Model Output Discussion 18z 28/07/13

[J10]

Unfortunately Saturday but camping over night into Sunday midday.I'm just glued to this page but its like watching a foreign movie .................. Without subtitles lol

 

If only the quality of the dialogue matched that of the Renevants. Given the rain forecast over the next few days some places will look like that town as well.

[Severe Siberian icy blast]

The ECM is quite consistent now in its FI output of troughing developing over Iberia, beforehand that separate high cell off the Azores high edges ne, a similar set up occurred before that hot weather last week for the UK.The interest really comes as to where this troughing sets up if it verifies, this will decide whether its heatwave part 2 or just a hot blip.I'd be wary of the outputs showing a quick ejection ene of this troughing as we had much the same suggestion in FI before and as we've seen the models were far too progressive.I think the GFS in its FI looks a bit more likely with the trough ejecting more ne/n, generally I'm happy to ignore the lower resolution GFS but when you're in very much a stalemate pattern its normally the default recent synoptics that seems most likely.Theres no real catalyst here for a major change over Europe, the MJO signal is weak and until that changes then a big change over Europe is unlikely, within this stalemate though is pinning down the detail which is a difficult job because of the big differences felt on the ground depending on where exactly any troughing sets up, a couple of hundred miles either way which is tiny on a global level will make a big difference.

Couldn't agree more, when the MJO is weak it can do little to change the weather pattern , even if it moves to a different phase , it doesn't mean it will become the driver , with Europe scorching this year more than ever , just like stubborn fridged air in the winter , it can be very hard to shift , if we can have low pressure toward Iberia , a ridge over us , and low pressure toward Iceland , we can hit the jackpot in terms of sunny weather . If its storms you want , then if its positioned right , with a long feed of southerly air coming up the eastern side of the low pressure , we will experience hot , muggy , and thundery weather.I love both to be honest , it beats cool and wet summers we normally have . What a summer , Iv been on netweather more or less every day this summer , my mrs thought I was only like this in the winter !! Gullible fool!!!

[William of Walworth]

I'm somewhat fearful from the latest range of output that we'll end up at frequent risk of storms and downpours in what looks like some pretty serious heat in coming days and into next week. This especially concerns me for the w/e around Friday9th/Saturday 10th August, but thankfully we're still too early to be certain.

 

Us festival goers prefer stable HP driven warmth rather than hugely unstable heat ...

Edited July 29, 2013 by William of Walworth

[DTHFCJ]

http://176.31.229.228/modeles/gens/naefs/run/naefs-0-0-48.png?12

http://176.31.229.228/modeles/gens/naefs/run/naefs-0-0-72.png?12

http://176.31.229.228/modeles/gens/naefs/run/naefs-0-0-96.png?12

http://176.31.229.228/modeles/gens/naefs/run/naefs-0-0-120.png?12

http://176.31.229.228/modeles/gens/naefs/run/naefs-0-0-144.png?12

http://176.31.229.228/modeles/gens/naefs/run/naefs-0-0-168.png?12

http://176.31.229.228/modeles/gens/naefs/run/naefs-0-0-192.png?12

 

NAEFS not looking too bad either

edit the further south and east you are.......

Edited July 29, 2013 by BALE1

[Nick F]

Yes, upper flow looking very sluggish and meridional across the Atlantic on the ECM and GFS as we head into early August and it seems the models are backing away from introducing a more progressive and zonal flow across NW Europe. For once, the UK is ending up on the warm side of the slow-moving amplified trough which seems intent on hanging out just west and NW of the UK.

 

A strong block stretching from the central Med up across central Europe seems to be helping keep back cooler conditions from regaining control across the UK, so unless a strong jet powers up across the Atlantic, it seems we will continue to see more plumes of heat moving up from the continent over the coming 7 days and perhaps beyond. With it, a continued risk of storms at times too, as colder air moves in aloft from the west at times above the very warm and humid air.

Edited July 29, 2013 by Nick F

[mushymanrob]

this chart shouldnt be taken out of context, until others agree and the patterns shown for several runs its not overly accurate, but it does show the first signes of something possibly hot and thundery IF im interpreting it correctly...

 

which adds support for the ops , esp the gfs (which spotted the repeating plume pattern first), for a southerly/thundery pattern... oh it should be pretty warm/hot too at times, but atm theres no lengthy hot spell.

[johnholmes]

yes great care always with these type of charts and especially as this is at odds with both its previous pattern and those predicted on NOAA for both 6-10 and 8-14 at the moment

[Scorcher]

Does anybody know what's happened to the ECM on Wetterzentrale? It seems to have gone haywire. I saw the run up to 72 hrs as it was coming out and it now appears to be showing completely different charts. Have a look at what happens to the 850 hPa temperatures at 144 hrs!

