Model Output Discussion 1200 hrs 30/09/14

[Barry12]

GFS at 384 hrs is interesting!

 

 

[LomondSnowstorm]

 

I think we all know there is a spell of zonal weather coming and although never say never with weather this is the clearest signal this Autumn that a change in that direction is coming. I did add that we need to watch this trend. The 06z keeps the mean pressure for London on a downward direction with some very wild members bringing wet and windy weather on a mainly zonal flow:

 

graphe4_1000_306_141___Londres-32.gif

 

The latest JMA update for week 2 and week 3 of November anomaly suggests the westerly flow will become established. That is a strong 2 week low pressure anomaly:

 

Y201410.D2212 (1).png

 

The CFS MJO is heading into Phase 2 early November and that translates to: 

 

realtimemjo (1).png  NovemberPhase2gt1500mb.gif

 

Then phase 3 for nearly the rest of November: NovemberPhase3gt1500mb.gif

 

How long we get locked into this pattern is debatable and there is no clear signal this will be anything other than a few weeks assuming this remains the trend.

 

Interesting comparison with both those charts to the November height anomaly for OPIs with values of -1 or less 

 

Aside from that, there is a bit of interest, particularly the further north you are, with the potential for Pm incursions with a bit of amplification upstream (as illustrated by that uber FI chart posted above). Still generally above average temperature-wise but daytime maxima near average:

Edited October 23, 2014 by LomondSnowstorm

[Barry12]

-Got a feeling the ECM 12z is going to be the best run of the season - watch this space.

[knocker]

GEFS still looking at bbove average temps becoming normal by the end of the run.

Edited October 23, 2014 by knocker

[tinybill]

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=2&ech=204

 

i know its deep fantasy world  are we allowed  to mention the s..w  word for scotland  or is it to early!!!

[Captain Shortwave]

-Got a feeling the ECM 12z is going to be the best run of the season - watch this space.

Not anything special really, just plain old westerlies, oh and a euro high

Nothing special, again a mixed bag but never swaying too far from average. Looks like the action is staying on the other side of the pole for now.

[Barry12]

Potential.

 

 

[ghrud]

Potential.

 

 

 

Potential?

[Nick L]

Potential.

 

 

 

Care to elaborate for those who aren't seasoned model watchers?

[knocker]

Your starter for ten

 

[knocker]

Comparing 6-day forecast from ECMWF & GFS 12z suggests satellite issue ironed out. AC=0.89 typical level of agreement

https://twitter.com/RyanMaue

[damianslaw]

Very much an unsettled outlook for the remainder of the month -very typical for the time of year, this is notorious for being one of the most unsettled periods of the year with the atlantic in ascendancy.

 

Staying mild especially in the south east, though north western parts will see temperatures nearer to average by day, but fairly mild at night with little chance of frost and fog thanks to cloud and too wind.

 

Looking further ahead into the start of November, no obvious signals of a significant pattern change, but lots of uncertainty where the jet will decide to position itself, subtle hints it will begin to move southerly again allowing for a more meridional flow to establish itself which would allow more seasonal temperatures and allowing polar air to invade. Not much gusto in the atlantic neither.. 

 

The way I see things is a very gradual slow descent to a more sustained period of seasonal temps, as the jet increasingly digs south as we move through early November after what will be a very mild latter part to October. 

 

In the meantime, its a very drab uninspiring outlook for anyone looking for early winter snow on higher ground, frost, fog, gales, sunny dry weather, cold conditions .. all courtesy of the torrid southwesterly - an airstream I personally despise! with all it associated low cloud, gunk and homogenity - its the airstream which gives a new meaning to the word 'grey'.

[phil nw.]

Indeed no real change in the overall pattern is showing in the models this evening.

It seems we continue with another week or more of rather mild south westerlies bringing a lot of cloud and occasional rain.

http://www.wetterzentrale.de/topkarten/fsukmeur.html

The far north west could see a lot of rain from more active frontal systems as the jet wavers across that region over the next few days bringing some temporary cooler incursions of pm air.

Generally though rather a drab,damp and mild period with temperatures remaining well up,especially at night.

The only positive I can take from this set up is that the heating costs are reduced whilst it lasts.

