Model Output Discussions 12z 03/05/2016

[Man With Beard]

I'm a bit too nervous to confidently call next week one way or the other - we've now seen numerous runs pulling the trough a little further north or shifting it a little further south - with somewhere in the UK being on the dividing line between the settled stuff and the unsettled stuff. 

The ECM seems to have had the fewest fluctuations in recent days - less eye candy on the ECM for next week, but interestingly a good trend even here - notice how the main trough gets slightly further NW on each run, and how heights over Greenland get eroded bit by bit as we move towards T0 (now when have we heard that before when reviewing the ECM!)

    

Knocker - a note on something you said last night - I agree it's preferable to post charts as evidence but sometimes I post "on the run" and I judge it better just to make some contribution to the thread even without a chart, rather than make none at all. I presume the mods do not mind this?

[phil nw.]

1 hour ago, Man With Beard said:

I'm a bit too nervous to confidently call next week one way or the other - we've now seen numerous runs pulling the trough a little further north or shifting it a little further south - with somewhere in the UK being on the dividing line between the settled stuff and the unsettled stuff. 

The ECM seems to have had the fewest fluctuations in recent days - less eye candy on the ECM for next week, but interestingly a good trend even here - notice how the main trough gets slightly further NW on each run, and how heights over Greenland get eroded bit by bit as we move towards T0 (now when have we heard that before when reviewing the ECM!)

    

Knocker - a note on something you said last night - I agree it's preferable to post charts as evidence but sometimes I post "on the run" and I judge it better just to make some contribution to the thread even without a chart, rather than make none at all. I presume the mods do not mind this?

No problem MWB there's no hard and fast rules on the way to post.It is preferable to support a post with charts or some other relevant data but as long as the content reflects the outputs then there should be no issue.

Just looking at the gefs 00z ens the message clearly now is a gradual return to our more usual Summer weather as the notable heat of this week gradually erodes away.

The Azores high still of some influence from time to time but looking more inclined to extend eastward towards France rather than southern UK in the coming 10 days.The Icelandic trough omni-present to the north having more of a say with associated fronts moving across the UK from time as a weaker Summer jet  again tracks across the UK over the coming couple of weeks.

The mean charts for days 5 and 10

A look at the ens graphs for 2 locations to illustrate the somewhat north/south differences in temperature and rainfall-one in Argyle and the other Sussex.

Clearly not a great amount of rainfall expected over the next 2 weeks,even in the less favoured north west,and looking quite dry in the south indicating that many of the fronts look like weakening as they come south into the higher mean pressure over the southern UK and N.France.

Temperatures though do like returning towards normal and compared to recently will feel a lot fresher but there still looks to be some decent weather to come when the sun does come out.

 

Edited July 22, 2016 by phil nw.

[stodge]

Morning all

The GFS 06Z suite is roiling out at present so it may all look very different (or it may not).

To be honest, the 00Z OP runs don't look much different from those of Thursday.

GFS remains the most bullish for a continuation of settled conditions especially across the south with the Azores HP ridge persisting longest and strongest and only really breaking down at the end of next week which, to be fair, has been long and consistently forecast by successive OP runs at 00Z:

This time next week and it's pretty much game over:

Interesting to see the trough already moving east so a more mobile pattern with the jet close to or over the north of the British Isles.

ECM not too different at the same time:

GEM rather worse and still keeping an echo of the idea from earlier in the week of a possible mid-Atlantic ridge though there's just enough energy in the Atlantic to prevent its development which is welcome:

All in all, a gradual deterioration to more unsettled conditions during next week with temperatures returning to average and rainfall amounts gradually increasing away from the NW which looks in for a disappointing week I fear.

Further ahead into August and there are plenty of options on the table - as ever, more runs are needed.

[knocker]

The trough would appear to becoming more dominant towards the end of the ten day period but this is probably the normal fluctuation as it weakens again in the later period but the pattern is essentially the same. The challenge here is to find different ways of saying the same thing.

