Model Output Discussion 18z 28/07/13

[Methuselah]

Daddy long-legs. 

You're bloody right, right enough!

[ANYWEATHER]

So lets see what the models have done this afternoon.

Both ECM and GFS have moved next weekends low a couple of hundred of miles north and is now fairly similar to the GFS mean from this morning. Again suggesting the operationals like for most of the summer have tried to place the trough too far south.

ECM has picked up on the GFS signal in the 10-15 day range but like in July it is too quick with the evolution and I expect it to delay until the 21-22nd August.

All in all a good model suite this afternoon. 

Lets address a couple of claims in the thread

For northern washout, here is the total predicted rainfall from the GFS until next Saturday

 

Nothing particularly special, only the highlands and Cumbria are particularly wet which is typical of westerly flows. 10-20mm across northern areas typically, not unusual with bands of light-moderate rain between the drier and warmer spells of next week. Matt Hugo's tweet from yesterday morning stated nationwide wet and below par temperatures for next week which simply is not the case now.

Ah the heatwave scenario. All I am interested in is the trend to bring high pressure in from the 21st onwards which still looks good. Get the heights in and let the heat build.

@anyweather you still don't believe the heatwave last month happened (despite it being the 3rd warmest July on record) 

Mr CS. Listen from me and I enjoy your posts, but there is nothihg in the 10 day output which is of course is unreliable,to suggest any heatwave  

Edited August 10, 2013 by ANYWEATHER

[Captain Shortwave]

Mr CS. Listen from me and I enjoy your posts, but there is nothihg in the 10 day output which is of course is unreliable,to suggest any heatwave  

I was only joking  

I know there isn't, I said there isn't a heatwave shown as of yet. All we can look for is signs of the weather becoming more anticyclonic. which the ecm mean suggests at day 9/10

GFS/ECM at least in the mean sense are starting to sing off the same hymn sheet. 

Increasing confidence of a more high pressure dominated scenario from the 20th August onwards 

Edited August 10, 2013 by Captain shortwave

[ANYWEATHER]

I was only joking  

I know there isn't, I said there isn't a heatwave shown as of yet. All we can look for is signs of the weather becoming more anticyclonic. which the ecm mean suggests at day 9/10

GFS/ECM at least in the mean sense are starting to sing off the same hymn sheet. 

Increasing confidence of a more high pressure dominated scenario from the 20th August onwards 

Looking at the models all I can see is just a normal fest for August! No ex-hurricanes in the equation at the moment to stir things up!!!

[draztik]

I can see that HP is trying to build, and that's all well and good! But, as each day passes, and as we near september the less chance of any real hot weather! Ill take an indian summer tho, with highs in the low to mid 20s!

[johnholmes]

http://www.meteo.psu.edu/~fxg1/ECMWF_12z/test8.gif

 

http://www.cpc.ncep.noaa.gov/products/predictions/814day/814day.03.gif

 

signs of Something getting better.....??

yet again the further south and east you live

I have no idea why those charts prompt you to say that.

The anomaly charts have been pretty consistent in showing a fairly strong w'ly flow acorss the Atlantic into a fairly rounded trough in the UK area.

Do beware of using the anomaly bits, and anyway it is only showing a very small +ve anomaly.

[DTHFCJ]

I have no idea why those charts prompt you to say that.

The anomaly charts have been pretty consistent in showing a fairly strong w'ly flow acorss the Atlantic into a fairly rounded trough in the UK area.

Do beware of using the anomaly bits, and anyway it is only showing a very small +ve anomaly.

i said signs??a very small +ve anomalys a start and the further south and east you are..........

[Weather Boy]

The phrase 'knife edge' has been used a fair bit recently, and I agree with that.......

 

.......but which side of the knife you are likely to find yourself surely depends on how far south you are.

 

As I understand it, all models are agreed on HP to the south, LP to the north.  The disagreement is where these pressure areas are centred.  Is it near or even north of Iceland, allowing all of the UK, barring perhaps northern Scotland at least at times, to share in the settled and reasonably warm weather or, to take the other extreme, are we talking about a brisk westerly flow with all apart from perhaps the SW and south coast to be in a showery unsettled theme with frontal systems at times?  The two are not a great synpotic shift apart, making the answer very hard to discern at this point.

 

However, one thing the models seem agreed on is that it's HP south and LP north, meaning that whatever happens south to be better than north.  Where the dividing line, if there is one, is very unclear though: somewhere between highlands of Scotland (most optimistic) to somewhere somewhat to the south of Paris (most pessimistic) seems likely.

 

South is best on pretty much any scenario, though!

[Bristawl Si]

Looks like "more of the same" to me

.

[draztik]

Not sure what to make of the gfs 18z! It has the low concentrated over Iceland at the weekend, but it then becomes stubborn to move. The HP in FI is all but gone,

t300

this is how the gfs 18z ends its run, with the Atlantic becoming far more mobile..

as opposed to hp from its earlier run (gfs 12z)

as for the talk of a heatwave, ... This chart asks us, heatwave? Where?

Edited August 10, 2013 by draztik

[bluearmy]

having been away for a week, my initial view of the nwp is that things are looking average to decent for the next fortnight, especially the further southeast in the uk you find yourself.  week 2 looking particularly interesting as heights may well rise from the se.

[draztik]

The MetO is differing with the other main models this morning at the end of its run! it has a deep area of low pressure just west of N.I. at t144

this will need to be watched!

ecm at t144!

Edited August 11, 2013 by draztik

[The Northern Ramper]

The Gfs,ECM and Gem all delay the low next weekend and send it further north allowing heights to build from the south, excellent agreement from these models.

