Model Output Discussion

[Weather-history]

A straw to clutch at and I mean a straw, it looks to me that the 120hr FAX chart is a modification of the 120hr 12z UKMO chart. The low appears to me about 10 degrees in longitude further west on the FAX chart than with the UKMO 120hr 12z chart.

http://www.wetterzentrale.de/pics/Rukm1201.gif

http://www.wetterzentrale.de/pics/brack4.gif

Edited January 30, 2010 by Mr_Data

[andymusic]

is that huge low in the atlantic to blame for all this ?

and lower heights to our north

[snowking]

From the previous thread, I would like to know how the FAX charts can be classified as an outlier?? I've heard some things in my time, but I have never heard of the FAX charts being called an outlier! The FAX charts have human input, and not just any old input, but input from professionals at the Met Office. They have looked at all the data and have gone with what they think is the likely outcome. They don't go and draw up an "outlier"!! In any case, I bet it wouldn't have been called an outlier if it was showing a cold easterly!

:lol:

Brilliant!

I know Ian F said he hoped to see more of a sense of humour in this thread (something I can only echo) but im not sure if this is what he had in mind

I'm not entirely sure i'd like to call anything beyond 48-72 hours at the moment, and its no co-incidence that TV forecasts at the moment reflect that mentality too

As for the ensembles I dont think we really get much from the 18z, and i tend to agree with Ian B that we need the 0z's before jumping to any conclusions. If it were simply an upward trend in temperature at various heights then I would say game over, but with the 18z operational at the very top of the range, whilst the control goes to the very bottom of the range (and with far too much divergence from even day 4) theres just no credibility at the moment in mid-range NWP forecasting. Im sure the guys down at exeter would reflect similarly on the current output

Same applies to the ECMWF with a big split in the solutions from the 12z around the average line

http://www.meteogroup.co.uk/uk/home/weather/services/ensemble_forecast.html

SK

[davehsug]

What was it the Mod asked for at the top of the thread?

This forum's actually OK when there's not an easterly about, but when it is, boy, it's just too painful for words.

Less personal justification, more model chat please...

Actually, that's one of the most pertinent posts I've ever read! I'd never really thought about it & thought it was just cold, but it IS Easterlies!

Such a different place in summer, (until late August when the first bit of blue appears over Greenland!).

Anyhoo back on topic, I honestly don't see any way back from here. Just the slightest chance at the t120/t144 timeframe if the LP is slightly further west & south. Another great disapointment for cold lovers looks probable. I suppose it's not over 'til the fat lady sings...but she's clearing her throat :lol:

[nick sussex]

Yes I noticed this too Nick, I'm sure the 0zs will sort it out given how close this is, obviously it's potentially disappointing for cold fans as if the UKMO is right, I don't feel there is a way back from there, it would be mid-Feb at least before we could see another pattern shift.

Yes I agree Ian, if the UKMO verifies then its a long haul back to cold from there. Whats a little strange this evening is indeed the fax charts, if the UKMO didn't modify them last night when there was even less support for their model, then why choose to modify them this evening when the ECM has trended towards their raw output.

[Bobby]

Who wins? Simples, nobody knows yet.

About it sums it up.

I do feel though that the Beast from the East is like a boxer getting battered in the ring, he's bloodied, tired and getting a good hammering from Mr Atlantic. Could still pull something out of nowhere, stage a great comeback and win the fight... but... you wouldn't bet on it..

Edited January 30, 2010 by Barb-

[karyo]

Yes I agree Ian, if the UKMO verifies then its a long haul back to cold from there. Whats a little strange this evening is indeed the fax charts, if the UKMO didn't modify them last night when there was even less support for their model, then why choose to modify them this evening when the ECM has trended towards their raw output.

Probably because a different forecaster did them tonight!

Karyo

[kumquat]

Clearly now they feel that with the ECM (operational) on board they have the confidence to back their own model,

There have been a few hilarious insights into the Exeter modus operandi recently.