Edited July 22, 2016 by knocker

[northwestsnow]

Not a great 06z has to be said, more trough influence as we struggle to see the high build in.

More runs needed but the trend on 6z is not a good one if its summer weather you want further down the line with the jet sinking south again..

Edited July 22, 2016 by northwestsnow

[coldcomfort]

6 minutes ago, knocker said:

The trough would appear to becoming more dominant towards the end of the ten day period but this is probably the normal fluctuation as it weakens again in the later period but the pattern is essentially the same. The challenge here is to find different ways of saying the same thing.

Indeed, the 06 franks this very well in the post T+168 range, with what can only be described as a pretty dire period to come around the turn on the month. Indeed the size, depth and persistence of the toughing looks very ugly post 240hrs and IF it verifies even close to whats shown we can definitely write off week one of August and fear significantly for week two also imo. Really not what most of us want to see, especially when we're still awaiting the start of summer! 

[mb018538]

The 6z is a horror story and should come with an 18 certificate! Not for young eyes to see!! 

Hoping for the 12z set to revert back to something more akin to last nights 12z, with the trough still present, just at arms length for many leading to ok conditions.

[cheeky_monkey]

Lots of greens and blues on the charts later in the run which must be somewhat unusual for early August.?..looks more like late September synoptics

[northwestsnow]

55 minutes ago, coldcomfort said:

Indeed, the 06 franks this very well in the post T+168 range, with what can only be described as a pretty dire period to come around the turn on the month. Indeed the size, depth and persistence of the toughing looks very ugly post 240hrs and IF it verifies even close to whats shown we can definitely write off week one of August and fear significantly for week two also imo. Really not what most of us want to see, especially when we're still awaiting the start of summer! 

Well that's got me utterly baffled! Its been a lovely week as far north as manchester and probably for longer down south, unless you class temps in the low to high 20's as Autumn i got no idea what you mean..

Edited July 22, 2016 by northwestsnow

[William of Walworth]

I'm sceptical (OK no doubt also hopecasting!) that late next week is definitely set to be just like those 06z runs are showing. Fluctuations in positioning and detail still perfectly possible between now and next weekend. More runs needed as ever, and I'd be surprised, (sticking my neck out), if some future output doesn't show soime improvements, with a possible NWwards retreat of trough,  as well as more trough dominated turns. It;'s the all too frequently seen uphill and downhill way.

 

I'll be interested to see what the latest are showing next Monday, after my imminent pleasant-weather weekend away near Bristol. (Near term forecasts for that area still looking broadly nice for tonight, Sat, Sunday morning)

[Summer Sun]

Looking at UKMO the north and north west is likely to see some cloud and light rain at times whilst further south and east it should be brighter and warmer

The Jet stream is forecast to be very weak next week so not a great deal happening with regards to rain just dribs and drabs mainly for the north

Edited July 22, 2016 by Summer Sun

[northwestsnow]

http://old.wetterzentrale.de/pics/Rukm961.html

http://old.wetterzentrale.de/pics/Rukm1201.html

http://old.wetterzentrale.de/pics/Rukm1441.html

I would hazard a guess the first two charts on ukmo are generally fine and warm across England - on the third pressure is falling and would be showery for most i suspect.

Either way, while looking better than GFS (not difficult), it would seem by the last chart trouble is waiting in the wings,or in this case,the Atlantic..

Edited July 22, 2016 by northwestsnow

[Man With Beard]

GEM joins UKMO in keeping pressure higher than GFS for midweek.

It's still difficult to read this one, but I'm prepared to guess than southern areas will see virtually nil rainfall before the end of next week at least, some sunny spells and temps in low to mid 20s - not bad really (high 20s tomorrow and Sunday). Northern areas clearly cooler and showery, but not a washout even here I suspect. REMEMBER! After T84, the GFS goes precipitation mad - don't trust it until inside this timeframe.

Keep watching for a possible plume over France by the end of the week and for signs that it may get further north IF forecasts of our main trough moving south are wrong...

