Model Output Discussion - 17th Oct Onwards

[weirpig]

A pure nasty area of low pressure, but we all know GFS enjoys to ramp up the low pressure systems so I wouldn't be surprised to see this much weaker by then

 

yep if that were to happen quite a bit of damage will be done what with the wet weather and sodden ground. However long way off but certainly worth keeping an eye on.

[Summer Sun]

ECM ensemble unsurprisingly dismisses the idea of high pressure building over us at day 10

 

 

Op

 

[Zenarcher]

Comparing the models with the unsettled low pressure systems,

 

This Friday the main models agree on a strong low to the South of Greenland, most of them show it to be around 960mb,

 

 

However at just 96 hours there is a still some large differences between the models, the ECM shows it the weakest out of the runs tonight at about 970mb,

 

 

The JMA is the lowest out of them all at 955mb,

 

 

What happens next at 120 hours (Saturday) is still something the models are trying to figure out. Something like the ECM shows does have good support from some other models tonight with two lows in the Atlantic weakening,

 

 

Sunday and Monday (144 to 168 hours) the GFS places a low of 950mb over the UK,

 

 

You could say the GFS is overpowering the low which it is well known for but the ECM 00z run from this morning had a low over the UK its not as deep but builds up a similar picture,

 

 

None of the other models show a strong low like the GFS from the 12z runs and its ensembles didn't give it too much support on the strong low either.

Edited October 21, 2013 by weathermaster

[weirpig]

Well lets see what the pub run shows,got a feeling its still gonna run with this strong low, at least its something a little more interesting other than mild dross.

[bobbydog]

gavin will have a 'modelgasm' when he sees this!-

 

[Captain Shortwave]

Well as soon as NAEFs drops the high to the east/north east signal for week 2, the ECM and GFS ops are now starting to sniff at that solution. Given the tropospheric vortex is moving away from northern Russia and stretching between Siberia and Canada a block developing there has some decent logic to it. Tomorrows runs will be very interesting to see how things develop as the zonality we are entering right now might not last that long.

Whilst the ECM ens don't particularly back the operational, I have noticed increased amplification of the pattern into week 2 which again suggests the Atlantic might begin to calm down after it's 10 days or so of rage.

Edited October 21, 2013 by Captain shortwave

[Tamara]

Well as soon as NAEFs drops the high to the east/north east signal for week 2, the ECM and GFS ops are now starting to sniff at that solution. Given the tropospheric vortex is moving away from northern Russia and stretching between Siberia and Canada a block developing there has some decent logic to it. Tomorrows runs will be very interesting to see how things develop as the zonality we are entering right now might not last that long.

Whilst the ECM ens don't particularly back the operational, I have noticed increased amplification of the pattern into week 2 which again suggests the Atlantic might begin to calm down after it's 10 days or so of rage.

At this stage, I think that any potential blocking signal to the NE will be under too much pressure with the polar vortex too strong (based on its current stages of development) and with excess energy coming out of NE Canada. But that said, it is possible that jetstream energy may still be, relatively, exaggerated at distance with slightly more amplification present than predicted. High(er) pressure, eventually, over mainland Europe and towards southern UK may be closer to the reality - but time will tell

Edited October 21, 2013 by Tamara תָּמָר

[draztik]

Whilst the ECM ens don't particularly back the operational, I have noticed increased amplification of the pattern into week 2 which again suggests the Atlantic might begin to calm down after it's 10 days or so of rage.

the EC32 Monday update completely torpedoes that idea, as its once again unsettled from start to finish.

[SLEETY]

the EC32 Monday update completely torpedoes that idea, as its once again unsettled from start to finish.

 

 

And the EC32 has as much credibiltiy as James maddens winter forecasts

Edited October 22, 2013 by SLEETY

[The PIT]

The GFS 00oz pushes the dartboard low out back into deep FI so it's unlikely to happen. Otherwise it's pretty much more the of the same mild or very mild becoming less mild as winds swing more westerly. No sign of the ECM's idea of high pressure coming into play. Who's going to be right.

[Kiwi]

The GFS 00oz pushes the dartboard low out back into deep FI so it's unlikely to happen. Otherwise it's pretty much more the of the same mild or very mild becoming less mild as winds swing more westerly. No sign of the ECM's idea of high pressure coming into play. Who's going to be right.

The ECM has been decent over the last few winters when it comes to picking up on the development of  European high pressures .....so I'll be watching the next few runs with renewed interest.

[phil nw.]