On holiday in St Ives (SW) and had a few hairy showers to deal with over Bodmin today. Not long-lasting but incredible white-outs. You could go 1 mile down the A30 from sunny cold skies to suddenly hitting an ich of slush where the last blizzard burst hit. Or hail to fat flakes and suddenly the green hillside ahead that you saw ten minutes before was totally white.

I'm kind of hanging in there with the gfs 18z. Simply because this winter has been very different - and I've not seen snow in Cornwall before, but I'm ecstatic that I did today. In fact, I think the GFS is on the backtrack. Its going to show what it did 4/5 days ago tomorrow. The Beast. And watch the ECM / UKMO follow suit.

[Cecil Hogmanay Melchett]

Looking at the ensembles for gfs AND ecm it appears there is still a stand off between a group pushing the Lows

SE and the a slightly bigger group pushing the Atlantic right through us.

While i agree things are weighted against the Easterly at this juncture i wouldnt rule out an entirely better

outlook come the 0z runs.The pros seem to think the euros have the correct handle on this but we still just about have time on our side for one more twist.

I'll wait until 0z runs before giving up.

:lol:

[TEITS]

How ironic the 18Z ensembles in the short term are a massive upgrade compared to what I have seen in recent runs. The mean almost drops to -10C before a rise to -5C.

http://charts.netweather.tv/ensimages/ens.20100130/18/t850Cambridgeshire.png

Im sitting on the fence still at the moment. If you were using past experience as a forecast then you would say the UKMO/ECM are correct at +144 and the GFS/ensembles will slowly trend towards the Ops. However I then remind myself that I have seen sudden changes in the model output back towards a cold pattern with last Dec being an example and also Dec 05 E,ly.

One more comment I will add is I sometimes wonder about the fax charts. Remember only recently the fax chart backed an E,ly and this is why the BBC forecasts suggested sub zero temps and snow. However many of us couldn't understand the logic behind the fax chart as it seemed likely the UKMO would backtrack towards the ECM/GFS. This is exactly what occured which led some members to believe the BBC/Met O had a secret model. My point is these fax charts can change along with the model output. Remember we're still looking at the +96/+120 timeframe and trust me when I say this can change.

I bet if you had a discussion with a Met O forecaster they wouldn't be convinced of the model output beyond +96.

[karyo]

Looking at the ensembles for gfs AND ecm it appears there is still a stand off between a group pushing the Lows

SE and the a slightly bigger group pushing the Atlantic right through us.

While i agree things are weighted against the Easterly at this juncture i wouldnt rule out an entirely better

outlook come the 0z runs.The pros seem to think the euros have the correct handle on this but we still just about have time on our side for one more twist.

I'll wait until 0z runs before giving up.

:lol:

Be prepared to give up though to avoid further disappointment! That's what I do anyway.

Massive turnaround in the last 24 hours!

Karyo

[La Bise]

Has the in-between, slack se flow solution completely gone then?

[TEITS]

Has the in-between, slack se flow solution completely gone then?

I never agreed to the in=between solution in the first place.

This is very much either the Atlantic wins and we see mild SW,lys Or we see LP going under the block bringing a cold SE,ly with this eventually backing E,ly.

Another comment I will make although some will call this hopecasting but frankly I don't care. In these situations I often find at +144 the models are always progressive when it comes to the atlantic vs blocking and are very reluctant to show shortwaves splitting from the LP and going under the block. What sometimes happens is it isn't until +72 that the models show this. So whilst the atlantic SW,lys look favourite do not be surprised if we see the models back towards what I suggest at +72. I really don't think we have seen the end of the drama just yet!

[Cheese Rice]

Has the in-between, slack se flow solution completely gone then?

No one knows, after Tuesday it's anyones guess.

I never agreed to the in=between solution in the first place.

This is very much either the Atlantic wins and we see mild SW,lys Or we see LP going under the block bringing a cold SE,ly with this eventually backing E,ly.

Another comment I will make although some will call this hopecasting but frankly I don't care. In these situations I often find at +144 the models are always progressive when it comes to the atlantic vs blocking and are very reluctant to show shortwaves splitting from the LP and going under the block. What sometimes happens is it isn't until +72 that the models show this. So whilst the atlantic SW,lys look favourite do not be surprised if we see the models back towards what I suggest at +72. I really don't think we have seen the end of the drama just yet!

