Model Output Discussion - 23rd Jan - 12z onwards

[EML Network]

I think the clues in the name ?

 

Glad I don't live there, can you imagine how boring it would be.

 

''Today the weather will be the same as it was yesterday and the day before that and every other day before that since this time last year''

 

18z seems to be playing out the same way as it's 12z , amazed at the difference between the center of the low at +96 between the GFS and other models. 

 

Gfs + 96

 

ECM has the center of that low some 500 miles further East at a time frame of just 4 days away !!

 

UKMO even more so, quite remarkable how the GFS is modelling this incoming Low, compared to the other models. 

Is it going to have egg on it's face yet again ?

 

[chionomaniac]

How much was your crystal ball and where can I find one?

 

 

Well the BBC News 24 forecast for the next week just before 10.00pm was about as cold as you can get from Wed onwards.

 

 

SIMPLES! Lol.

 All off topic and add nothing - Come on guys please show some self restraint.

[Ali1977]

I think the weather warnings for Wed/Thurs may extend to Fri looking at the GFS. There looks like a decent trough coming down from the North on Thurs night/Fri morning that may give some snowfall. Not that it means everything but 850s slightly lower for this time period on this run also.

[*Stormforce~beka*]

very marginal, rain low levels?, to newbies, purples do not mean cold

Oh oops - What do the purples mean then? I thought we were all going to die then!!

I was thinking blue was cole enough before but purple thats like artic! lol

 

Educate me ...

[Ice Day]

I like that Ian Ferguson has been largely absent today.  He's often on here keeping our feet on the ground when we're over-hyping cold events, maybe this one's for real?!  Oh, and here's the 132, looking tasty again.

 

[Snowman.]

Lots of interest in a much more reliable time frame. However this is snow so things aren't nailed till even that day or the day before.

 

 

28th 10:00 (3 days away) on the GFS brings in a front that is likely to produce some decent snowfalls over Scotland hills and maybe even to lower levels in west the. Ireland sees some decent snowfalls as well.

 

 

FF 3hrs and snow hasn't let up in Scotland and a band on the leading edge rain slowly turns to snow on the back edge.

 

 

3 more hours and pretty much anywhere bar the South coasts and the SW could see some snow, showers mounting up on the NW facing coasts falling as snow, those in the east and SE are likely to see a bit of everything. However settling snow in the south doesn't look to be much as temps are too high for it to settle only for it to fall as wet snow.

 

 

 

DPs

 

 

TEMPS

 

 

So next Wednesday and Thursday isn't without interest. But still time for changes but many could see snow falling at least, which could be the first time for 23 Months. 

Edited January 25, 2015 by SN0WM4N

[Ali1977]

Wider ridge pushing North at T144, that may increase longevity of the Northerly flow...and more importantly it's further West.

Edited January 25, 2015 by Ali1977

[bluearmy]

the regrouping of the vortex nw of Greenland is now showing at day 10 on the ECM ens, I accept it is highly likely. Given that the extended ECM ens seem to keep getting the fi stuff right I note that the direction of travel post the Azores ridge nudging in appears to be another dropping southeast of the trough to our northwest. I guess what I'm seeing is a potential repeat of the current pattern.

Euro trough followed by the Atlantic ridge sinking se across us and thereafter a return to mobility which evolves into another euro trough. last weeks became a disrupting scenario once the amplification illustrated by gfs to become a weak scandi block transpired. That meant the euro trough became cut off as we saw the unconvincing messy breakdown followed by ..... Well I don't really have to describe the last couple of days and the next few.

If it is to repeat, I wonder if we will see a third evolution of the broadscale pattern.

[goosey007]

GFS 18Z starting to firm up on two possible snow events Wednesday night/ Thursday morning and Thursday night Friday morning. I can see why Mr Ferguson said potentially news worthy towards the end of the week for the west country. Though looking at these charts,(yes know they cannot be taken as it shows exactly) but large areas of UK likely to get a hit with some snow after wednesday at least, although there appears to be western bias initially. But this is just the start of the cold spell! The later frames show low pressure system trying to make inroads over south western regions but just ends flirting with the south coast.....snow in Southampton any one?

[Day 10]

A little more amplification than the 12z

 

[Cloud 10]

The new fax chart for thursday has a series of troughs moving down the country from the North with the 528 dam line already clear of the UK...

 

 

 

 

edit:beaten to it by Captain Shortwave ages ago!

Edited January 25, 2015 by Cloud 10

[Ice Day]

Very deep low to the west of greenland that wasn't there earlier.  Nick Sussex, is this good or bad??

 

 

By the way, still looking great at 186!

[Mark Neal.]

Very deep low to the west of greenland that wasn't there earlier.  Nick Sussex, is this good or bad??

 

 

By the way, still looking great at 186!

Thats a strong northerly flow over the UK, and decent heights to the NW (for once).. So i'd imagine that system wouldn't cause too much problems..

[pages]

the regrouping of the vortex nw of Greenland is now showing at day 10 on the ECM ens, I accept it is highly likely. Given that the extended ECM ens seem to keep getting the fi stuff right I note that the direction of travel post the Azores ridge nudging in appears to be another dropping southeast of the trough to our northwest. I guess what I'm seeing is a potential repeat of the current pattern.

Euro trough followed by the Atlantic ridge sinking se across us and thereafter a return to mobility which evolves into another euro trough. last weeks became a disrupting scenario once the amplification illustrated by gfs to become a weak scandi block transpired. That meant the euro trough became cut off as we saw the unconvincing messy breakdown followed by ..... Well I don't really have to describe the last couple of days and the next few.

