Model Output Discussion - 14th - 20th November

[reef]

A new thread for the new week to discuss the models.

The previous thread was full of bickering and personal comments. If you feel a post is against the rules, we'd appreciate if you'd use the report function rather than mention it in the thread.

Please continue..

[scotty_boy_winter]

I still believe background Synoptics are going to leave this winter very frustrating. The strengthening polar vortex is going to finish off November and the majority of not all of December. The talk from today's met office boffo according to my uncle is that December will be +nao +ao dominated as I got slated for giving a heads up on 3 - 4 weeks ago. This place will be depressing for hopecasters this winter I feel...let's enjoy the Atlantic depressions. It's better to just enjoy what's in front of us rather than chasing phantom snow that will not happen

[Harve]

While not an unrealistically cold FI in itself, it is rather implausible as a Greenland high of 1075mb develops seemingly out of nowhere with little support from teleconnections (though I'm certainly no expert on these). Does anyone know what Greenland's highest pressure recorded in last November / December's spell was?

Of course it will not verify, but I'm curious as to why the GFS decided to forecast such crazy pressure rises in the Arctic, or is this it's usual behaviour? It's certainly an abrupt change and we can only assume it will be back to the usual Euro-high next run.

And the pressure gradient from Greenland to Norway is mental too! If only...

Edited November 14, 2011 by Harve

[Dave Kightley_12837]

very progressive but nice to see. i dnt know how it came to that so quickly though. just shows how much confusion there is ahead though. nothing clear as of that

[Cecil Hogmanay Melchett]

^{Well at last} GFS ^{offers some eye candy to the cold weather fans in the UK,only caveat being its far flung f1 and has about a 2% chance of veryifying.}

^{One thing is for sure though i really hope it DOES happen as that would be a classic polar north west wind and would produce the goods big time for NW Britain. :wub:}

^{All comes about due to an intense high out of the canadian arctic.}

^{The rest of the run before it is dreadful though.}

[Great Plum]

Whilst deep FI does look like an implausible option, check the ensembles: http://www.netweather.tv/index.cgi?action=charts;type=ens;sess=

It is not an outlier... Interesting!

[rich1]

Whilst deep FI does look like an implausible option, check the ensembles: http://www.netweathe...;type=ens;sess=

It is not an outlier... Interesting!

Its more for academic purposes at that range but at least its better than relentless mild all the way through the suite

guess December is still 2 weeks away and for me thats the time to look for for when things perhaps might more interesting in terms of colder conditions. Still a long way off in terms of knowing what things will be like but knowing these patterns, would be very suprised so see anything cold before the end of this month. After all, 2009 saw no notable cold before the middle of december, perhaps it could be similar this year too, if it is, can live with this kind of set up for a few weeks more

[Rocheydub]

If that GFS were to transpire, I'd eat my sizeable hat! A very implausible outcome. In my opinion of course

[VillagePlank]

Here's this morning's GEFS 850hPa analysis,

Pretty nondescript, really; a gentle descent into winter, proper. Undoubtedly, the bias for this set of runs is on the cold, at some points by a degree or two. But when I say cold, I mean, not that cold.

Any hope? Yes - the trend for the maximum temperature of the run is hardly positive now, the minimum temperature run is significantly negative, and mean is gently negative. This means some important (less warm!) scenarios are now being computed - whether they turn into fruition is another thing.

Edited November 14, 2011 by Boar Wrinklestorm

[Dave Kightley_12837]

not a bad ecm 240z either. showing blocking of sorts on both gfs and ecm. better runs this morning. (better then ecm 12z 240 anyway)

Edited November 14, 2011 by Dave Kightley_12837

[mountain shadow]

After yesterdays model horror story for coldies it's good to see both GFS and ECM try and bring in some much colder weather. The GFS ensembles are most encouraging.

Edited November 14, 2011 by mountain shadow

[Liam J]

Better 00z run on the ECM this morning, but still some differences between models regarding pressure distribution. ECM shows a block to the NE resulting in an easterly wind, whilst GFS & GEM show a more unsettled picture with high pressure centered further south and west with a tight pressure gradients at times as depressions move over Northern Britain, JMA also in with the latter two.

