Model Output Discussion - 30/6/2014 Onwards - Covering July.

[damianslaw]

Models continue to show proper heat building as we move through next week, with as others have stated 30 degrees distinctly likely by Thursday/Friday - meaning the warmest conditions of the summer so far. It does have a classic plume spell written all over it, a shortlived very warm/locally hot spell for some before the return of cooler westerly airstream. Very typical charts as we move into the start of 'high summer' - not a patch on this time last year mind! but very decent all the same - with perhaps major thundery outbreaks by next weekend.

[bluearmy]

Extended ens sniffing around another push n of the euro ridge week 2 - probably a detached transient azores ridge heading east as per this coming week.

[summer blizzard]

The Euro sticks to the hot spell being warmest and lasting longest, GFS and GEM would likely breakdown too quickly for 30C (or rather break out with storms).

 

[Summer Sun]

Monday sees temperatures in the low to mid 20's for England the south could get to 25c but anything higher looks unlikely rain moves in from the west as the day goes on but it shouldn't reach the south

 

 

Tuesday again sees temperatures in the low to mid 20's somewhere could hit 26c dry for most

 

 

Into Wednesday and the heat starts to build mid 20's widely for England maybe 30c in the London area dry for most of England despite the heat

 

 

Another very warm day on Thursday possible hot in parts of the south temperatures widely in the mid 20's for England and Wales Scotland and Ireland continues with the fresher temperatures maybe 30c in the London area increasing risk of thunderstorms during the afternoon as the heat builds

 

 

Still warm on Friday but the maxes just edging down slightly heavy thundery rain possible

 

 

Fresher for all by Saturday with temperatures in the high teens / low 20's still the chance of some thundery rain

 

[IDO]

GFS 12z again keeps the ridging flatter than the other models and the highs are probably lower by 2-3c than this morning's ECM. Again its a N/S split but the SE should still hit 24-27c Wednesday to Friday, with the breakdown in the SE late on Friday and looks like it will be stormy:

 

  

 

Scotland and the NW looks like mainly average temps based on this GFS op run.

 

From the weekend GFS sees the pressure fall and a LP system sets up towards the NW, temps returning to nearer average:

 

 

UKMO also flatter this evening and like the GFS lowers longevity and intensity of the plume:

 

D5:   

 

 

[IDO]

Seems GFS is on the right trail with regard to the amplification as GEM is now flatter and therefore quicker at pushing the ridge through:

 

This morning:  12z: 

 

The uppers slightly warmer as they clip the SE next Friday: 

 

But again by the weekend LP rules: 

 

UKMO also a wet breakdown for the S/SE next Friday: 

[bluearmy]

we know ecm has a history of over amplification but we also know that gfs does the opposite !  ukmo difficult to jusdge becasue the T144 low is defined rather than a trough extension. to me, that looks like it could reload from the sw within a couple more days. gem 12z is so different to gem 00z with the atlantic low which just about sums it up - as has been the case for weeks now - the overall broad patten seems well predicted but any detail within that is very tough to pin down, even within five or six days.

[stodge]

Evening all

 

Well, the GFS 12Z Operational continues where it left off last night and for a change I'll use the 850s for T+144 as all the hope casting on here has been about the heat:

 

http://modeles.meteociel.fr/modeles/gfs/runs/2014071212/gfs-1-144.png?12

 

A continued downgrade on the heat from yesterday thankfully with the 12c isotherm fringing the SE but soon clearing off. Warm yes but not uncomfortably so.

 

On the other hand, GEM produces a much warmer chart:

 

http://modeles.meteociel.fr/modeles/gem/runs/2014071212/gem-1-144.png?12

 

The 16c isotherm has landed and the 2m temperatures reflect that:

 

http://modeles.meteociel.fr/modeles/gem/runs/2014071212/gem-9-144.png?12

 

Add a bit for the heat island effect and a couple of hours more sunshine and London could easily be around 30c.