If it is to repeat, I wonder if we will see a third evolution of the broadscale pattern.

Haven't a clue where the vortex will end up, but can only see it weakening after next week, the lower strat rapidly warms from 120hr hours onwards

Fully expect the models to begin to show a weakening trop vortex in the next few runs. tentative signs already there on the 18z

[Ice Day]

At the risk of being 'duffed up' for using the term, the uppers are lower on this run, down to -8's at 210 over the whole country (don's crash helmet and legs it!)

 

[chionomaniac]

Today has been hard work for the moderating team in this thread. There have been numerous off topic, banter and baiting type posts that have required removing, moving and moderating. This is detracting from the quality of the thread that attracts the members to it in the first place.

 

We don't want to remove the excitement and fun element to the thread but respectively ask for all members to try and ask themselves prior to posting - is this really appropriate and going to benefit the thread - self moderation in a community is what works best. ( Remember if your post has the words 'I know this is off topic but' then delete it yourself and save us the bother!)

 

We have had to put a number of members on restrictions today, so please make sure that you don't add yourself to that list - because those who repeatedly ignore the wishes of the community, will find themselves under restrictions too and will too find themselves unable to post....

 

Thanks

[inghams85]

At 240 the uppers of -8 are still over a large swathe of the country and the azo res is starting edge towards the Greenland locale again. The models great for the North not so great for the South hence a lack of posts lol

[The Enforcer]

Whilst SK was posting, I was coincidentally looking at GFS dewpoint data from today until next Wednesday. I use GFS, because that's the only model for which dewpoint data is available on N-W. On the 06z, after 3pm Wednesday, there are ten frames where dewpoints were above freezing in my location (during the course of Saturday and Sunday). On the 12z, this had dropped to one frame on Sunday. So in this respect, the 12z is better than the 06z. Unable to compare with UKMO or ECM, but assume those will be better as flow source is supposed to be colder.

18z only has two +0 dewpoints for here - both 3pms (Thurs and Fri).

[Ice Day]

At 240 the uppers of -8 are still over a large swathe of the country and the azo res is starting edge towards the Greenland locale again. The models great for the North not so great for the South hence a lack of posts lol

 

Oh I disagree, I'm more than happy with what's on offer tonight.  Plenty of chances over the next 7-10 days I would wager.

[Argyle1980]

Looking better with a good bit of ridging in to Scandinavia and maybe a link with the Russian block!

That's a no for now!

Edited January 25, 2015 by Argyle1980

[West is Best]

Very deep low to the west of greenland that wasn't there earlier.  Nick Sussex, is this good or bad??

 

 

By the way, still looking great at 186!

As I mentioned earlier the jet is belting out of the eastern seaboard and it's not particularly amplified so it's bound to cause cyclogenesis like this. In the absence of upstream blocking I can't see at the moment how the northerly is going to be other than transient, and it may also get shunted further east the closer we get for the same reasons. We need a block.

[TEITS]

I continue to be rather cautious with regards to this oncoming cold spell and shall await the Wed/Thurs/Fri snowfall potential to come into range on the Euro4. Synoptically speaking the model output doesn't exactly excite me very much  The relatively tame N,ly appears to be toppled in the medium range around +240 as high pressure will become either centred over the UK or to our SW.

 

What is disappointing is the ECM ensemble mean suggests the PV will regroup over Greenland.

 

http://www.meteociel.fr/modeles/ecmwf/runs/2015012512/EDH1-240.GIF?25-0

 

Just to put things into perspective but the chart below is what I would call a screaming N,ly. I wasn't born but according to my mother this produced an amazing snowfall in Peterborough via a polar low.

 

http://www.wetterzentrale.de/pics/archive/ra/1969/Rrea00119690208.gif

http://www.wetterzentrale.de/pics/archive/ra/1969/Rrea00219690208.gif

[Mark Neal.]

At 240 the uppers of -8 are still over a large swathe of the country and the azo res is starting edge towards the Greenland locale again. The models great for the North not so great for the South hence a lack of posts lol

Agree with your first point, but yes Northern areas are likely to be closer to the colder temperatures/less marginal sectors as a rule of thumb, us down south think always know there is the risk of being marginal or wrong side. Looking at the output even for down south, snow-madden isn't being forecast but still a cold spell is going to occur, who knows what troughs and disturbances will pop up, some will get surprises, certainly not downbeat down here thats for sure. Looks like the majority are in with a shot of seeing wintry weather!

[inghams85]

I agree! I think as a forum this is being heavily under played. With the thicknesses shown and the length of time the country is over them all sorts or troughs/disturbances/short waves can and probably will prop up. I think the newsworthy side of this spell really could be snowfall with a bit of luck. North West Europe looks like a snow making machine. People are right to be cautious but I forsee several last minute warnings from the Met

[geordiekev]

 

We have had to put a number of members on restrictions today...

 

I thought I had not seen fergie about today, too many ramps in one 24 hour period possibly.

Only jesting and as always pat on the back to the Mods for all their hard work. Personally I think many like myself are suffering model fatigue, but strangely always seems to happen on a Sunday.

I think many would benefit from a break if I'm honest as I think the latest spell , even though within the semi reliable, is going to be a nowcast much like last weekend. So hang on to your hats folks and remember to play fair