a definite slow burner- I will try & get one of those special long posts up later this eve-

Lewis- 850's getting warmer- their getting colder mate- the mean was only ever down to -10c-

Now we have -13c on tap-

http://www.wetterzentrale.de/pics/Rmgfs1262.gif

S

[Eugene]

lol yes too many assumptions going on as usual and looking at the ensembles shows the very cold air could easily back our way if people think GFS 12Z OP has nailed later in the week exactly then they really have alot to learn.

http://www.meteociel.fr/modeles/gefs_cartes.php?ech=96&code=7&mode=0&runpara=