Agree, I remember last week (?) the GFS underestimated the block to our east, this could easily happen again.

[kumquat]

Daily data input (from over the E Europe snowfields) have skewed the ECM output which gloriously overblows the block to the point where it implodes. If its not right going in - its a goner on the way out.

[billy]

I never agreed to the in=between solution in the first place.

This is very much either the Atlantic wins and we see mild SW,lys Or we see LP going under the block bringing a cold SE,ly with this eventually backing E,ly.

Another comment I will make although some will call this hopecasting but frankly I don't care. In these situations I often find at +144 the models are always progressive when it comes to the atlantic vs blocking and are very reluctant to show shortwaves splitting from the LP and going under the block. What sometimes happens is it isn't until +72 that the models show this. So whilst the atlantic SW,lys look favourite do not be surprised if we see the models back towards what I suggest at +72. I really don't think we have seen the end of the drama just yet!

And it may just be me ,but do you think the ecm has been very erratic since its upgrade ? Or is it just another straw to clutch

[Tom D]

Daily data input (from over the E Europe snowfields) have skewed the ECM output which gloriously overblows the block to the point where it implodes. If its not right going in - its a goner on the way out.

Where's your source and what does that actually mean?

[LomondSnowstorm]

I never agreed to the in=between solution in the first place.

This is very much either the Atlantic wins and we see mild SW,lys Or we see LP going under the block bringing a cold SE,ly with this eventually backing E,ly.

Another comment I will make although some will call this hopecasting but frankly I don't care. In these situations I often find at +144 the models are always progressive when it comes to the atlantic vs blocking and are very reluctant to show shortwaves splitting from the LP and going under the block. What sometimes happens is it isn't until +72 that the models show this. So whilst the atlantic SW,lys look favourite do not be surprised if we see the models back towards what I suggest at +72. I really don't think we have seen the end of the drama just yet!

Agreed, shortwaves tend to go under the radar for a bit, and maybe it's just me but I find that the UKMO doesn't handle shortwaves very well, but perhaps that is just me looking for what I want to see! It's a very exciting situation though, one which most people thought would be resolved today but hasn't been. The 00Zs are going to make for interesting viewing indeed, but my advice is to expect the UKMO solution to be adopted by all the models, not because that's necessarily what will happen, but expecting anything more is setting yourself up for disappointment with no real reason for assuming the models tomorrow will back the easterly. Perhaps this is just my dour east coast Scot culturally-Calvinist attitude kicking in but expecting low is the way to go in this situation IMHO!

LS

[Tom D]

Agreed, shortwaves tend to go under the radar for a bit, and maybe it's just me but I find that the UKMO doesn't handle shortwaves very well, but perhaps that is just me looking for what I want to see! It's a very exciting situation though, one which most people thought would be resolved today but hasn't been. The 00Zs are going to make for interesting viewing indeed, but my advice is to expect the UKMO solution to be adopted by all the models, not because that's necessarily what will happen, but expecting anything more is setting yourself up for disappointment with no real reason for assuming the models tomorrow will back the easterly. Perhaps this is just my dour east coast Scot culturally-Calvinist attitude kicking in but expecting low is the way to go in this situation IMHO!

LS

Correct me if I'm wrong but before Christmas I'm sure there was an event where a shortwave formed off the east coast of England and moved right across the southeast section of the UK giving some decent snowfall for many - something the GFS did not pick up on at all, even up until the last minute, whereas the UKMO did pick it up, IIRC.

Edited January 31, 2010 by Tommyd1258

[TEITS]

And it may just be me ,but do you think the ecm has been very erratic since its upgrade ? Or is it just another straw to clutch

Actually yes is the answer.

So far we have seen Feb 1947, couple of cold SE,lys, A few cold E,lys, BBQ S,lys and this has been over the last 3-4 days!

Never been a fan of the ECM +192/216/240 charts which is why for this timeframe I use the GEFS/GEM means.

I don't want members thinking that im dismissing the UKMO/ECM because that would be wrong of me. However I have little faith in any of the model output at the moment and they could all be wrong.