Edited July 22, 2016 by Man With Beard

[mb018538]

By the looks of things, by next weekend, we will be well and truly under trough influence...not desperately unsettled with the weak Jetstream, just average summer weather.

[knocker]

A pretty dry run with temps varying around the average next week Not bad -could be a lot worse

[phil nw.]

A snapshot of the 2m temps expected on day 4 early afternoon our time.

which typifies our Summer climate really.Continental heat extending again into high latitudes ie.N.Scandinavia/Russia.The UK somewhat cooler on the seaboard of Europe partially under the influence of the cooler uppers from the Icelandic trough.

This appears to be the general pattern as we go into next week lasting for a while.As Knocker said not too bad, somewhat cooler but with little rainfall being modeled especially further south.

 

[Captain Shortwave]

Looking at the GFS/UKMO/ECM at days 5 and 6

      

      

 

The GFS is very different with the parent low to our north cut off with drier conditions in the south with temperatures a little on the cool side, the Euros and indeed the GEM show a stronger jet upstream with another low developing to our west which in turn forces a weak ridge NE through the south of the UK and into northern Europe, this is a pretty typical set up with a broad warm sector affecting many areas with temperatures potentially rising into the very warm category in the south on Wednesday and Thursday before this low clears eastwards. Neither are particularly wet, though the Euros offer a rise in temperatures again midweek whilst the GFS keeps temperatures around or a little below normal throughout next week.

Edited July 22, 2016 by Captain Shortwave

[Matthew.]

For any finding the warm humid/cloudy conditions too much there's good news early next week from the consensus as fresher Atlantic air comes in. In contrast with winter though this doesn't guarantee anywhere near the crisp sunshine one might expect. An Atlantic wind direction is notorious for cloudy conditions, even PM in Summer, as the general pattern shows no signs of change just yet. 

Edited July 22, 2016 by Matthew Wilson

[Matthew.]

The ECM 12z for Friday/Saturday next week A 2 day event thankfully before westerlies presume as normal.

[knocker]

No change with the anomalies this evening. The only chink of light that I can see is the EPS does have the trough weakening and moving east with the Azores HP ridging more towards the end of the ext period. A scenario supported by the recent EC32 for the same period.

 

[mb018538]

Not looking too sharp is it? Plenty of disagreement where the exact location of the trough will be, but it's looking increasingly likely the rest of July and first week of August are for the trash can. I'm off to California for a fortnight on the 15th, so couldn't give a monkeys what the second half of August holds! 

[knocker]

The weekend

Mainly dry for all with some rain moving into the NW later. Very warm in the east and quite pleasant elsewhere.

Next week with this morning's GFS. After brief ridging effecting the south at the beginning of the week the rest is unsettled with an area of low pressure to the north and north east and other lows winging in from the west and phasing in with this general area bringing periods of rain to most. Temps around average.

[knocker]

Although varying in detail the ecm is similar to GFS in becoming unsettled nest week. Just one chart to sum it up.

 

[fine wine]

Very much a continuation of weather we have seen for the last 7 days with anyone from a line from say the Humber to Bristol seeing warm settled conditions (23-25c) and those further northwest seeing more influence from the week trough to the north west. As we have seen generally seen the settled conditions have actually been more widespread than the models have been suggesting with this weekend being a fine example I suspect that this may continue with the trough digging south West next weekend to give us another shot at hot weather. Out of interest; what was originally described as 2 or 3 warm days has tuned out to be 7 continuous days hot and sunny weathe between 25c and 31c here in Essex

Edited July 23, 2016 by fine wine

[northwestsnow]

2 minutes ago, knocker said:

Although varying in detail the ecm is similar to GFS in becoming unsettled nest week. Just one chart to sum it up.

 

Quote

 

Yes, looking increasingly unsettled as we head through next week knocker, no disagreement from me there!

http://old.wetterzentrale.de/pics/Recm2401.html

Does look like heights are breaking down to the North west at day 10 on ecm but thats a long way away so just a hope for now.:)