Model Output Discussion - 1st June 2015 12z--------->

[Methuselah]

NAVGEM 06z showing 2m temps at 38 on July 1st

 

Though I cannae see anything like those temps materializing, I don't one single below-average day in the GFS 06Z. I don't think I've ever seen that before. January not included!

[karlos1983]

NAVGEM 06z showing 2m temps at 38 on July 1st

 

 

I'm going to say, although great charts and possibly not the most reliable source, I really hope that does not happen. Sleeping could be somewhat difficult. 

 

at 2am .....

Edited June 26, 2015 by karlos1983

[stodge]

My first chance to comment for a number of days - the NAO has gone negative and is forecast to stay negative:

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/nao.sprd2.gif

 

That would suggest lower heights to the south-west and higher heights to the north and north-east so the draw of winds (as suggested by the 6Z) may be more SE'ly than S'ly which would have some effect on the synoptics and the weather. However, there's plenty of scatter beyond next weekend so none of this is a done deal yet.

 

http://modeles.meteociel.fr/modeles/gfs/runs/2015062606/gfs-0-132.png?6

 

This is a seriously interesting chart for storm fans and there's plenty of heat about to make things happen.

 

http://www.meteociel.fr/modeles/ecmwf/runs/2015062600/ECM1-144.GIF?26-12

 

But this is subtly different. Events out to the east make a difference as the Scandinavian HP is further west so everything else is further west.

 

http://modeles.meteociel.fr/modeles/gem/runs/2015062600/gem-0-144.png?00

 

GEM very close to GFS in the same timeframe - possibly less of a heat fest (though marginal) and more of a storm fest.

 

Plenty of time though for things to chop and change but I do think the last 24 hours has seen a move away from a direct S'ly feed from France and Iberia to a more SE'ly feed from Europe - still hot but the potential for more disturbed weather has risen.

[knocker]

Cornwall downgraded yet again. On the other hand........

Chart weatherbell

 

[Nick L]

NAVGEM is a cannon fodder model for a reason. Fun to look at though.

[Harsh Climate]

What record HC?

plumes > 20c are very rare in the UK. it is obviously not sustainable for several days so we look to those runs which shorten the plume to 24/36 hours max as being more likely to be showing a verifiable solution.

ECM fi looks progressive though the sinking of the scuero high anomoly south west to become a euro high anomoly is the favoured extended ens option so a more standard zonal flow north of the UK should be the eventual outcome.

 

What record do ya think..

 

The maximum temperature record for July somewhere in the north of england. Based soley on that output though, so yes only retrospective at this stage.

[seaside 60]

NAVGEM is a cannon fodder model for a reason. Fun to look at though.

I must admit it has to top the most stupid charts.

Surely at times like this is needs to be remodeled.

I will of course eat my words if Norwich does reach 42c.......and not in someones greenhouse...

[bluearmy]

What record do ya think..

 

The maximum temperature record for July somewhere in the north of england. Based soley on that output though, so yes only retrospective at this stage.

Clearly single date temp records for specified places could fall but the July temp record for England? Nope - not with the predicted set up this time.

[stodge]

Of course we had a significant July heatwave as long ago as 2013 for those who'd forgotten:

 

http://modeles.meteociel.fr/modeles/gfs/archives/gfs-2013072000-1-66.png?0

 

On 22nd July 2013 a temperature of 33.5c was recorded at Heathrow Airport and not far away at Northolt.

 

GFS forecast temperature for Wednesday next week:

 

http://modeles2.meteociel.fr/modeles_gfs/runs/2015062606/132-582UK.GIF?26-6

 

One of the things we will need to see is the heat being embedded - this is the first significant plume or plume-like event of the year and we've had mostly cooler air over us for some time so the immediate arrival of heat won't have the impact it would have were the heat to be already in situ.

 

This is why the hottest temperatures come not in the inital heat outbreak but in the second or third wave - a hot June peaks in early July and as we saw in 2003, a hot July peaks in early August.

 

http://modeles.meteociel.fr/modeles/gfs/archives/gfs-2013072900-1-90.png?0

 

This gave us 34.1c in London. 850HPAs are or can be misleading - what fans of heat will want to see is the heat become established and wait for second or third waves from the south. It's actually the same process as works with the cold in winter if you think about it.

[Man With Beard]

Clearly single date temp records for specified places could fall but the July temp record for England? Nope - not with the predicted set up this time.

You cannot possibly be that confident! Its still not out of the question that we'll end up with 3 days under the 20C 850 line, and sunshine amounts / exact direction of flow cannot be predicted yet! 33-35C is the likely benchmark, but 36C is absolutely not out of the question. Yet!