Look at these ensembles for Aberdeen.

http://charts.netweather.tv/ensimages/ens.20100130/18/t850Aberdeenshire.png

These are frankly stunning and if we didn't have access to the UKMO/ECM this forum would be in meltdown with all the ramping.

Agreed, shortwaves tend to go under the radar for a bit, and maybe it's just me but I find that the UKMO doesn't handle shortwaves very well, but perhaps that is just me looking for what I want to see! It's a very exciting situation though, one which most people thought would be resolved today but hasn't been. The 00Zs are going to make for interesting viewing indeed, but my advice is to expect the UKMO solution to be adopted by all the models, not because that's necessarily what will happen, but expecting anything more is setting yourself up for disappointment with no real reason for assuming the models tomorrow will back the easterly. Perhaps this is just my dour east coast Scot culturally-Calvinist attitude kicking in but expecting low is the way to go in this situation IMHO!

LS

Very wise words and exactly the right attitude to have IMO.

Edited January 31, 2010 by THE EYE IN THE SKY

[billy]

Actually yes is the answer.

So far we have seen Feb 1947, couple of cold SE,lys, A few cold E,lys, BBQ S,lys and this has been over the last 3-4 days!

Never been a fan of the ECM +192/216/240 charts which is why for this timeframe I use the GEFS/GEM means.

I don't want members thinking that im dismissing the UKMO/ECM because that would be wrong of me. However I have little faith in any of the model output at the moment and they could all be wrong.

Look at these ensembles for Aberdeen.

http://charts.netwea...erdeenshire.png

These are frankly stunning and if we didn't have access to the UKMO/ECM this forum would be in meltdown with all the ramping.

And the GFS has been very consistent in the past week or so. Rob Mcelwee just said milder this week , then said well at least for half of the country. But he didnt elaborate any further. Interesting

[LomondSnowstorm]

Correct me if I'm wrong but before Christmas I'm sure there was an event where a shortwave formed off the east coast of England and moved right across the southeast section of the UK giving some decent snowfall for many - something the GFS did not pick up on at all, even up until the last minute, whereas the UKMO did pick it up, IIRC.

I'm sure that happened, as it fits fairly well with the overall pattern of the trough sitting over the UK. The event I remember was the 23rd December though, when a shortwave brought 5 inches of snow here, something picked up by the GFS and NMM but not at all by the beeb, who were still calling dry as snow was falling - I don't think any model is that good at picking them up, though I always thought that the GFS tended to overdo them (perhaps the old op specifically) while the UKMO didn't pick them up as well. Either way, shortwaves will chop and change as usual and in this instance could be key to the overall pattern.

[kumquat]

Steve Murr's post was telling tonight. Event alert for the South and West Tuesday/ Weds

[Tom D]

I'm sure that happened, as it fits fairly well with the overall pattern of the trough sitting over the UK. The event I remember was the 23rd December though, when a shortwave brought 5 inches of snow here, something picked up by the GFS and NMM but not at all by the beeb, who were still calling dry as snow was falling - I don't think any model is that good at picking them up, though I always thought that the GFS tended to overdo them (perhaps the old op specifically) while the UKMO didn't pick them up as well. Either way, shortwaves will chop and change as usual and in this instance could be key to the overall pattern.

Ah OK, thanks for the correction. Will see what's happening in the morning then after the Aussie final

[TEITS]

And the GFS has been very consistent in the past week or so. Rob Mcelwee just said milder this week , then said well at least for half of the country. But he didnt elaborate any further. Interesting

Difficult to judge because I don't know if hes referring to the whole of next week or only part of it.

Based on the fax charts we see a warm front pushing SE on Monday night followed by a cold front moving S during Tues.

http://www.wetterzentrale.de/pics/brack2.gif

Wednesday looks a chilly day at the moment. We then see milder SW,lys spreading across the whole of the country during Thursday.

http://www.wetterzentrale.de/pics/brack4.gif

However GFS disagrees with Thurs because we have cold SE,lys!

http://www.wetterzentrale.de/pics/Rtavn12017.png

All of the above is subject to change especially Thurs onwards.