The Atlantic wave train continues then with no sign of change yet.Temperatures dropping off somewhat with a more westerly element to the flow though as we lose those warm uppers from further south.

The main vortex looks pretty centralised over the Arctic now with only subtle variations.This would deter any heights building any further north than mid-latitudes so very much a +ve NAO/AO outlook.

[Frosty.]

There is currently very good support for a colder shot from the north through the first half of next week as low pressure makes more eastward progress and enables a backwash of cold air to flood down the western flank of the depression across the uk, there are many variations of this theme from the GEFS 00z perturbations with some more potent than others, even the Ecm 00z op run shows something similar and the GEFS 00z mean is very much on board. So...we could have a relatively much colder shot with a risk of wintry showers and widespread frosts for a few days next week before the pattern flattens out again but with such a turbulent pattern, I would imagine there would be further cold incursions in the pipeline in amongst the milder spells. For the time being it's extremely mild or warm for the time of year, but it's days are numbered, colder incursions are on the way as well as a lot more very wet and windy weather. 

make it so

[johnholmes]

There is nothing to change my view on the upper air pattern I've given over the last few days, any colder will certainly be a short lived affair. Until there is a marked change in the upper air then there is no prospect of anything longer term. 

The ECMWF-GFS output this morning shows the general pattern to be expected at 500mb out to the end of October and probably into early November. It is true that as the upper flow tends more westerly the temperatures will lower to more realistic late October numbers.

 

http://www.meteo.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

[Summer Sun]

Latest from Gibby

 

Good morning. Here is today's browse through the midnight outputs from GFS, UKMO, GEM, NAVGEM and ECM for today Tuesday October 22nd 2013.All models show a mild SSW airflow over the UK with Low pressure transferring slowly North and NE towards NW Britain. As a result unsettled conditions will prevail for all with heavy rain or showers across all areas today. Through the next few days things turn a little cooler as winds veer more Westerly but still with some heavy showers tomorrow in the North and West in particular. On Thursday a brief lull looks likely before further Low pressure tracks NE over the UK with renewed rain and wind late in the week. This then gives way to showers ahead of a strong Westerly flow that develops for the weekend with rain or showers for all and temperatures much less mild with values close to the seasonal average by then.

 

GFS then maintains very unsettled weather through the rest of it's run with next week particularly wet and maybe stormy for a time as an intense Low crosses the UK. The pattern calms down somewhat with regards to wind for a time before a renewed surge of Atlantic gales and rain in association with Low pressure to the North concludes the run. After the final few days of mildness is out of the way by the end of this week it looks like temperatures will fall to average thereafter and it is sure to feel much chillier than of late.

 

UKMO shows the start of next week as equally unsettled with a broad bank of Low pressure stretching from Scandinavia to Greenland on Monday with strong and unstable Westerly winds delivering rain and showers to all, some heavy. It will be noticeably colder than of late with temperatures close to or even just a little below or above average at times dependent of the origins of the air mass over the UK at the time.

 

GEM today continues to show the potential for some major storm systems crossing the UK next week with severe gales and heavy rain likely at times. A few brighter intervals would occur at times and temperatures will be much down on recent levels especially felt over the South.

 

NAVGEM too is very unsettled next week with Low pressure over or close to the North with a strong Westerly flow over all areas. Rain alternating with showers would be the order of the day and in the wind it will feel and be much colder than of late.

 

ECM keeps things very mobile next week with last night's phantom High pressure to the East as expected absent from the output today. Instead a very active Atlantic spawns some powerful Low pressure areas crossing to the North with spells of rain alternating with squally showers in gale force winds at times and temperatures close to the seasonal normal at best for all next week.

 

The GFS Ensembles show temperatures falling back over the next few days as the axis of winds change from West to East as opposed to SW to NE. The weather is shown by nearly all members to remain wet and windy for much of the period with some copious and heavy rain for all at times in a strong breeze. A few drier days are shown in between the rain bands but these look only very short-lived.

 

The Jet Stream which is currently blowing across the Atlantic over or to the South of the UK continues for a while longer before it moves ever so slightly North to the UK in general and occasionally Scotland but becomes very powerful spawning some very deep Low pressure areas close to Northern Britain next week with the resultant jet flow pulsating North then South ahead and behind weather systems.