[Harsh Climate]

Clearly single date temp records for specified places could fall but the July temp record for England? Nope - not with the predicted set up this time.

 

Lol where did I say the maximum temperature record for england would be broken, obviously that is most unlikely 

[Tamara]

Atmospheric fluctuations, which occur through subseasonal variations related to (ocean) SST boundary forcings and (atmosphere) mid latitude merdional momentum transport and mountain torques, are comprised as measurements of those fluctuations within the tropical (Madden Julian Oscillation) and extra tropical (Global Wind Oscillation). These changes manifest themselves in key weather events that can have a profound effect on weather patterns over a large part of the globe.

 

It is in this context that the recent transitional period from a La Nina type atmospheric imprint on weather patterns over the winter and spring has been of particular interest in recent weeks - and especially anticipating the effects of the changes on the likely direction on NWP during the early summer.

 

From my own point of view, it has not failed to disappoint - and continues to provide a separate additional focus of great interest and fascination to looking out for favourite weather type(s) in the model output

 

Recent posts have discussed detail about how the oceanic/atmospheric relationship has changed decisively from the winter and spring - with large westerly wind additions to the atmosphere which have created positive frictional torques and associated large Mountain torque - as depicted by current Phase 5 Global Wind Oscillation orbit.

 

http://www.atmos.albany.edu/student/nschiral/research/gwo/gfsgwo_1.png

 

*Further explanations about phase spaces and the torque mechanisms associated with Atmospheric and Angular Momentum follow below the links*.

 

The effect of these forcings on Atmospheric and Angular Momentum tendency has been very significant in its upwards trend, to an extent not seen for many, many months

 

http://www.atmos.albany.edu/student/nschiral/research/gwo/gfs1.png

 

The yellow hatched areas clearly depict the westerly wind additions across the tropics - in association with resultant positive frictional torque and associated mountain torque which trigger the subsequent upswing in AAM tendency itself

 

Those westerly wind additions are reflected in the MJO plots - with agreement in the models for increasing amplitude towards Phase 6/7  - always a sign of Nino atmospheric imprint

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/ECMF_phase_51m_small.gif

 

GFS forecasts a little slower back in Phase 6, but same overall trend of increasing amplitude with eastward moving convection. Based on forward projections, into July, pressure anomalies will be much better matched than presently suggested

 

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/NCPE_BC_phase_21m_small.gif

 

The importance attached here, is the increase in amplitude in these particular phases - in direct contrast to the low AAM/Nina like imprint of winter and Spring - which showed easterly wind additions firing from convection originating in the Indian Ocean. That was always a signal for the MJO to beat a retreat from MJO Phase 7 and implying convective forcing on weather patterns dying before progressing to the Nino imprint of the central and Eastern Pacific

 

*To further try and explain the complex dynamics here*  

 

The additions of westerly energy across the tropics (a positive frictional torque) have to be compensated elsewhere as Mother Nature will not allow a vacuum. These frictional (earth/ocean) torques created through westerly wind burst momentum (WWB) are compensated northwards at mid latitudes (typically 30 to 40 N) by eastward moving atmospheric momentum - i.e represented higher up as a mountain torque event. It is in this way that Atmospheric Angular Momentum balances itself - and the measure of change to achieve atmospheric equilibrium is represented as AAM tendency. In the case of westerly wind bursts it is upward (+ve) tendency

 

These tropical/extra tropical events are forcing factors behind the mechanisms discussed in the very informative detailed post given by Vorticity last night - in terms of the meridional Atmospheric and Anglular momentum transport processes that has set the amplification pattern in motion as he described his own way - and which, in relation to its effects in our relevant sector of the Northern Hemisphere, lead to the enhanced Tropical Continental airstream next week, and associated burst of heat over UK and Europe

 

Anticipating model synoptic evolution can be assisted through understanding how these atmospheric events impact global weather patterns.

 

*Where do the relevance of the Phase plots come into the equation?*

 

The key events (in terms of physics) that occur in atmospheric and tropical convection episodes help to identify associated model synoptic patterns that occur in reponse to those events - and these are given 'Phase spaces' to plot MJO/GWO orbit. It therefore becomes possible to match synoptic patterns to the anticipated phase space(s) according to orbit behaviour

 

Downstream of the Asian mountain torque, energy is added to the jet stream over the Western Pacific. This fully supports the (above linked) GEFS forecast of GWO orbit into a higher amplitude Phase 6/7. Not seen for quite some time since a muted attempt in early Spring

 

Further downstream, this has further knock on effect synoptically and supports the persistence of an Atlantic upper trough and Euro ridge scenario. As some of the upstream energy follows downstream it is reasonable to expect some, relative, flattening of the amplification, but with maintenance of a Euro mid latitude ridge. A less hot interval may follow at this time, and the greatest intensity of the plume is moved east - but with the atmospheric state now displaced as described and a large hot air source nearby (much as many would hope for the opposite in winter time) it will take very little further amplification to trigger a reload of the heat.

