Model Output Discussion 31/07/14 onwards.

[Nouska]

Interesting to think that currently.

 

That wave is not TS Bertha, she is further SE..This new area of interest would take similar path to that of Arthur. We shall see how it goes

 

pic.twitter.com/jvSogZpEOq

 

Running this loop of the Atlantic from the GFS clearly shows the source of the vorticity is in the region where Bertha is currently.

The NHC also show the forecast track to be similar.

 

http://www.tropicaltidbits.com/analysis/models/gfs/2014080306/gfs_z850_vort_atl.html

 

[IDO]

Latest GFS members tracks for Bertha:

 

Certainly looks like the track has high confidence to interact with the trough in our region.

 

Just to highlight how much of an outlier ECM op was for temps: 

 

ECM looks like a wet one for many Friday:

 

GFS has the rain, but further north:

 

About 22c in Heathrow at the moment and looks like 22-26c maxes this week for the SE.

 

 

[Stormyking]

The charts definatly seem to be turning this week wetter and wetter as each run goes by, got one load on Wednesday Morning which the GFS seems keen with a heavy pulse of rain showing.

 

 

There also seems to be a good of showers as well in alot of places this week, and then you have friday which has been showing to be another wet day for many, but I have a feeling there could be some thundery showers in the mix aswell, and i reckon it could feel quite warm and humid too.

 

 

12Z soon, so will be interesting to see what changes happen then

[Gael_Force]

Interesting to think that currently.

 

That wave is not TS Bertha, she is further SE..This new area of interest would take similar path to that of Arthur. We shall see how it goes

 

pic.twitter.com/jvSogZpEOq

 

Indeed, maybe an amalgamation and lots of extra tropical 'juice'.

 

[legritter]

Its realy great when we get a very interesting synoptic situation in the outlook ,great for interest on our forum with charts firming up day by day .Currently the end of this week is looking like it could go several ways looking at todays charts and reading latest Met office further outlook ,but as many have pointed out with all that Energy out in the Atlantic its going to be hard for any Weather Model to get close to positioning at this range .But certainly looks like many different air masses will be in play so lets all enjoy the twists and turns as we go through this week .

[Frosty.]

Nice to see a large atlantic / azores anticyclone trying to build in during the low res part of today's Gfs 12z op run, I hope this becomes a trend which then gathers momentum on subsequent runs.

[mushymanrob]

Nice to see a large atlantic / azores anticyclone trying to build in during the low res part of today's Gfs 12z op run, I hope this becomes a trend which then gathers momentum on subsequent runs.

 

until it has anomaly chart support though its nothing more then eye candy mate.before then we have bertha to contend with and that looks like shaking things up considerably. whats the betting the 12z gfs is right and it steams right across us?... lol.

[draztik]

 

GEFS Height Anom days 0-16 12z

 

Quite an outlook! the trough now looks to be given full control over proceedings into the mid term - affecting all parts, not just confined to the West. GEFS still keen on wanting to install a Scandi trough by mid month; whether that sees the light of day, who knows.

Edited August 3, 2014 by draztik

[knocker]

Just quickly the GFS and ECM anomalies for 00 Sat.

 

 

[summer blizzard]

Some pretty incredible charts being shown tonight for rainfall.

 

Here we have the Euro with the type of chart which produces front after front of heavy and persistent rain..

 

 

And here we have the GFS playing spot the UK...

 

 

And finally we have the GEM assesment of the week ahead..

 

Wednesday..

 

 

Friday..

 

 

Sunday..

 

[IDO]

Bertha has cancelled Summer for a while and looks like bringing a taste of Autumn. ECM has finally ditched it's track for the ex-storm and is now showing sensible charts, though they are probably overdoing the deepening of the low(s):

 

D7 ECM:  D7 GFS:   GEM: 

 

Timing issues as well as intensity variations. The GEFS have a mix of calmer seas to bog standard Atlantic low to an ECM special.