GFS ends wintry with a large depression over the UK feeding in N/NEwinds from Scandinavia. It looks like the Atlantic will crash over Northern and Central Britain, but where we go after here is still not clear yet.

Edited November 14, 2011 by Liam J

[weather_it_will]

Looking at the 00Z GFS ensembles, anything much beyond T120 is not reliable where the air pressure could change either way.

[JCP]

The GFS ensembles are most encouraging.

Well, the mean is above average from start to finish, what is encouraging about that?

For my money, ECM is on to something - it's been sniffing around the idea of a more blocked outlook for sometime and just won't give up on it!

[cold snap]

good morning all,at least some give this morning in both gfs ecm but its way out in fanstasy island for what the gfs shows.to be honest it good to see a different situation may be gone on the 6z

[Liam J]

For my money, ECM is on to something - it's been sniffing around the idea of a more blocked outlook for sometime and just won't give up on it!

You could say the same of the GFS and also a few other models, they haven't given up with showing the Atlantic coming into play for a period of time, ECM seems on it's own here with the blocking positioning. GEFS emsemble run also supports a more mobile picture, ECM has it's own ideas regarding the Atlantic and goes against other models and their outputs.

Edited November 14, 2011 by Liam J

[Dave Kightley]

You could say the same of the GFS and also a few other models, they haven't given up with showing the Atlantic coming into play for a period of time, ECM seems on it's own here with the blocking positioning.

Blocking at the end of the run? so diffrent then the ecm though. all to play for

[rich1]

Well, the mean is above average from start to finish, what is encouraging about that?

For my money, ECM is on to something - it's been sniffing around the idea of a more blocked outlook for sometime and just won't give up on it!

Guess its all relative, having an op run with an intense Greenland high at the end which isnt entirely unsupported at the fag end of the range makes a change. Cant really remember any sort of cold weather appearing in the GFS ops for weeks. personally i prefer that solution to the ECM which resembles in that form a displacement of the Euro bloc further north with less cold air about, though its probably fair to say the ECM on pattern evidence may be a bit more likely. Both are a improvement of kinds mind

but at this time, its all way in the future, but it looks slightly less grim seeing those going in to December than a day or two ago. It will probably switch back soon but the key with these things is to see whether they appear in the outputs again in the next few days. if they do then maybe something could be afoot

its not 'great' but guess we have to start somewhere

[wolvesfan]

Morning all,

Interesting models this morning,GFS stalling the atlantic further from yesterdays runs,the jet tracking further NE over the top then completes the run with high pressure being sucked up into greenland.ECM gives us a scandi high by around t192 and undercuts with some energy from the jet to finsh,this propbably best for any cold lovers.big diffrences then from ECM,GFS regarding the scandi high,i did think yesterday GFS was a little hasty in flattening pressure to our east,it will be interesting to see what happens in the upcoming runs.

[snowfall09]

Could anyone point me in the right direction to the AO and NAO data

[No Balls Like Snow Balls]

Wow the ECM is a turn up for the books, wasn't expecting that. The whole process that the ECM end's up with starts the process at T144 which is probably just after the reliable at the moment. While the op run is at the colder end of the ensembles it's not a outlier. Shame the GFS is not similar at T144 and shows the Atlantic much closer and the euro high much further South, so you would have to say the ECM looks unlikely to happen but not impossible.

[shedhead]

Could anyone point me in the right direction to the AO and NAO data

Here you go.... http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/mjo.shtml

[snowfall09]

Here you go.... http://www.cpc.ncep....k/MJO/mjo.shtml

Thank you

Edited November 14, 2011 by snowfall09

[BLAST FROM THE PAST]

Lol, models eh? What is of interest is the period 'last week' of Nov as no cold shot is anticipated before then. For me what the models show in FI is just that, FI and even if they conform with my 'idea' I don't trust them yet but end of this week I think we will get a reasonable idea whether it becomes zonal, cold shot or de ja vu. The change in the runs shows that, although at least I suspect some interest will build.

BFTP

[mulzy]

Seems to me that the (mean of the) ECM ensembles show the blocking more to the East/South-East rather than the North-East, so not so good for a "cold" evolution. The ECM operational could be an outlier...

Edited November 14, 2011 by mulzy