[legritter]

Looking at tonights charts not much of a change coming our way ,but as othershave pointed out ,perhaps a saving on the heating bills and some slow moving weather fronts bringing some steady rain to favoured locations depending how synoptics set up .but we have many weeks of winter wonderland ahead gang ,tidy up those prams sharpen the razors stock up on the prozack ,but we Can look forward to some good debate on Net weather ,the best forum around .

[BlueHedgehog074]

Not the easiest chart in the world to read I have to admit (despite having tried using them before). However, tonight's NOAA 8 to 14 day 500mb anomaly chart seems to show quite a Westerly driven pattern. A postive, but perhaps not a particularly strong, anomaly to the South of the UK with negative anomalies to the West and North-West of the UK. Together, with a keen Westerly to South-Westerly flow at the 500mb level (the green line), would suggest the idea of Lows streaming in from West to East to the North of the UK with High Pressure likely to stay situated to our South or South-East. So would agree with Phil that nothing particularly cold looks evident... for now! It's possible that High Pressure could try to build more to our East at times (which could sometimes change the flow more towards the South or South-East, especially if Lows become cut-off and drop away South-Eastwards through, or to the West, of the UK).

Moreover, the anomaly chart appears to show some fairly strong anomalies over the Northern and North-Western part of the Northern America area - chances of ridging of High Pressure around that part. Their also looks to be an area of negative anomalies to the West of that with some kind of troughing to the West of the Northern Western part of the Northern American coast. The 500mb flow shows a bit of a 'bump' around the North-Western America area. This of which could suggest the buckling of the flow in that region. And could perhaps help send some amplified High Pressure ridges downstream at times. As such, the occasional cooler/colder flow from the North-West probably can't be dismissed (particularly if the Vortex doesn't become too powerful to the North-West and try to flatten amplified ridges further West). I admit some of that is just guess work though. Otherwise, it looks to be a pattern of cyclonic conditions to the West or North-West of the UK, and higher heights to the South, South-East and/or East. The South-Eastern parts of the UK indeed likely to see the least in the way of disturbed weather and the area to see the mildest conditions.

Edited October 23, 2014 by DiagonalRedLine

[knocker]

Tonight's D10 and further outlook anomalies.

 

Essentially trough south Greenland lying NW/SE over the UK with the warmer air to the south and east. HP over N America of no great intensity and a trough eastern Pacific that the GEFs makes more of than the other two. Development of the PV Siberia. The jet is zonal but fairly weak. So same as, same as with a westerly unsettled flow with perhaps less unsettled in the south with the temps continuing above average.

 

Further ahead not much change except the possibility of the cooler Atlantic air becoming more dominate with periods of very unsettled weather and more average temps. Certainly no sign of any colder incursions.

Edited October 23, 2014 by knocker

[Yarmy]

Brief toppler on the pub run:

http://modeles.meteociel.fr/modeles/gfs/runs/2014102318/gfsnh-0-252.png?18

But will it be enough to shake Eugene out of his mild blues? :-)

[Mucka]

Brief toppler on the pub run:

http://modeles.meteociel.fr/modeles/gfs/runs/2014102318/gfsnh-0-252.png?18

But will it be enough to shake Eugene out of his mild blues? :-)

 

I will wait for winter, even this would be a waste in early November. (p17 18z)

 

Edited October 23, 2014 by Mucka

[knocker]

ECM monthlies update including the Arctic. Much of the same with perhaps more influence from the HP

 

 

[Nick L]

Yep, a look at the ECM monthly ensemble graph shows average to slightly above conditions continuing for the foreseeable. We do seem to be a bit locked into this westerly pattern at the moment.

[knocker]

Away from the long term a brief snapshot of some warm weather? Front orientated N. Scotland.

Edited October 24, 2014 by knocker

[Gibby]

HERE IS MY LATEST ANALYSIS FROM THE OUTPUTS OF THE WEATHER COMPUTER PREDICTION MODELS FOR TWO WEEKS FROM 8AM TODAY FRIDAY OCTOBER 24TH 2014.

 

NEXT UPDATE SATURDAY OCTOBER 25TH 08:00

 

The General Synopsis. Troughs of Low pressure will clear slowly away East across Southern Britain today with

further showery troughs in the NW blown in on very strong WSW winds.

 

Two Week Headline. Mostly mild and changeable with rain at times especially in the North and West but with some short drier and brighter spells too especially in the South.