 

GEM at D10 back to square one: 

 

ECM at D10 lining up another one: 

 

GFS remaining under the trough as it edges east: 

 

Early days but certainly a postponement of any prolonged heights. So potential for lots of rain aligned with cooler temps.

[Captain Shortwave]

Any calls of certainty in the mid range I think is rather premature, I think another 24 or more hours will be needed to determine the track of Bertha and whether it hits the UK or ends up somewhere completely different. Whilst the ECM looks to have built heights too close to the UK, it was always more likely to verify than the GFS which has now finally decided to show Bertha tracking this way instead of showing little interest in the system whatsoever.

Our potential downfall comes again from developments preceding this system.

The low crossing the UK through next weekend is now a more significant feature and hence digs more cool air into our block to the East, inflicting more damage and acts as a magnet for Bertha to strike the UK. The day 6/7 charts look like a low pressure soup with some unusually deep depressions in the UK vicinity.

 

Whilst the models all look unsettled, the pressure patterns all differ with respect to how these lows interact and the fact that the day 5/6 charts on the ECM differ greatly from this morning suggests we are still in a state of flux and hence should not tie our mast to this particular outcome for a few runs yet.

[knocker]

I think perhaps a tad longer than 24hrs Cs. The HWRF position Friday.

 

 

[Frosty.]

Tonight's Ecm 12z op run shows potentially very nasty weather by early in FI with much cooler, very wet and windy weather spreading from the west by the end of the week ahead. In the meantime it looks like sunshine and scattered showers, some heavy and thundery and temperatures into the low 70's F, a bit higher for the southeast and lower in the far northwest. It then stays unsettled and cool with a trough over the uk or to the northeast bringing more showers, not very summery tonight guys.

[IDO]

Any calls of certainty in the mid range I think is rather premature, I think another 24 or more hours will be needed to determine the track of Bertha and whether it hits the UK or ends up somewhere completely different. Whilst the ECM looks to have built heights too close to the UK, it was always more likely to verify than the GFS which has now finally decided to show Bertha tracking this way instead of showing little interest in the system whatsoever.

Our potential downfall comes again from developments preceding this system.

 

The low crossing the UK through next weekend is now a more significant feature and hence digs more cool air into our block to the East, inflicting more damage and acts as a magnet for Bertha to strike the UK. The day 6/7 charts look like a low pressure soup with some unusually deep depressions in the UK vicinity.

 

Whilst the models all look unsettled, the pressure patterns all differ with respect to how these lows interact and the fact that the day 5/6 charts on the ECM differ greatly from this morning suggests we are still in a state of flux and hence should not tie our mast to this particular outcome for a few runs yet.

 

Hi

 

I think GFS picked up Bertha before GEM, certainly before ECM. e.g.: 12z on 28th July at T264: 

 

It also had the block to the east and the trough over the UK. It was always looking like when Bertha crossed the Atlantic it would interact with the trough/jet and then hit the block.

 

In fact all models this evening are close to the same track, the storm having to ride over the Azores and then gets propelled by the jet stream, that is forecast to run through the UK at the end of next week. I think the uncertainty is how Bertha develops once it meets the jet. ECM still has the storm running the jet at D6:

 

And it is D7 when it slips into the trough: 

 

GFS op has it exiting the jet at D6:  And it cannot interact with the core of the lower heights further east.

 

However the GEFS have at least 33% support closer to the ECM timing. Some of the members:

 

 

 

I think good confidence that Bertha will target the UK, just what potency it will be when it arrives remains up for debate? 

 

 

[ANYWEATHER]

Will be very interesting, to see how ecm and gfs deal with tropical activity in the days ahead..ecm looks very nasty, gfs less so, but both models show an abrupt end to the Summer weather.....

[Polar Maritime]

Yes a very unsettled run from the ECMWF this evening and GFS once again, With maybe the ECM taking it to the extreme...? Many more runs yet before this gets resolved at 6/7days out.

