Model Output Discussion - 05/01/2016 18z onwards

[chrisbell-nottheweatherman]

6 minutes ago, Jimmyh said:

mild ramping, don't actually see in any of the outlooks post 10 days of anything like a warm up.....

 

 

Even I know that this indicates a warm SWerly flow.  How wet it might be I wouldn't like to say - perhaps drier than the central European high set-up of December, though maybe not for those already affected in the north-west.

[tight isobar]

@shuga ice.

Thats a very direct/assured "forecast"... it's either deliberate mild ramping (for which this is the wrong thread)

Or you have access' to an individual model that even the met are unaware of....?!

[chrisbell-nottheweatherman]

2 hours ago, tight isobar said:

@shuga ice.

Thats a very direct/assured "forecast"... it's either deliberate mild ramping (for which this is the wrong thread)

Or you have access' to an individual model that even the met are unaware of....?!

It is supported by model output - see the following:

 

EDIT for posterity - I posted this while attempting to be more bullish and of a mildie disposition.  If I'm honst, I used a framethat had beenposted on the ramps thread which, I suspect, was chosen as an example of an outlier.

Edited January 8, 2016 by chrisbell-nottheweatherman
I was being a Tutk when I made the original post.

[Nick F]

Worth noting that there are quite high levels of standard deviation surrounding the 'Azores' low approaching from the SW later next week according to the 00z EC ens. The brighter purples/magenta on the 00z high res chart on the right, below, for t192 indicates low confidence in the mslp in the area of that low. Like wise the MSLP ENS mean suggests lower confidence to the SW than to the NW, N and NE ...

So don't think it's all downhill and quickly back into mild SWerlies after next week ...

 

Edited January 8, 2016 by Nick F

[Jimmyh]

22 minutes ago, Shuga ice said:

It will turn colder next week but by no means a very cold or prolonged spell.  I would call it a cool dry spell with wintry showers, mainly on coasts and hills.

it will be warming up again the following week.

Firstly Shuga Ice that is not strictly true when you have cold uppers coming in at

 

7 minutes ago, chrisbell-nottheweatherman said:

It is supported by model output - see the following:

it seems to get through the block incredibly quickly when you look at this

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=192&mode=0

 

 

[phil nw.]

Ok all let's keep it friendly and those who make throwaway statements should back up posts with model output.

I think Nick F in his post above shows there is plenty of uncertainty beyond the next week or so.Brash forecasts in this situation are definitley unwise to say the least.

Back on topic then.

Thanks.

[tight isobar]

10 minutes ago, chrisbell-nottheweatherman said:

It is supported by model output - see the following:

That chart (on an Individual run).Is afull 8days away.

And given the curent model misconduct...Its not worth shaking a stick at...IMO.

[Timmytour]

19 hours ago, Frosty. said:

 

The most frustrating thing with the models at the moment is trying to remove a quote that you intended to replying to the night before but changed your mind, from a post you want to make now!!!!!

Worth remembering for anyone worrying when they read someone say that the models are bringing in an end to a cold spell in eight days time that eight days ago they weren't showing us a cold snap! 

[i luv snow]

3 minutes ago, Timmytour said:

Worth remembering for anyone worrying when they read someone say that the models are bringing in an end to a cold spell in eight days time that eight days ago they weren't showing us a cold snap! 

And also, that with nearly every cold spell which arrives on these shores, models consiistently show an end to it before it actually happens, underestimating how hard it is to shift the cold. So with both these points in mind, bah humbug to the nay-sayers. Particularly those who clearly just try to wind-up others, luckily only one or two. There will be many changes yet! All exciting times though...

Edited January 8, 2016 by i luv snow

[ALL ABOARD]

8 minutes ago, Timmytour said:

The most frustrating thing with the models at the moment is trying to remove a quote that you intended to replying to the night before but changed your mind, from a post you want to make now!!!!!

Worth remembering for anyone worrying when they read someone say that the models are bringing in an end to a cold spell in eight days time that eight days ago they weren't showing us a cold snap! 

Hello, If you hold 'CTRL' and right click on the quote it gives you the option to remove it  hope this helps!