 

UKMO very similar to GFS and generally much less enthusiastic about any heat plume from Iberia:

 

http://www.meteociel.fr/ukmo/runs/2014071212/UW144-7.GIF?12-19

 

NAVGEM follows GFS/UKMO to some degree. The encroaching of the Atlantic forces the heat plume to buckle East away from the British Isles:

 

http://modeles.meteociel.fr/modeles/navgem/runs/2014071212/navgem-1-144.png?12-18

 

ECM still to come and this could be critical for the end of next week. If it follows GEM, there will be a fascinating model stand off but if it follows GFS it will be kudos to the latter who spotted this lessening of the plume first.

[bluearmy]

ecm scrapes the 18c isotherm into kent at day 6 !!  the op looks wet next weekend but then again, its the op at day 6/7 so we have to bide our time re the detail.

[Polar Maritime]

Yes, Especially in these plume type set-up's, With lot's of regional variations. Lot's of chopping and changing in the Models re-detail over the next few days.

Edited July 12, 2014 by Polar Maritime

[IDO]

No change from the ECM Op. More amplified so we have the ridge hanging close to the east on Saturday supporting sustained higher uppers:

That would be interesting for the S/SE. By Sunday the temps fall, though still above average temps for many:

I think that a trough running through the UK has always looked the call for week 2; the JMA update highlights this:

So no sustained pressure rise on the cards, just a transient ridge. It is now whether we can maximise the temp potential next week in the 3-4 days that the models suggest for that plume and the models differ on this...

Edited July 12, 2014 by i'm dreaming of...

[Captain Shortwave]

Evening all

 

Well, the GFS 12Z Operational continues where it left off last night and for a change I'll use the 850s for T+144 as all the hope casting on here has been about the heat:

 

Well lets see.

All operationals this morning were showing very warm or hot conditions this morning, GFS the least enthusiastic and least consistent in output.

Ensembles backed up a very warm end to the week with this continuing into part of the weekend (lets keep any definition there ambiguous).

Metoffice forecast for next week suggest very warm or locally hot conditions.

 

So in reality, are people posting charts which show high temperatures really hopecasting?

If it is then we might as well just close the thread to be honest.

 

So models

ECM is still hot with a Atlantic breakthrough Saturday night into Sunday, so pretty much the same as this morning.

UKMO day 5 to 6 transition looks very very quick, probably too quick, but it is less amplified than the ECM so make of that what you will (breakdown on Saturday daytime?)

GFS develops a secondary shortwave trough which helps take the trigger low north east instead of slowing and moving south/south east (AKA develops the hottest conditions)

It's the low just west of Ireland, this steers everything over the ridge, the result is a flatter solution. 

 

GEM shows the same low but is slower with the breakdown, so a little more amplification and hence warmer for longer.

 

GFS ens show a breakdown on Friday, though the east will stay very warm through that day.

 

Again it's little features which will never get picked up at the day 5+ range which are causing headaches here. The ECM is very different to the other models at days 4 and 5, so at the moment is in the position of being on the block with the axe dangling overhead. I for one hope that it is correct and the others are having a wobble, if not it's not only a blow for those who love some proper heat, it's another blow for the trust of the ECM as an accurate mid-range model (5-8 day and earlier in this case)

[shaky]

Once again ecm has the plume for the end of next week!!this time the 15 degrees isotherm goes straight up into yorkshire. ......

[Methuselah]

Just so long as the 30C isotherm stays more or less where it is...

[Summer Sun]

Once again ecm has the plume for the end of next week!!this time the 15 degrees isotherm goes straight up into yorkshire. ......

 

Yes looking very warm / hot on ECM this evening for a time

 

 

Some torrential thunderstorms late next week a possibility if the low to our west makes inroads

[ANYWEATHER]

Ecm has been very keen to bring more meat on the bones with regard too a plume effect at day 6/7 around about T+144. Gfs has been very consistent  ,with a half hearted attempt at a plume. Perhaps we will end up with a halfway house of both models? Certainly interesting viewing ,but from the experience ive had over the years , plumes are very difficult to model, and often they overestimate the signal. Both models agree on a return to more Atlantic driven weather next weekend...    

