Model Output Discussion 18z 28/07/13

[Tamara]

Think you might have it spot on Tamara, particularly about a renewed  NW/SE split,latest UMMO 6-15 certainly thinks so too.

Well they know an awful lot more than me of course!  but I think we are essentially seeing a suggested similar pattern carried forward from August but with seasonal changes just starting to make themselves felt as the jet stream starts to become more active as thermal gradients tighten that little bit - especially further northwards as one might expect

Edited August 29, 2013 by Tamara Road

[Summer Sun]

If you don't mind me being a touch predantic SS, the colours represent height anomalies NOT strictly pressure anomalies at 500mb, the darker the colour the greater the anomaly.

I do agree with your comments about folks arriving and leaving and especially the bit about a cold outlook makes for large page numbers in a short time!

 

Thanks for correcting me, still learning some of these charts

 

[No Balls Like Snow Balls]

The 06 GFS op run was pretty much out on it's own in relation to the Autumnal blast shown on the op from around 5th Sept onwards. Slightly below average but no where near as extreme as op run.

 

 

 

 

 

[bluearmy]

next weeks troughing will continue to cause headaches for the next few runs at least.  just to note that dropping energy just to our sw is a strong naefs spread theme this morning though this could easily be in conjunction with a trough in our vicinity rather than throwing a euro ridge ahead of it. no doubt the flip flop ecm and gem ops are reflecting this uncertainty.

[Milhouse]

A big high over the UK to start the new week on the GFS 12z.

 

Temperatures edging up as well

 

[Buzzit]

I still think we will see a Euro high in situ before we find ourselves in Autumn proper. I think this high can last rather than be routed by Atlantic low pressure

 

[Summer Sun]

Next weeks low isn't as wide spread as on the 06z much smaller now (still deep but further away from the UK as well)

 

 

UKMO also has a big high over the UK early next week

 

 

The high breaks up mid next week but it remains over the SE

 

[Milhouse]

Its looking increasingly likely that our old friend the Azores high doesnt want to depart just yet. It edges in over the weekend and gradually transfers over to the east of the UK by midweek to set up a classic southerly plume. Upper temperatures of 15c just off the south coast in the GFS.

 

[shaky]

What a beautiful set of hot charts from both the ukmo 12z and gfs 12z!! Would not be surprised if the low pressure doesnt make inroads at all and we stick with the current weather pattern!!

[Swave Snow]

What a beautiful set of hot charts from both the ukmo 12z and gfs 12z!! Would not be surprised if the low pressure doesnt make inroads at all and we stick with the current weather pattern!!

 

What about the anomaly charts, are they not suggesting locked in Troughs and the lark with Autumnal weather creeping down south eastwards?  Or are they subject to the same swings as the operationals, I always thought that was the case?  Anyway this is truly and has been an interesting set of confusing signals now for ages.

[Cloud 10]

Do we need a new thread??  91 pages is long....

 

It would be a shame to stop it now so close to the century!

 

Anyone else having problems with Meteociel this evening?

[Summer Sun]

It would be a shame to stop it now so close to the century!

 

Anyone else having problems with Meteociel this evening?

 

Aye its not loading for me either

[draztik]

Speaking of the GEM, it has reverted back to a rather unsettled theme from about t156 to the end of its run, in contrast to the settled conditions it was showing on the 0z output (backend of its run)

http://meteocentre.com/models/compar_models.php?map=eur〈=en&run=12&stn=PNM&&range=glb&hh=168

the gem and gfs 12z at 168 look fairly similar.

Edited August 29, 2013 by draztik

[shaky]

And what an ecm 12z up to 120 hours so far!!things look like getting hot and humid next week!!!woop woop!!

[Captain Shortwave]

T144

 

 

Very warm in the South

The low to the west is much weaker, wonder if it will stall to the west of us as a ridge builds to the east

Or a Greenland high could form *facepalm*

Edited August 29, 2013 by Captain shortwave

[Summer Sun]

Nice and warm to start next week after a fresher feel to this weekend especially overnight

 

 

[Summer Sun]

Low pressure starts to move in at t168 but it remains warm

 

 

Once again ECM has this big area of low pressure back for later next week

 

Edited August 29, 2013 by Summer Sun

[Summer Sun]

Here is the latest summary on the models from Gibby

 

Good evening. Here is the report on the 12 noon outputs from GFS, UKMO, GEM, NAVGEM and ECM for today Thursday August 29th 2013.

 

All models show a series of weak fronts moving SE over the UK with some bursts of light rain in places as they pass. Cloud amounts will be large overall with a moderate Westerly wind blowing and just brief sunny intervals. Over the weekend the troughs clear away with a NW flow bringing cooler and clearer weather across all areas with sunny spells and the odd shower in the North. By Monday and Tuesday pressure builds across the South with some warm sunny intervals developing as winds back towards the SW. In the North cloud and occasional rain will develop as fronts move in from the west on a freshening breeze.

