Model Output Discussion - Autumn 2018

[tinybill]

1 hour ago, Jonathan Rhodri Roberts said:

Saturday looks rather cold for the beginning of October on the GFS 6z highs struggling to even reach double figures for many! 

Acc seen a video via Facebook of it snowing in Malta!!

[mb018538]

ECM clusters this morning showing a deep Atlantic trough parked out to the west of the UK, NW/SE split, though it could be fairly mild to warm with a southerly feed:



By day 12 there is a split of outcomes, though still favouring the SE for the best of conditions:



At day 15 the ridge is in the largest cluster, though by no means conclusive:



The GFS ensembles also look fairly dry for the majority out to day 10, with the pressure mean reasonable too. Parts of the SE seeing little or no rainfall. Only the NW of Scotland really taking a bit hit closer to those lows and the track of the jetstream.

[Frosty.]

Next week would feel more like summer if the Gfs 6z operational is right, a very warm long draw southerly airflow with temperatures into the low 20's celsius..really nice.

Edited October 2, 2018 by Frosty.

[Jonathan Rhodri Roberts]

46 minutes ago, Frosty. said:

Next week would feel more like summer if the Gfs 6z operational is right, a very warm long draw southerly airflow with temperatures into the low 20's celsius..really nice.

Would be nice if it was dry and sunny but with low pressure (1010mb) in charge here in the west, we could end up being warm & wet

[Radiating Dendrite]

2 hours ago, tinybill said:

Acc seen a video via Facebook of it snowing in Malta!!

Will be hail - it has been low 20s with Thunderstorms there today.

[I remember Atlantic 252]

liking southerly breeze, upgrade on 6Z for start of the week

[Frosty.]

Looking at the Gfs 12z operational most of next week looks largely fine and very warm for the time of year with a continental s'ly / se'ly flow eventually the flow becoming more ssw'ly, especially warm further s / e with temps into the low 20's c, perhaps closer to mid 20's for favoured spots..more like summer!☺

Edited October 2, 2018 by Frosty.

[ItNeverSnowsInWindsor]

Glad the gfs 12z is a warm outlier!

Edit or maybe not!!

Edited October 2, 2018 by prolongedSnowLover

[Newberryone]

An interesting enough evolution from Tues to Fri of next week on the 12z Ecm with a standoff between the Atlantic meeting tough resistance it has to be said from the block to the east. Wednesday looking potentially quite wet and windy for parts of Ireland. Further on, active Atlantic lows seem to be kept well to the northwest. Question remains  though as to whether or not these are more general signs of a shift in emphasis from anticylonic to something more mobile. 

[DR(S)NO]

Talk of warm settled weather on here .... but surely not.... my copy of the Express tells me that Britain is going to endure 14 days of Ferocious Weather thanks to a powerful cyclone called Leslie thats hurtling across the Atlantic...

Any guesses as to what’s wrong here ?

[NO LONGER POSTING]

Seems to me a recurring theme in the GFS is to try and get low pressure systems to sweep in, but because of the block in place to the east they slide up to the west of us introducing some very warm weather for the time of year. Sucking up the warmer air to the south 

Was it Halloween 2015 that was crazy warm day and night temperatures? I'm not sure what year it was..

15c uppers getting in on this run... 

One thing we do need more of down south is rain.. And it's looking more and more slim chance in the next week or so Apart from Saturday afternoon /evening brief affair 

[mb018538]

2 hours ago, Surrey said:

Seems to me a recurring theme in the GFS is to try and get low pressure systems to sweep in, but because of the block in place to the east they slide up to the west of us introducing some very warm weather for the time of year. Sucking up the warmer air to the south 

Was it Halloween 2015 that was crazy warm day and night temperatures? I'm not sure what year it was..

15c uppers getting in on this run... 

One thing we do need more of down south is rain.. And it's looking more and more slim chance in the next week or so Apart from Saturday afternoon /evening brief affair 

It looks that way @Surrey. A bit of a recurring theme for something warm or perhaps very warm appearing around next weekend time:

https://www.theweatheroutlook.com/charts/gefs/gefsens850London0.png

With the ensemble mean hovering close to 10c (barring a dip this weekend), it looks like staying mild to warm with temps in the upper teens through next week, which would be well above average for this time of year.

[Jonathan Rhodri Roberts]

2 hours ago, Surrey said:

One thing we do need more of down south is rain.. 

Depends where you are in southern UK as here in South Wales, my weather station recorded 130.7mm in just a few days from the 3 'named storms' 2 weeks ago and also 75.8mm fell in just one day in the middle of August, so recently it's been a case of 'plenty of dry weather but when it rains, it rains'

[johnholmes]

Using the 500 mb anomaly charts, the 3 I use, are all in close agreement, it would suggest a NW-SE split with the most disturbed weather the further north and west one live. Less so for the SE corner but even here the upper air pattern suggests rain and wind here now and then.

My notes this morning 

Ec-gfs show ridging e/ne with major trough around 30 w; Noaa is also similar perhaps 25 w for trough

So all 3 now appear settled on this, the flow is strong away from se across atlantic , with the flow looking like right entrance, close to us- and left exit close to nw uk, some deep surface depressions seem likely in the 6-10, extending into the 8-14 as that shows a similar idea.

http://www.cpc.ncep.noaa.gov/products/predictions/814day/500mb.php

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

 

[Newberryone]

1 hour ago, johnholmes said:

Using the 500 mb anomaly charts, the 3 I use, are all in close agreement, it would suggest a NW-SE split with the most disturbed weather the further north and west one live. Less so for the SE corner but even here the upper air pattern suggests rain and wind here now and then.