 

The Jet Stream Forecast. The overall thrust of the Jet Stream over the coming two weeks continues to blow strongly

from the West or SW across the Atlantic and the North of the UK for the foreseeable future.

 

GFS Operational. Todays operational run shows mild SW winds largely in control over the UK over the coming week

with a weakening of the flow for a time midweek as a decaying cold front slips SE over the UK. Some rain is likely

for all as this change takes place with cooler conditions following on. However, by next weekend more Atlantic

depressions re-invigorate energy from the SW with mild weather returning with rain towards the NW. Through Week 2 the

trend is for a greater chance of cooler and more settled weather to slowly develop as higher pressure develops

across the UK with mist and fog developing widely at night, probably slow to clear by day by the end of the run as

winds fall light.

 

GFS Ensembles. The GFS Ensembles are relentless in maintaining winds from a West or SW direction throughout the

run this morning as the status quo of Low pressure to the North and NW and High to the South and SE persists. As a

result the theme remains for generally mild and somewhat unsettled weather with the majority of rain and wind

towards the North and West while the South and East sees decent dry and at times bright spells.

 

UKMO. UKMO today shows a spell of slack winds towards midweek as a cold front clears SE. Rain would give way to

fine and bright weather with mist and fog in places before mild South or SW winds pick up again later in the week

with rain once more focused towards the Northwest.

 

GEM. GEM today shows a mild SW flow backing Southerly later next week as a large Atlantic low becomes dominant.

With time this is shown to extend further East and NE towards West and NW Britain with all areas becoming under

increasing risk of rain and showers, heavy at times in mild SW winds.

 

NAVGEM. NAVGEM shows a quieter period midweek as High pressure develops following a trough SE. Early rain clears

to leave a dry and bright couple of days with cooler temperatures and overnight mists and fog. Thereafter a large

Atlantic depression inches in closer to the UK strengthening the mild Southerly flow and delivering rain at times

to most parts by next weekend.

 

ECM. ECM follows this general theme as well with increasingly unsettled weather for all areas and not just the NW

following the quieter period midweek when cooler weather could generate decent days but foggy nights for a time

before the milder, unsettled and breezier weather returns later. There remains a hint of a pattern change right at

the end of this run with much colder air waiting in the wings to the NW under higher pressure in the days that

follow the end of the run.

 

MY THOUGHTS. October is certainly going to end up a very much milder month than average, something which has been

all very common through this year. In the coming few weeks the weather largely remains Atlantic based with High

pressure to the SE and Low to the North and NW maintaining a broad scale North/South split in the weather. However,

nothing in model analysis is as straightforward as that and there are a couple of intervals in this pattern when

there is scope for something a little cooler. One such occasion is towards the middle of next week when a weakish

area of High pressure could deliver a couple of cooler more quiescent Autumn days with a fog risk at night

following a weakening cold front SE. Then as usual other chinks in this basic pattern appear far out in la la land

with ECM the cream of the crop on Day 10 where Low pressure looks like eventually edging away to the East in the

days that follow the run and allowing the chance of colder air from Iceland and the Arctic to drift down across

the UK under rising pressure. However, having mentioned that it again is just one run in isolation and I see

nothing in any ensemble data and Jet Stream prognosis to suggest that anything other that the large percentage of

the next few weeks will remain mild and benign with the most rain and wind from autumnal Low pressure focused

greatest towards the North and West while Southern and Eastern parts in particular see plenty of dry and bright

weather with only more occasional lighter rainfall at times.

Edited October 24, 2014 by Gibby

[Summer Sun]

Just noticed on wetterzentral a new model called Icon has appeared it only goes out to t78

 

 

http://www.wetterzentrale.de/topkarten/fsicoeur.html

[kev238]

It has to be said, looking at the models, that next week looks incredibly mild- almost warm .

Temperatures according to gfs into the high teens across much of England .

This is also backed up by my weather pro app ( based on ECM model I think ).

In my opinion, there needs to be a big shift in weather patterns if we want colder weather this winter as we seem to be in an unrelenting pattern of milder with one blip in August - good for heating bills though!

[knocker]

The ECM anomaly for next weekend has a trough to the NW of the UK with HP to the south and east. Depending on the orientation of these two air masses will decide the UK weather. The GFS is not making so much of the trough so HP more dominant. Average temps.