 

In Summary today our prolonged period of very mild conditions is coming to an end. Over the next few days temperatures will begin to fall back towards average as the mild SW flow is replaced by a strong Westerly flow with a source at high latitudes over the North Atlantic. The weather is shown almost exclusively from all models to be often wet and very windy with severe gales possible next week should some of the output verify as intense areas of Low pressure cross over or to the North of the British Isles. Rainfall will be commonplace as a result, often heavy and prolonged and river catchment areas and low lying parts of the UK could become prone to cumulative flooding with time. With lower temperatures we have to begin to cater for the risk of snowfall on Scottish mountains at times though due to the strength of winds alone any significant frost anywhere looks very unlikely.

 

http://www.norton-radstockweather.co.uk/Model-Analysis%282859336%29.htm

[Summer Sun]

So today's daily express recon the winds this will be worse than the Great storm of 1987 on Sunday

 

Hmmm I don't think so!

 

Jonathan Powell's quote

 

“Next Sunday is looking very severe, and all signs are pointing to what could be the storm of the century.

 

 

Hardly "storm of the century" try typical Autumnal weather

 

This paper is rapidly becoming a laughing stock

Edited October 22, 2013 by Summer Sun

[Yarmy]

So today's daily express recon the winds this will be worse than the Great storm of 1987 on Sunday

 

Hmmm I don't think so!

 

Jonathan Powell's quote

 

 

 

Hardly "storm of the century" try typical Autumnal weather

 

This paper is rapidly becoming a laughing stock

 

That ship sailed a long time ago, Gavin.

[TwisterGirl81]

Metcheck are the first weather website that I've seen that has picked up the potential for a significant storm to hit Britain on Sunday eve/Monday apart from the models on here....at the moment the centre of the low would track across Wales so I am a novice but would that mean the strongest winds would on the southern end so southern England in the during line? What kind if winds would we expect if this verifies?

Sorry I'm a novice here

[Frosty.]

 

This paper is rapidly becoming a laughing stock

I'm reminded of a saying..believe nothing what you read in a newspaper and ½ of what you see, it works for me.

[ribster]

So today's daily express recon the winds this will be worse than the Great storm of 1987 on Sunday

Hmmm I don't think so!

Jonathan Powell's quote

Hardly "storm of the century" try typical Autumnal weather

This paper is rapidly becoming a laughing stock

Hyperbole no doubt, but 1987 was a diffferent century Gav.

[Captain Shortwave]

I'm reminded of a saying..believe nothing what you read in a newspaper and ½ of what you see, it works for me.

You are giving the papers far too much credit Frosty 

The models have returned to zonality all round this morning. It appears the ECM is even worse than the GFS at 8-10 day volatility 

[Steve C]

I see Nick F has been quoted in the Express too, although his comments are sensible.

[Frosty.]

You are giving the papers far too much credit Frosty 

The models have returned to zonality all round this morning. It appears the ECM is even worse than the GFS at 8-10 day volatility 

I'm pleased there is a chance of colder shots in the mix from next week onwards even though the overall pattern shows mostly mild spells, the cold potential is creeping in, especially the further north you are.

[johnholmes]

Metcheck are the first weather website that I've seen that has picked up the potential for a significant storm to hit Britain on Sunday eve/Monday apart from the models on here....at the moment the centre of the low would track across Wales so I am a novice but would that mean the strongest winds would on the southern end so southern England in the during line? What kind if winds would we expect if this verifies?Sorry I'm a novice here

 

don't let that stop you posting-as to what happens on Sunday then we need to see ALL the models suggesting the same as the time closes down to about T+48 before we can be sure of what happens. Even then rainfall amounts and where can be off the mark but the wind speeds should be within 10-15 knots of what actually happens by that time.

 

use the link below to see how the 3 main models show the system for the weekend, compare the last run for continuity. Eventually all 3 (when below T+144) will begin to converge on the probable position and depth of the low, assuming by then all 3 have decided that it is going to happen. Check also the Met Fax chart for Sunday as that comes in range, and how they change its position and depth.

Finally by T+24 the depth and position should be fairly certain, thus wind strengths will be known but rainfall totals and where will still be liable to change.

 

http://www.netweather.tv/index.cgi?action=modelcomp;sess=

 

Net Wx Fax chart link

http://www.netweather.tv/index.cgi?action=fax;sess=

Edited October 22, 2013 by johnholmes

[Iceni]

I see Nick F has been quoted in the Express too, although his comments are sensible.

 

OOI I wonder if we could get an archive of weather forecasts in the papers the week before 16th October, 1987. That would be fun and what if the Express had forecast "The Storm of the Century"? We might have to revise our opinions.

Edited October 22, 2013 by Iceni