Model Output Discussion - Autumn 2018

[Interitus]

11 minutes ago, Ed Stone said:

What's the actual number of winters for which the correlation holds, feb? 

Every (supposedly...) from 1976-2012 - correlation 0.91 -

Relive the hysteria - https://www.netweather.tv/forum/topic/81494-october-pattern-index-opi-monitoring-winter-season-2014-2015/

[feb1991blizzard]

@Ed Stone  Read the post by Crewe Cold on this page regarding the death knell.

 

[Methuselah]

Thanks guys.

[Yarmy]

19 minutes ago, Interitus said:

Every (supposedly...) from 1976-2012 - correlation 0.91 -

Relive the hysteria - https://www.netweather.tv/forum/topic/81494-october-pattern-index-opi-monitoring-winter-season-2014-2015/

 

Ha! Notice near the end of the thread (27th Oct), the thread creators introduced (yet) another index - the IZE - produced by a colleague which had a very different outcome. It's kind of described here:

http://www.climatemonitor.it/?p=36712

I've no idea if either of these things are still maintained or have been binned.

[nick sussex]

The OPI had a lot of attention but didn’t amount to much .  And crashed and burned when it promised a colder winter which never materialized .

As everyone knows who follows these forums in winter anything that suggests a colder winter and doesn’t deliver is dispatched to the outer corners of the universe!

 

[Methuselah]

46 minutes ago, nick sussex said:

The OPI had a lot of attention but didn’t amount to much .  And crashed and burned when it promised a colder winter which never materialized .

As everyone knows who follows these forums in winter anything that suggests a colder winter and doesn’t deliver is dispatched to the outer corners of the universe!

 

Indeed...the dice are somewhat loaded? And not in James Madden's favour, either.

[tight isobar]

OPI..INDEX..

please give me strength!.

An in-add, telecon that de-mirrors itself time..and time again!..

9/10 plots/scopes..are irrelevant to the dynamics that are the forcing of such...and direct/now fortunes are the best apply...

I'll chuck up some compares for its 'dire responses'!!!!

Its dog s##t ....for me anyway!

Edited October 4, 2018 by tight isobar

[BlueHedgehog074]

Feel some people may be getting a bit too concerned about what this Winter has in store, especially with it being a while away yet. Despite things such as the OPI index, the SAI index etc, and what they could end up indicating, no one really knows for complete certainty what will happen this Winter.

Also just a friendly reminder to keep things on topic in here please. I know we don’t have a general Winter chat thread released yet (there will be one fairly soon) but would appreciate by ensuring your post isn’t focused just solely on snow and Winter chat, as they’re at risk of getting wiped out, or moved to any suitable threads we currently have, including the regional weather chat threads. Thanks guys and sorry for being a party pooper. It’s just from time to time, like with other threads, we have to defend the Model thread from unsuitable posts!

Edited October 4, 2018 by DiagonalRedLine
Changing last sentence slightly

[blizzard81]

1 hour ago, DiagonalRedLine said:

Feel some people may be getting a bit too concerned about what this Winter has in store, especially with it being a while away yet. Despite things such as the OPI index, the SAI index etc, and what they could end up indicating, no one really knows for complete certainty what will happen this Winter.

Also just a friendly reminder to keep things on topic in here please. I know we don’t have a general Winter chat thread released yet (there will be one fairly soon) but would appreciate by ensuring your post isn’t focused just solely on snow and Winter chat, as they’re at risk of getting wiped out, or moved to any suitable threads we currently have, including the regional weather chat threads. Thanks guys and sorry for being a party pooper. It’s just from time to time, like with other threads, we have to defend the Model thread from unsuitable posts!

Not having a go at anyone but for the sake of a couple more weeks it really would have made sense to keep open the winter thread which was opened this week. I'm pretty sure the above posts would have been posted in that thread had it remained open as opposed to cluttering this thread. Just saying. 

[Mike Poole]

Tonight's UKMO is pretty snappy in aligning the high to give a warm SSE flow as early as T144:

GFS has more of a glancing blow for the warm air later,  here T216:

GEM more generous with the warmth at same time:

It's interesting that the latest Met Office contingency planners forecast gives higher probability to a colder than average October - I think this is now very unlikely given the start to the month and the model output, they also suggested a higher likelihood of a warmer than average 3 month period, I hope that's wrong as well!

Edited October 4, 2018 by Mike Poole

[feb1991blizzard]

If ever there is a run that sums up my weather tastes the 18z CFS from the 3rd of October, Northerlies and Easterlies galore right the way out for 2 months - -8c to -10 engulfing the country even in early April including an insane blizzard in early March for Northern UK.

http://www.meteociel.fr/modeles/cfse_cartes.php?ech=2694&mode=0&carte=1&run=0

[I remember Atlantic 252]

6 minutes ago, feb1991blizzard said:

If ever there is a run that sums up my weather tastes the 18z CFS from the 3rd of October, Northerlies and Easterlies galore right the way out for 2 months - -8c to -10 engulfing the country even in early April including an insane blizzard in early March for Northern UK.

http://www.meteociel.fr/modeles/cfse_cartes.php?ech=2694&mode=0&carte=1&run=0

My Nan's 94th birthday!

[Man With Beard]

That UKMO T144 is a good as it gets for this time of year, won't be far off 25C I reckon if it comes off (and it's not as if the ensembles haven't been threatening it) 

Now - Check this out from the ECM - T192 - central pressure below 950mb!