The Ukmo at 144 has it 200 miles further south and 24 hours earlier, it looks like a 144 wobble but as ever let's wait and hope it is not a trend.

In general, positive by the models this morning.

[mushymanrob]

good morning guys...

 

sometimes its good to ignore the runs for a day then come back with a fresher perspective...

 

gotta say.... congratulations to the gfs, its picked up on a hot spell well into fi, and although its far, very far, from 'in the bag' there is growing support that it could happen in 8+ days time.

 

if it was going to happen, it would start to show on the anomalies... and this morning (yesterdays)

 

there it is... a chart run by itself means nothing, but if it gets support today/tomorrow then chances of it becoming reality increase markedly. as i see it, its the first tentetive step towards a late aug hot spell. it needs varification, but the gfs still suggests heat, the ecm @ t240 also agrees with the gfs's evolution, so is suggest there are good signes ahead that we MIGHT just get the best august summery spell (for more then the southeast) for ten years.

 

before then, we have a nice day today, cooler fresher showery (but not greatly) mon tues, warmer by weds but cloudier and rather muggy i suspect. a deep low expected next weekend should bring a breezy/windy spell with some rain. thats then expected to migrate north, and pressure expected to rise from the south... then, hopefully, a hot spell!

 

so a pretty 'normal' week ahead, followed by a more unseasonal couple of days, before possible hot spell from c8 days away.

[mushymanrob]

as for the talk of a heatwave, ... This chart asks us, heatwave? Where? 

 

here

 

here

 

and here

 

all these charts have a very similar evolution to t240, these charts are all t240, the anomaly and gfs build the pressure/heat beyond t240, the ecm doesnt go beyond t240 but with a similar evolution theres good support this morning that by t240 we should be on the cusp of a decent hot spell, one for a large section of the country and not just the southeast.

 

its NOT in the bag... but with good cross model support like this id suggest something similar is likely to happen, the exact detail, timing etc may be uncertain though.

[draztik]

I hear you Mushy! But i was commenting on the gfs 18z, which wasn't showing what you just posted! In saying that, your charts don't look overly hot! Certainly not akin to July! The anomaly charts would need to change for me to believe this was about to become a uk wide event, rather than a SE spell!

[shedhead]

Well for those looking for a straw to clutch Mushy has provided one, but if we were now in the middle of a heatwave and someone was posting charts showing a return to cooler, more unsettled weather in 10 days time I'm pretty sure many would highlight (and that is putting it politely!) the folly of looking so far forward. As things stand the next week or so is expected to see an increasingly stark NW/SE split, with many parts of England and Wales enjoying pleasant late Summer weather, whilst Scotland and N Ireland flirt with far more Autumnal conditions at times, especially if the ECM is to be believed. Not ruling out another heatwave as we move into the final week or so of August, but it's a very long way from being nailed at the moment...again as Mushy pointed out. 

[Frosty.]

Things are looking better and better on this morning's Gfs 00z, for a start, next weekend was looking cool and unsettled on yesterday's output but today the models are looking considerably better with the PFJ further to the northwest, from wednesday the temperatures are into the mid 20's celsius, initially just in the southeast but as time goes on, the warmth in the southeast spreads out further north and west as high pressure builds to the southeast, it turns into a nw-se split, the northwest of the uk more unsettled but with sunnier and warmer days here and there but the southeastern half of england becomes very warm for a while, there is then a brief cooler and unsettled blip the following week before the azores/atlantic anticyclone builds in again, even stronger with a nationwide settled spell towards the end of the month and potentially hot with the 564 dam line pushing up from the continent.

[ANYWEATHER]

To be honest, I really cant see anything screaming heatwave conditions at all in the recent output. Ok  very warm conditions flirt with the south in picticular at times but washed down with cooler air at times. Normal August weather, and indeed nice conditions for many I would think  

[TootyFruity]

Morning Frosty

Any news on the weather for Scarborough ?

The models seem to be flirting with the idea of warmth coming albeit slowly up the country , but I'm sure I saw in the newspaper yesterday that wednesday we were going to get a real dumping of rain and I think SSun posted a few charts to correspond with that !!

Thankyou

Tooty

[Frosty.]

Morning Frosty

Any news on the weather for Scarborough ?

The models seem to be flirting with the idea of warmth coming albeit slowly up the country , but I'm sure I saw in the newspaper yesterday that wednesday we were going to get a real dumping of rain and I think SSun posted a few charts to correspond with that !!

Thankyou

Tooty

Hiya,

 

It looks like sunshine and showers tootyfruity, go prepared for showers, whatever the weather, hope you have a nice holiday in scarborough.

[bluearmy]

heatwave? i see no sign yet of a real 'heatwave'.  becoming more settled over time though with the following caveat - shallow troughs moving west to east cannot be discounted (as looks to be the case next weekend). the anomoly, building initially from the se then seems to become established to the east/northeast thru week 2. that then allows for temps to build but currently the spreads out to two weeks not showing this. week 2 maxes 26/27 in the south and dropping slowly as you head north. if we do get a decent block to our east then clearly that allows for a whole gammut of scenarios including thundery incursions form the sw. certainly a decent outlook considering there was plenty of doom and gloom painted once the july spell had ended.

[Jax]

I think for some July was quite extreme so the August output may well appear benign for but is in fact quite good for the time of year, and in the past I am sure it would be taken as decent honest summer conditions.

[draztik]

Gfs 6z only reinforces my earlier thoughts. Absolutely no sign of a uk wide hot spell on the way!

gfs ends its run with

about sums up August so far! Average.

Edited August 11, 2013 by draztik

[Frosty.]

I think most of you will agree that the Ecm 00z ensemble mean is trending towards a fine and warm last 10 days to august, it looks really promising to me and has support, bring it on.