 

 

Edited January 8, 2016 by ALL ABOARD

[SMU]

Last one from me before the 12s

whilst we seemingly have 3 areas of activity to worry about in the 120 arena we must remember they are all linked to each other within a system -

the movement of one impacts the others

Therefor the jet profile I highlighted earlier & whether it lifts out of western greenland quicky or produces a cut off low then snowballs on the angle of the jet in the atlantic at 144-

If we get what the UKMO says with no residual energy & it all lifting out the high pressure can rapidly fill in situ - the net forcing then is energy from the pole moving south towards the UK bringing the very cold air, but also the higher pressure in the atlantic will steer any icelandic shortwave SSE & the subtropical low ENE - missing the UK to the south 

if there is more residual energy driven SSE into SW greenland at 120 producing a closed low then the atlantic ridging is weak with the net energy unable to drive the icelandic shortwave south- also giving little or no resistence North to the subtropical low -

so all eyes on the 12s should be in that area - treat it like a sliding scale - 

more energy out & up NE like UKMO then cold uk

more energy SSE & an area of low pressure = short cold for UK mild SW winds to ensue as subtropical low heads towards scotland-

Middle ground is cold for slightly longer but same result as the above point - mild from the SW soon after - around day 10 - taking us mild from 17th Jan ish...

we must have NO energy then which is why the UKMO worries me slightly as its grid may be missing that energy in situ that the GfS has spotted ....

s

[Alexis]

11 minutes ago, tight isobar said:

That chart (on an Individual run).Is afull 8days away.

And given the curent model misconduct...Its not worth shaking a stick at...IMO.

...and it's an outlier. Check out the ensembles.

[phil nw.]

Talking about uncertainty here's the ens for London from both models

around next weekend appears to be when a big split occurs in the members.

Cold through next week then that low approaching from the sw and it's track and development seem key to future developments.Encouraging to see a fair clutch of cold ens after that though.

 

[legritter]

3 minutes ago, i luv snow said:

And also, that with nearly every cold spell which arrives on these shores, models consiistently show an end to it before it actually happens, underestimating how hard it is to shift the cold. So with both these points in mind, bah humbug to the nay-sayers. Particularly those who clearly just try to wind-up others, luckily only one or two. There will be many changes yet! All exciting times though...

Current charts scream potential, we have a good spell of wintry weather to come synoptics will suddenly appear  and every run of the models will be different ,let's get these cold temp in and then any attack from the Atlantic could produce ,but I think we could be seeing some fun come late Tuesday of next week with features popping up ,let's enjoy it STELLAS all round 

[johnholmes]

58 minutes ago, Howey said:

 

But I'm happy to be corrected!

no correction needed you are pretty much spot on with what the AA and NAO are. 

[carinthian]

8 minutes ago, legritter said:

Current charts scream potential, we have a good spell of wintry weather to come synoptics will suddenly appear  and every run of the models will be different ,let's get these cold temp in and then any attack from the Atlantic could produce ,but I think we could be seeing some fun come late Tuesday of next week with features popping up ,let's enjoy it STELLAS all round 

Sounds good Legritter. Certainly, the UKMO hinting colder in place for 5 days at least next week with a threat of sleet and snow almost anywhere.Thereafter, probabaly in their words the less cold Atlantic weather to win out but maybe not without a battle to dislodge the cold block of Britain. Not all lost yet it ssems.

 C

[Zakos]

1 hour ago, Shuga ice said:

It will turn colder next week but by no means a very cold or prolonged spell.  I would call it a cool dry spell with wintry showers, mainly on coasts and hills.

it will be warming up again the following week.

This is quite contradictory to a post you made last week...

 

The breakdown of the cold weather as shown by the GFS is a possible outcome , but my no means set in stone.

If it were to happen I highly doubt it will be as rapid as the GFS Is showing, I doubt the cold air entrenched over Europe will be swept aside as easily as shown

If we go right out to la la land at 384 hours, we still have a negative AO, both on the 00Z and the 06z.

so even with a potential breakdown this could well be temporary with further cold incursions possible.

[Roger J Smith]

Here's how to get rid of the unwanted quote.

First delete the content of the quote. Then put your cursor back below the quote box with just the person's name in it, and press backspace twice. It's gone, just like the Azores low.

[Barry12]

Don't worry caterpillars, the NASA model is looking good.