 

As I'm Dreaming states, There is a very good probability of the Bertha hitting the UK. The question is, Is it going to be a big Bertha...

 

Edited August 3, 2014 by Polar Maritime

[Summer Sun]

Once again the ECM Op and ens have different solutions with the Op going for deep lows and the ens less so

 

 

ens

 

 

Until the track of Bertha is sorted its going to be a case of wait and see

[Man With Beard]

Can't really add much to the informative posts above - except to add that the notion of a NW/SE split this week is also pretty much off the table too, - from Wednesday onwards it looks as if secondary systems moving around the main upper low will now penetrate further south and so instead it will be the warm sunny spells at a premium everywhere, rather than the rain. The fax charts for Wednesday signify the beginning of this next phase:

Still potential for one very warm day in the SE but that's if the next set of fronts don't win the race:

Basically it's going to be a case of make the most of any summery days if this is your week for a UK holiday.

 

On to the weekend - bit of a lottery still but clearly potential for severe gales which could cause absolute chaos at this time of year. As others have said, we'll need to wait a bit longer to have any idea if we are to be the bullseye, and tbh even if there is one.

 

The longer term effect on the weather? If it develops, I'd say 30% chance of the "storm" encouraging heights by either stalling short or pushing the trough further away - but probably a 70% chance of the upper trough being reinforced in some way, leading to trough dominated proceedings for at least a few days after. Don't hold me to that though

[Cloud 10]

Bertha/ex-Bertha entering stage left on the latest 96hr fax chart.

 

[johnholmes]

Bertha/ex-Bertha entering stage left on the latest 96hr fax chart.

 

http:////f1.nwstatic.co.uk/forum/public/style_images/tctc91_simplify/attachicon.giffax96s.gif

 

and also shown on 120h Fax

http://www.weathercharts.org/ukmomslp.htm#t120

an interesting week as Met try to pin its track correctly; an idea to keep the Fax charts and compare how it tracked with how it was predicted to track-anyone?

[Captain Shortwave]

Charts at day 6

GFS

Weak ridge over the south but with Bertha bearing down on us, hits Scotland head on.

 

UKMO

Looks similar to last nights ECM at this time, direct hit again looks likely.

 

GEM

A little further west and as a consequence Bertha slides up the western side of the UK. The east doesn't get hit too bad in the end and it does temporarily become very warm.

 

ECM

Bertha showing to have little or no impact on the UK.

 

So 3/4 models going for a hit on the UK, but with the ECM now showing Bertha to simply ride the jet stream and dissipate then there is a lot of uncertainty about this system still. More runs needed, which is to be expected in situations like this.

Edited August 4, 2014 by Captain shortwave

[Frosty.]

The Gfs 00z op run turns increasingly unsettled during the next 7 days, the most unsettled phase being the weekend into early next week which look autumnal with cool, windy and wet weather, mid month looks more settled though. In the meantime it looks like a mixture of sunshine and scattered showers, some heavy and thundery but feeling pleasantly warm in the sunny spells with temperatures into the low 20's celsius, especially towards the southeast but then it looks like becoming cooler and very unsettled by the end of the week.

Edited August 4, 2014 by Frosty.

[knocker]

A quick look at the GFS and ECM anomalies. Both have the trough to the NW of the UK, the ECM showing Berha in western Atlantic, with associated low pressure on the surface.This will tend towards a N/S split with it being quite warm in the south.

 

The HWRF has Bertha still in the eastern Atlantic Saturday so I'm not about to call this one. I'm not sure whay Cs means by 'riding the jet stream, but the ECM certainly has Bertha dissipating in the western Atlantic.

Edited August 4, 2014 by knocker

[Polar Maritime]

Yes some quite unsettled/cool & Autumnal charts showing again this morning by the GFS, With Ex Hurricane Bertha still Model'd to cross the UK around the 11th.  I'm sure we will see many adjustments N/S over the next day or so, Interesting times ahead.

 

Edited August 4, 2014 by Polar Maritime