 

[ICE COLD]

6 minutes ago, Man With Beard said:

That UKMO T144 is a good as it gets for this time of year, won't be far off 25C I reckon if it comes off (and it's not as if the ensembles haven't been threatening it) 

Now - Check this out from the ECM - T192 - central pressure below 950mb!

 

And it moves right over the uk by T216 . 

[ItNeverSnowsInWindsor]

A colder outlook on the gfs 12z!

[feb1991blizzard]

41 minutes ago, prolongedSnowLover said:

A colder outlook on the gfs 12z!

An even colder outlook on the CFS.

[damianslaw]

In the short term - a shift to a cooler outlook as the polar front boundary pivots south through the UK, meaning most away from far south come the weekend, will see quite a marked downturn in temperatures and rain for central parts - some heavy. 

Into next week, back to the southwesterly airstream, murky wet dull conditions for the NW, drier and feeling very pleasant in the south and east. As we move through next week, all eyes on the position of heights to our east, if these are centred more over Germany/Denmark then the atlantic will be held off, and we will stay locked in a very mild southwesterly/southerly airstream with the jet elongated far to the north on a sw-ne trajectory, and we may see a resurgent azores high which will maintain the calmer settled mild period, however, a shift further to the east - as suggested by the ECM this evening and increasingly so the GFS longer term, then the atlantic will have an easy time fighting back, and indeed we could then see generally unsettled conditions for all, possibly cyclonic and increasingly cooler again.

 

[Frosty.]

Really quiet in here..anyway this from the Ecm 12z would certainly blow the cobwebs away...very autumnal indeed!

[feb1991blizzard]

30 minutes ago, Frosty. said:

Really quiet in here..anyway this from the Ecm 12z would certainly blow the cobwebs away...very autumnal indeed!

We could do with some trough disruption in the atlantic with energy going south and the trough elongating negatively tilted, there could be the start of some better ridging to the North of it though, trying to get into Greenland.

[Andy Bown]

58 minutes ago, Frosty. said:

Really quiet in here..anyway this from the Ecm 12z would certainly blow the cobwebs away...very autumnal indeed!

It's quite uncanny how frequently the worst conditions keep occurring at weekends. That would be the 3rd poor Saturday out of 4 (given how bad this Saturday looks and with a fine week in between) , in the amazing summer there were 3 poor Sundays with great days sandwiching them and even on a dry weekend (last weekend) amidst a very pleasant early Autumn spell the coolest, dullest day was Sunday.

Edited October 4, 2018 by Andy Bown

[Newberryone]

Day 10 on the 12z Ecm has an interesting little feature as well down to the south west. Could that Hollywood wind machine be about to roll into town again. Then again, all very dependent on those heights to the east as to whether this has the potential to develop further or not.

[mb018538]

ECM, GEM and GFS all favouring the high pressure winning out (next weekend) option this morning....though it's still very much open to debate as to what will actually happen. Hard to predict when you've got Leslie thrown into the mixer and how that interacts with the jetstream.

[BlueHedgehog074]

The models, such as the 00Z GFS, 00Z ECMWF and 00Z GEM continue to show a big knock-out occurring between the Scandinavian High Pressure to our East and the Atlantic Trough to our West in the Atlantic.

An example from the 3 models at 192 hours:

GFS

GEM

ECMWF

Surprisingly quite reasonable agreement between the 3 (although models such as the GFS have been hinting at blocking to the East with a flow from the South for a while now). The Lows digging deep into the Atlantic sorta helps to encourage High Pressure to build strongly to our East. I expect things will continue to keep shifting with Eastwards or Westwards adjustments to the overal pattern. The further East and the more power the Atlantic Trough has, the more it could claim victory over its rival (the Scandinavian High) to the East with more of the UK being under attack from Atlantic Lows and the wind and rain it would bring. But the opposite and the blocking Eastern UK high could claim more control over our island (Think damianslaw went into similar detail yesterday saying if High Pressure was further East, the more the Atlantic could smash through). As it currently stands, it could be Summery for a time with warm daytime temperatures. The best of the fine weather towards Eastern areas with Western areas of the U.K. more likely to see more in the way of windy and wet conditions at times. Especially close to those fearsome Lows out in the Atlantic. 

The 500mb 6 to 10 day mean chart from the NOAA does support a build of pressure over to our East towards Scandinavia with a mean flow between the South-West and South-South-West.

And showing some kind of possible North-West to South-East (perhaps West to East for a time) split occurring. Exactly settled or unsettled it may turn out to be overall for the U.K. will depend on surface features itself. 

Be fun to see how this continues to keep getting modelled and how long the likely the dual between both the Atlantic and the blocking Eastern UK High will last. Personally, another shot of Summer would be nice (but wouldn’t mind seeing some cold weather soon either, albeit tomorrow does look chilly, grey and wet for Southern UK areas with a slack Low to the South).

Edit: mb018538 above sums it up well.

Edited October 5, 2018 by DiagonalRedLine

[carinthian]

Morning all. A bit of a frustrated post this one until the new winter moaning thread opens ! Charts seem to be heading for a full usual October Bore Fest for much of Euroland. I hate October, weather wise, usually a month of nothingness, especially in Central Europe. Another 15 days under a warm high will test my patients to the limit. Counting the days for real cold and snow to establish on the mountain.  A trip to Canada beckons for some seasonal variety !

C

[Froze were the Days]

CFS ain't worth a jot!, I should know I've followed it to the precursor of the last couple of winters...