 

 

[RachN]

Can I ask a question about the current model outputs and the approaching change, which pretty much everyone agrees is coming, but the disagreements seem to be around, how big a change and how long it stays basically.    What did the models show in the run up to Dec 2010, did they show it coming at least 10 days out, and did they stay on track all the way through, or did they do as they are doing now, and shift/realign/downgrade/upgrade/all agree/all disagree.     I'm just interested as a very very amateur weather watcher, if the models are behaving as you would expect them too?

[ALL ABOARD]

Here's a little sketch to explain in simpler terms about what Steve is speaking about 

This is the ECMWF for 96 hours and 120 hours!

 

We can see that the energy heads south east and its game over from there in terms of long term potential.

Now here's the UKMO for 96hours and 120 hours!

The energy heads north east and allows a more favorable setup to emerge.

p.s ignore the overlay on the ukmo 120 hour chart forgot to delete the previous one.

Edited January 8, 2016 by ALL ABOARD

[nick sussex]

4 minutes ago, RachN said:

Can I ask a question about the current model outputs and the approaching change, which pretty much everyone agrees is coming, but the disagreements seem to be around, how big a change and how long it stays basically.    What did the models show in the run up to Dec 2010, did they show it coming at least 10 days out, and did they stay on track all the way through, or did they do as they are doing now, and shift/realign/downgrade/upgrade/all agree/all disagree.     I'm just interested as a very very amateur weather watcher, if the models are behaving as you would expect them too?

If I remember rightly the December 2010 cold spell had less drama and the models didn't disagree within the T144hrs timeframe.

Normally its easterlies that cause big problems with more divergence in the outputs. Its very unusual to see this type of set up with  disagreements starting within T96 hours.

Edited January 8, 2016 by nick sussex

[johnholmes]

sod it, spent 5 m typing a post and its gone, no idea where, so brief repeat.

Until the output this morning from EC especially, less so GFS, the anomaly charts for at least 3 days had been showing very similar charts for the 6-10 day period. With NOAA also on its 8-14. This morning, see below, EC left the consensus, indeed looking very closely, it had started to do that yesterday. I am not sure if it is the correct idea on things 6 days or more hence or it will come back to the NOAA chart. 2 years ago I would have backed NOAA every time against it but the last 12 months or so and it, sometimes with GFS, has led NOAA to what turns out to be the correct solution for the upper air pattern. This whether it is for the status quo to remain or for a pattern change.

Nor am I sure just how much effect the probable arrival in the North Atlantic of an ex Sub Tropical storm will have. They rarely get picked up correctly by any model for several days as far as position, track and intensity.

We are going to get cold (by definition of that word), indeed the far NE is already so. How much snow for anyone will not be sorted probably until 12-18 hours prior to its prediction. How long the cold lasts is not clear at the moment, at any rate not to me, using the anomaly charts. IF NOAA shows any inclination to follow EC then 4-6 days, if not then perhaps longer. I would not back either way for 1-2 days so enjoy what the weather does for the next week. And hopefully much less will fall from the skies for those folk unable to live or work in their properties.

http://www.cpc.noaa.gov/products/predictions/610day/fxus06.html

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

[cowdog]

6 minutes ago, nick sussex said:

If I remember rightly the December 2010 cold spell had less drama and the models didn't disagree within the T144hrs timeframe.

Normally its easterlies that cause big problems with more divergence in the outputs. Its very unusual to see this type of set up with  disagreements starting within T96 hours.

Might be misremembering but they did chop and change a lot once the cold was shown to appear. Think it switched around 96 hours before a breakdown was expecting to switching to extending the cold, and it was that extension which provided the deepest cold (e.g. when they got almost -18c in Skipton.).

[winterof79]

3 minutes ago, ALL ABOARD said:

Here's a little sketch to explain in simpler terms about what Steve is speaking about 

This is the ECMWF for 96 hours and 120 hours!

 

We can see that the energy heads south east and its game over from there in terms of long term potential.

Now here's the UKMO for 96hours and 120 hours!

The energy heads north east and allows a more favorable setup to emerge.

p.s ignore the overlay on the ukmo 120 hour chart forgot to delete the previous one.

I have splinters in my fingers.The UKMO chart has more of a pronounced greenland ridge on its eastern flank looking at that.The s/e extent of the low toward s/w Greenland looks very similar on both