Edited July 12, 2014 by ANYWEATHER

[Captain Shortwave]

ECM ens back the operational in the early stages

 

So that's the ECMs hand firmly shown here, could the ensemble suite for the ECM be completely off the mark here? The later stages are fairly similar, though with members showing the low not digging as far south as the operational does during Friday and the weekend.

Edited July 12, 2014 by Captain shortwave

[stodge]

Well lets see.

All operationals this morning were showing very warm or hot conditions this morning, GFS the least enthusiastic and least consistent in output.

Ensembles backed up a very warm end to the week with this continuing into part of the weekend (lets keep any definition there ambiguous).

Metoffice forecast for next week suggest very warm or locally hot conditions.

 

So in reality, are people posting charts which show high temperatures really hopecasting?

If it is then we might as well just close the thread to be honest.

Not at all - some people like and want the heat and select charts which show that. I don't like high heat and humidity and try to show some other options.

 

I think the balance has moved away from some of the hotter options from earlier in the week though I appreciate that, as others have said, modelling these plumes is complex and things can change at very short notice (just like an E'ly in January).

 

In the cause of balance though ECM does promise a warmer solution with the 16c isotherm across Eastern England. I would argue that represents a step away from Friday's 12Z and earlier output which offered a stalling LP to the SW and a hot SE'ly flow  

 

http://meteociel.com/modeles/ecmwf/runs/2014071212/ECM1-192.GIF?12-0

 

Oddly enough, it's the Azores HP which spoils the party by maintaining its position and forcing the LP north and introducing cooler Atlantic air. Fans of heat would prefer the LP to push the Azores HP away to the SW in order to set up the flow of hot continental air.

 

http://meteociel.com/modeles/jma/runs/2014071212/J144-7.GIF?12-12

 

JMA not too far from ECM though not as pronounced.

 

At the moment all these warm air incursions are brief and the Atlantic air comes through. To be fair, there are plenty of signs of settled warm (not hot) conditions in the further output especially for the south under the Azores ridge.

[knocker]

The ECM ens has the incursion of the low pressure over the weekend but still keeping above average temps, particularly in the south (26C-30C) until Sunday.

Edited July 12, 2014 by knocker

[Polar Maritime]

Can we try and not discuss who like's what weather type in here please, There are other threads for that.

 

Many Thanks. PM

[draztik]

To be fair, there are plenty of signs of settled warm (not hot) conditions in the further output especially for the south under the Azores ridge.

Days 8-14 height anom.

Looking at the anom. charts mid term, the setup is not exactly all that settled. Be it NOAA, gefs or the ext ecm.

[damianslaw]

5-6 days away is always a long time in weather forecasting - so far too early to call with confidence how much of a 'plume' may verify later next week. There is a stand off of sorts between ECM and GFS and to be expected at such a timeframe.

 

Forecasting a southerly plume is the same as forecasting a deep seated northerly- very often we see the models yo-yo around with various degrees of potency until the 24-48 hr timeframe. Unfortunately for lovers of extreme cold and heat, the end result is often a 'toppler' effect with the atlantic quickly crashing in.. not always the case mind.

[bluearmy]

Days 8-14 height anom.

Looking at the anom. charts mid term, the setup is not exactly all that settled. Be it NOAA, gefs or the ext ecm.

This has looked the direction of travel for week 2 for a while now - however, the anomolys dont look very strong so i would caution taking too much from them. The upper pattern (more likely to be near the mark) allowing for some movement west or east does provide enough uncertainty for our little part of nw europe to make a week 2 call unwise.

[Polar Maritime]

GFS this morning is showing the Atlantic winning out by the 20th, With strong Heights over Greenland pushing Lows on a more Southerly track, Bringing some very wet & unsettled weather from the West.

 

Edited July 13, 2014 by Polar Maritime

[knocker]

The ECM HRES for next weekend has the low pressure edging in from the west. This means the upper flow veering from the south leading to lower temps over the weekend. Friday is very hot with perhaps in the low 30sC in the SE but from then on begins the change.

Edited July 13, 2014 by knocker