[johnholmes]

just to show how unsteady the 500mb anomaly outputs are at the moment, the output this morning from ECMWF-GFS

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

 

GFS does keep some suggestion of +ve height anomalies across the trough but ec has done away with that idea this morning.

I would be very wary of suggesting anything is clear cut beyond 6-8 days at the moment. But as Nick F has posted there is no real sign of the Atlantic powering up to any extent. Any prediction with a slack flow at upper level is bound to switch about a bit and the precise position of the upper trough is of course vital in terms the flow being off the continent (=heat) or more oceanic (=less heat).

Edited July 30, 2013 by johnholmes

[Djdazzle]

Does anybody know what's happened to the ECM on Wetterzentrale? It seems to have gone haywire. I saw the run up to 72 hrs as it was coming out and it now appears to be showing completely different charts. Have a look at what happens to the 850 hPa temperatures at 144 hrs!

I notice that too. Very odd.

[Nick F]

just to show how unsteady the 500mb anomaly outputs are at the moment, the output this morning from ECMWF-GFS

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

 

Not sure I agree entirely that the 500mb pattern is unsteady as you say (unless I'm reading you wrong) - certainly IMO in the 6-8 days ahead, the models and ens mean seem to agree on a sluggush trough/ridge pattern over the N Atlantic/Europe with a mean trough stalling out W and SW and strong blocking high re-establishing over central Med and central Europe. However, as has been the case for a while now, the models keep wanting to introduce a more mobile and zonal Atlantic regime beyond 8 days, yet the every run we get closer the zonal return seems to be put back to that range.

[Frank Trough]

Quite big differences between the GFS and UKMO at t+144:

 

 

UKMO makes much less of the trough to our southwest, and from what i can tell from Meteociel is much more similar to the ECM:

 

 

The ECM then seems to wander off into a bit of non-descript but gradually cooler pattern which seems to reflect the thoughts from the met office.

 

Interesting model watching, though.

[Captain Shortwave]

Rather fun and also frustrating model watching at the moment. ECM after quite a few runs building a strong ridge to the east simply decides to bulldoze the ridge at day 5. Really baffling how it can swing and change even quite close to verification. It then proceeds to fall off a cliff with a rather slack pattern which looks very unlikely to come to fruition. 

GFS looks the more reliable scenario, especially given ensemble support and that it was the route models have been taking up to now.

Not to bash models but I feel the UKMO has been performing very poorly recently. Definitely the most easterly biased of the models at the moment as seems to not like the weak jet at all. Example of this is wanting to breakdown this weeks plume a day earlier than most models and last Saturdays trough which even at T48 had this low 100 miles too far east and was against all other model output.

[Frosty.]

In the short term, the Ecm 00z op run has upgraded the hot plume for friday over a wider area with a thundery breakdown then pressure rises during the weekend and although the heat and humidity levels drop, it stays warm and becomes more settled for a time into next week but then a risk of slow moving, heavy and thundery showers within a very sluggish slack pattern for most of next week, only the far north flirts with cool north atlantic air from time to time, the south remains warm or very warm at times throughout.

[Lincstim]

Morning folks. Any change for this Saturday?

Even waking up after a night shift (finishing at 6am) at this time all because of the bloody weather forecast for Saturday and the fear its going to be a wash out!

You can tell I don't get out much lol

[johnholmes]

Not sure I agree entirely that the 500mb pattern is unsteady as you say (unless I'm reading you wrong) - certainly IMO in the 6-8 days ahead, the models and ens mean seem to agree on a sluggush trough/ridge pattern over the N Atlantic/Europe with a mean trough stalling out W and SW and strong blocking high re-establishing over central Med and central Europe. However, as has been the case for a while now, the models keep wanting to introduce a more mobile and zonal Atlantic regime beyond 8 days, yet the every run we get closer the zonal return seems to be put back to that range.

these are the notes I made this morning about ec-gfs, I make these notes every day around this time and update them every day after I have looked at the noaa output in the evening.

To an extent yes I would agree that it is a sluggish upper air pattern at times on one or other of them. Beyond that then there are enough differences in my view watching them closely every day to be uncertain just what the pattern will evolve into.

 

Tue 30 julyTue 30 july

Ec-gfs

Ec this morning has dropped the idea of a +ve height across the trough which they both showed yesterday, gfs keeps it, so a different idea from ec, neither are very similar to the noaa ouput either for the same period that is 6-10 days or the later outlook at 8-14.