 

Initial thoughts in previous posts about a pattern change to a proper warming summer trend espoused 10 days and more back have really accelerated faster than originally anticipated. The measure of the latest ECM London ensembles really emphasise this perspective, with the anticipated relatively 'less hot' interval represented after the weekend of the 4th/5th looking like the sort of return drop we saw just a few weeks back as commonplace......

 

...Except that the drop is to levels still at or above the 20C benchmark (as the coolest!)

 

http://www.weathercast.co.uk/meteo/eps/ensemble-tt6-london.gif

Edited June 26, 2015 by Tamara

[summer blizzard]

Models seem to be in agreement but have actually made the warmth last a bit longer. Wednesday-Saturday could see 30C breached however Friday see's a thundery front move through the UK before a second (likely more normal) front moves through by day 9. 

 

[Frosty.]

The GEFS 6z mean is looking fantastic next week..and beyond, becoming very warm across all parts of the UK and hot across the south and east as a spanish plume extends northwards into the uk. There is talk of very hot conditions developing in the south / southeast with low to mid 30's celsius. With all the strong sunshine, heat and humidity, there will be an increasing chance of thundery showers.

We have waited patiently for this, we have had to endure a lot of cool unsettled atlantic dross in the last few months but the wait is almost over.

[Methuselah]

You cannot possibly be that confident! Its still not out of the question that we'll end up with 3 days under the 20C 850 line, and sunshine amounts / exact direction of flow cannot be predicted yet! 33-35C is the likely benchmark, but 36C is absolutely not out of the question. Yet!

Especially if next week's temps are being undercooked, like today's clearly have been...

[knocker]

The current MJO running from phase 6 to 7 doesn't seem a good fit for our current  500mb anomaly

[Mapantz]

In these situations, the 850's can become detached from what happens at the surface, it's also possible that the temperatures are being overcooked, even with those sorts of uppers being projected.

[bluearmy]

You cannot possibly be that confident!

I can and I am

 

Lol where did I say the maximum temperature record for england would be broken, obviously that is most unlikely 

You didn't HC. Someone else did and I dealt with both posts together - I could have been clearer though.

[Summer Sun]

GFS sending the hot air further north on this run! 06z on the right

 

[95 Degrees]

You cannot possibly be that confident! Its still not out of the question that we'll end up with 3 days under the 20C 850 line, and sunshine amounts / exact direction of flow cannot be predicted yet! 33-35C is the likely benchmark, but 36C is absolutely not out of the question. Yet!

 

Well GFS 12z brings back the possibility of that happening, more inline with the 0z so far 

 

[Summer Sun]

GFS keeps showing some very hot conditions widely on Thursday

 

 

If you want to escape the heat go to either Cornwall, Isle of Man, Abderdeenshire or the western Isles

 

Before that its Monday when the heat starts in the south and it keeps on rising

 

Edited June 26, 2015 by Summer Sun

[mhielte]

Still very warm/hot on Saturday on the GFS 12z. So potentially 4 straight days of 30C+ on this run.

 

 

The Atlantic making no inroads to break it down at all. It's scenarios like this that could see records broken with a more sustained period of heat.

[Captain Shortwave]

Day 6 charts

Hot with temperatures into the low thirties widely (Including as far north as Glasgow), a heatwave begins in earnest with the low thirties forecast on Friday and Saturday too under a hot south easterly wind.

 

UKMO

Very similar to the GFS, perhaps showing the potential for some thunderstorms to push up from France, that said I suspect hot and sunny weather would return beyond this point as the ridge tightens its grip as the Atlantic runs out of steam.

Of course this will change time and time again, I suspect we won't break the July record yet, but the highest temperature this decade is up for grabs I feel.

[shaky]

Unbelievabley hot gfs and ukmo this afternoon!!this could seriously be newsworthy heat next week!!the agreement between gfs and ukmo aswell is astonishing!!!

[Summer Sun]

GFS gives the potential for 30c 5 days running next week

 

 

Forget downgrades....we're getting upgrades!!!

Edited June 26, 2015 by Summer Sun