My notes this morning 

Ec-gfs show ridging e/ne with major trough around 30 w; Noaa is also similar perhaps 25 w for trough

So all 3 now appear settled on this, the flow is strong away from se across atlantic , with the flow looking like right entrance, close to us- and left exit close to nw uk, some deep surface depressions seem likely in the 6-10, extending into the 8-14 as that shows a similar idea.

http://www.cpc.ncep.noaa.gov/products/predictions/814day/500mb.php

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

 

A resilient block to the east very much in evidence again on the 00z Ecm run ultimately sparing large parts of the UK from the worst of any wind and rain due in on a long fetch and no doubt moisture laden south westerly flow next week. As is usually the case in this type of weather setup Ireland seems pretty much guaranteed to see a rise in water levels. Of course, one can never discount the fact that these systems could be deflected further northwest in the next run owing to the block. 

[tight isobar]

Short/medium term diagnostics.

Although 'no notable' large scale differences....

The eye openers are there 'early on'..

A last gasp of early autumnal warmth aiding in the forward frontal onset of winter...perhaps?!..

A notable large lobe vortex push to an easterly caption!..

And although even @10hpa strat there is nothing of significance...at this point the overal conscientious is there!!..

Also the aiming/conversition of mid'-latt blocking steps are falling on exactions.

An alarming-punch of large mass waa keen for punch @mainland/mass eastern quad euro...

All this without looking @the shenanigans on the pacific side of northern hem-top global.....

Things winding up now...and decipher/watchings becoming ever more interesting.....

The ride has opened!!!!

[Frosty.]

I concur with John Holmes, the Ecm 00z ensemble mean does too!☺

[mb018538]

6z GFS is glorious in the mid to later term - warm and generally quite settled. If that floats your boat, it's not a complete outlier either....above the mean yes, but with some support:

https://www.theweatheroutlook.com/charts/gefs/gefsens850London0.png

Of course the ECM mean isn't in agreement, and the favoured solution at day 10 is the very strong atlantic trough being most dominant:



Staying broadly westerly out to day 15 too, better in the SE.

Edited October 3, 2018 by mb018538

[Mike Poole]

It's now looking increasingly likely that towards the weekend after next unseasonal warmth will be the order of the day, this possibility evident from the models for some time now. First GFS T240:

GEM take interesting with this 16C uppers over Shetland:

Here's the FV3 at T240:

that heat's gone a bit north no?

ECM at same time:

 

 

And apropos of nothing, today the CFS offers this at T1794:

Happy days  all round.

 

Edited October 3, 2018 by Mike Poole

[Spah1]

23 hours ago, DR(S)NO said:

Talk of warm settled weather on here .... but surely not.... my copy of the Express tells me that Britain is going to endure 14 days of Ferocious Weather thanks to a powerful cyclone called Leslie thats hurtling across the Atlantic...

Any guesses as to what’s wrong here ?

You bought the Express ?

I’m amazed the Mods are still allowing you on here

[Frosty.]

17 minutes ago, Spah1 said:

You bought the Express ?

 

He's just expressing his opinion

Moving swiftly on..it looks like  NW Britain  will bear the brunt of the unsettled atlantic weather with the SE least affected.

[summer blizzard]

Massive westerly wind burst occuring over the central and east pacific over the next week (one of the strongest on record i imagine).

I would look to significant ridging to the north and east developing in the final half of October.

[NO LONGER POSTING]

7 hours ago, summer blizzard said:

Massive westerly wind burst occuring over the central and east pacific over the next week (one of the strongest on record i imagine).

I would look to significant ridging to the north and east developing in the final half of October.

Somtimes having a block out east can be a pain in the butt if it's not far east enough a few winters we have had this issue I think. 

I still can't get over how stubborn the GFS is being with regards to next week's warmth... 

Some really crazy uppers being pulled up by the very deep low pressure systems that are expected to slide up the block and north. 

Its looking like after that happens, high pressure builds in yet again.. 

I wonder what it would look like if we could look at all the days over this year with pressure 1000-1020 mb or above and see how many that is.. More so the further south you go 

Edited October 4, 2018 by Surrey

[Leo97t]

Polar vortex formation looks a bit better on the Gfs than the horror show it was yesterday

[carinthian]

On ‎24‎/‎09‎/‎2018 at 12:08, carinthian said:

Just from a personal observation, not sure how useful these charts are that far out at 360t. Two important facts that are possibly not taken into consideration by the predictive data are as follows :

I.  Wind data from the tropics to the equator is still very sparse even with advanced satellite technology ( this will in the future be an important research area )

2.. Temperature differentials between the North Pole and the equators continues to diminish ( this will have an affect on pressure patterns that will continue to evolve to a different scenario to the normal)

Maybe this NH pressure chart that far out will be spot on this time but likely to be corrected on a daily basis, so in effect no use to anyone that far out.

C

Morning all. Regarding the above post, just this time last week most models were showing retrogression of the European high into October. This chart below from UKMO shows the reverse with  a strong build of pressure remaining in situ. Nice weather  where you get the sunshine but a bit of a October bore fest for those stuck under cloud and nothingness, if you know what I mean. However, despite all the numerical predictions of Leslies eventual track in 7 days time, wind data as highlighted in the above post remains sparse and the picture could well look completely different in the models this time next week.