Until all 3 show consistency with themselves and one another for 2 preferrably 3 days then not much confidence can be placed in the actual upper air pattern in my view.

Edited July 30, 2013 by johnholmes

[Summer Sun]

Has ECM has gone haywire at t144 and t168? that heat looks severe across Spain, Portugal and southern France if it hasn't even southern England would be in the 30s with +15 uppers

 

Edited July 30, 2013 by Summer Sun

[johnholmes]

Not sure I agree entirely that the 500mb pattern is unsteady as you say (unless I'm reading you wrong) - certainly IMO in the 6-8 days ahead, the models and ens mean seem to agree on a sluggush trough/ridge pattern over the N Atlantic/Europe with a mean trough stalling out W and SW and strong blocking high re-establishing over central Med and central Europe. However, as has been the case for a while now, the models keep wanting to introduce a more mobile and zonal Atlantic regime beyond 8 days, yet the every run we get closer the zonal return seems to be put back to that range.

I think consistent would have been a better word to describe them Nick?

[Bobby]

It seems to me there will be more high pressure about but it doesn't look anywhere near as robust and 'clean' as it did earlier in the month. They are troughs and little lows often circling about in the charts I've been seeing. And the models have never shown a persistent spell of anticyclonic weather with the GFS FI and the anomaly maps being consistent in showing a fairly zonal flow into the middle part of August.

 

Of course plenty of uncertainty looking this far out but that seems the most likely to me given the consistency. A pressure and temperature rise for a few days, with rain, probably mainly convective, at times, before a transition to more active westerly weather. NAEFS has been consistent in showing LP anomalies into middle August for a while now. ECM ensemble mean at +240 shows the more westerly regime also

 

 

 

[Frosty.]

The Ecm 00z ensemble mean looks good to me, a hot sultry plume thurs/fri and risk of storms on friday which may linger in the far east/se into saturday, then becoming fresher & fine and remaining on the warm side with high pressure developing, so a few fine days later in the weekend and into next week, then pressure falls a bit and the pressure pattern looks very sluggish next week, the atlantic looks benign so next week would probably be warm and showery with sunny periods and light winds, some of the showers becoming heavy, thundery and slow moving with humidity levels rising again, especially across the south, seeing the atlantic so quiet is good news as our temperatures should continue at least slightly above average and generally rather warm or very warm. 

[shedhead]

Once again I think too much emphasis is being given to heat across the next 7-10 days, with the period still appearing a bit mixed at least to me.  Temps look pretty average today and tomorrow, clearly Thursday is going to be very warm, locally hot for many, but even by Friday values look closer to average in the west. Any lingering warmth/heat across central and eastern areas on Friday gets sweep away overnight, with most of the country seeing close to average temps over the weekend, though the SE may become rather warm.

 

Into next week the jury is still out imo, but temps should be on the warm side for most, at least on Mon/Tue. Pressure may well build for a time across eastern areas in particular, but the west will probably remain perilously close to the mean trough, so precisely where that sets up will dictate whether we get another shot at some proper warmth/heat.

 

Edit: The 06 GFS continues to support LP drifting up from France next week in the still very slack overall flow, so IF correct the heat again looks set to build from the south, but clearly it's not long before everything goes BANG once more! Interesting times for sure. 

Edited July 30, 2013 by shedhead

[kev238]

Surely the point is that temperatures of twenty three or so are extremely pleasant and will feel warm in the sunshine; average or slightly above in august are pleasant conditions.

[Timmytour]

I'm off to Cornwall for a week on saturday and getting a little bit more optimistic than i was a couple of days ago for my prospects.

The rain today seems to have pushed a fair way past north of the M4 corridor which is where the extent of it was progged to be a couple of days ago as i recall.  This to me indicates that the models are struggling a little bit with, and underplaying as a result, the northern extent of each push of warm air up from the south.

I'm thinking that, if this is a trend, then the plume set for later this week will be more extensive than currently being modelled and make greater inroads....and likewise with a subsequent build of high pressure over the country.

I might end up getting lucky with the warmth, sunny periods  and a couple of thunderstorms thrown in to boot!

That's my completely unbiased view of things anyway
 

[Tim Bland]

Excellent GFS 06z. Plume Thurs-Fri followed by Storms. Then hotting up again Mon / Tues followed by more storms!   2 hot days and a thunderstorm is a British summer.. This year we are being spoilt!

 

 

 

Edited July 30, 2013 by Tim Bland

[Summer Sun]

2 very obvious plums on the London ensemble this afternoon one this Thursday and Friday the 2nd mid next week

 

 

Elsewhere we have above or average uppers taking us to mid August