 

GFS then shows a deepening depression up to the NW gradually extending it's influence to all areas with rain or showers before the weekend. The Low then fills as it moves SE over the UK then Europe. Then through the rest of the run a period of slack pressure develops before High pressure builds West over the South for a time at the end of the run with some fine and warm weather in the SouthThe GFS Ensembles are broadly similar to this morning when taken as a whole with a breakdown occurring in the South around the 5th with rain at times for the rest of the run. Temperatures after a few more warm days early next week settle close to average though with some marked fluctuations shown through the second half of the run especially in the South.

 

The Jet Stream shows the flow gradually moving slowly South towards the UK on a West to East pattern although accessing data tonight is rather difficult and this statement is based on the 6z output.

 

UKMO tonight shows High pressure out to the SE with a warm South flow albeit light across the South and east. Out to the West a front is poised to move into the UK late in the day with some rain possible.

 

GEM shows a shift tonight to a decline in conditions later next week as Low pressure sinks South and develops into a deep feature close to the SW by the end of the run. A progressive spell of deteriorating weather would be likely from the middle of next week with showers or longer spells of rain in places as well as increasing winds and cooler conditions.

 

NAVGEM shows falling pressure too from midweek as Low pressure becomes influential to the NE of Britain with a cool Northerly flow developing later next week with showers in the North and East with cool night's.

 

ECM shows Low pressure developing to the NW with a broad trough extending South over the UK with rain and showers developing for all later next week. The end of the run indicates Low pressure in control to the North of the UK with abroad and unstable westerly flow across the UK with rain at times for all in average temperatures at best. 

 

In Summary tonight the trend I alluded to this morning is shown again tonight with the prolonged High pressure based ridge from the Azores over the South showing signs of declining away as the Jet Stream steers Low pressure down over the UK later next week with some useful rain and showers for all. To what extent and duration such a change will take is unsure at the moment but it does look increasingly likely to happen with each run so best enjoy the decent weekend and start to next week while we still can.

 

http://www.norton-radstockweather.co.uk/Model-Analysis%282859336%29.htm

 

 

[Biggin]

GFS 06Z

 

The very warm uppers (12+) manage to hold on in the South East until midweek.

 

gfs-1-150.png

 

 

But by the end of the week Autumn is here. Hmmm sniff sniff, what is that i can smell?, yep that's right fresh, cool autumn air.

 

gfs-1-174.png

Shed n dras will be creaming  emselves at last

[Man With Beard]

HP holding on a little longer on op runs tonight? Could this be one of those situations where a pattern change gets pushed back and eventually watered down? If the low stalls a little west it could be interesting

[Bristawl Si]

HP holding on a little longer on op runs tonight? Could this be one of those situations where a pattern change gets pushed back and eventually watered down? If the low stalls a little west it could be interesting

Yes - especially as some posters on here were expecting cool and unsettled (a few days ago) for the weekend.IMBY looks pretty good.

[bluearmy]

the extended modelling shows the troughing to be a 3 day wonder. that could still get trimmed further or maybe extended. thereafter, heights rebuild again to a degree so no need to be too concerned. (except it seems the worst conditions will be at the weekend )

[Tamara]

The potential dogs breakfast of the modelling from this morning of what happens to the trough next week is reduced a little leaner tonight with the solutions that were present in the EPS members from this morning, amongst the general Heinz 57, of the slower trough and amplified downstream ridge ahead of it (rather than behind) gaining some favour. This would fit in with the general pattern of the second half of the summer and postpone further any autumnal unsettled incursion further south.

 

This is not unexpected and whilst it is also entirely possible they will switch again - the pendulum is already showing signs of keeping with what we have already.

 

And look at the change in the EPS members from this morning for about the same period as shown then. Much more leaner cuisine than fatty scraps   *uff * ...did I ever think I would get to post corny MOD posts 

 

[mushymanrob]

Yes - especially as some posters on here were expecting cool and unsettled (a few days ago) for the weekend.IMBY looks pretty good.

 

..... but thats what the models were showing. blaming posters for commenting on the available data isnt right mate.

 

dont you just love the great british weather?.... the recently progged late august heatwave, modelled by all for a week or more became nothing but a few hours at the last minute.... now we are faced with a mini warm spell (very warm? hot?) that has evolved out of nothing but a transient southerly ridge. the ridge was expected to build in over the weekend, but flatten out after a warm front transits the north introducing muggy westerlies. that ridge is now expected to build into a proper high, and its transit has been slowed down. so what was looking like a couple of muggy, rather overcast (esp in the west) warm but breezy days now looks like being much more settled, with high uppers, in any sun itll be very warm.

[Cecil Hogmanay Melchett]

Charts look great for sunday to wednesday but the bbc 5 dayer for manchster is awful.

what gives??