Model Output Discussion 06Z, 13 Sep. 2013 ---->

[Frosty.]

frosty I hate to spoil your summer party but you are getting a touch OTT in my view in your interpretation of how high temperatures are going to be, from whatever model you quote.

I simply cannot see that values will approach the 'hot' category for the 3rd week in September as you suggest nor do I see the temperatures actually reaching, other than in isolated spots where good cloud breaks occur, the values you quote.

I am trying to be objective.

Hi John, I can see lots of potential in those charts I posted, in years gone by, 80F has been known in early october and just taking the ecm 00z ensemble mean charts I posted as a prime example, the synoptics look choc full of potential for mid 20's celsius next week. I don't like disagreeing with you because you are an expert but i'm just saying what I think based on these type of charts in previous years and I consider mid 20's c to be hot by late september standards, warm  bordering on very warm by summer standards.

Edited September 20, 2013 by Frosty.

[Scorcher]

Exactly scorcher, to the east of high ground looks best with clouds breaking to allow longer sunny spells and temps into the 70's F, then mid to high 70's F next week with increasing amounts of sunshine, looks great to be honest.

 

Whatever happens with the cloud, it will feel warm and the temperatures will hold up well into the evening and at night- should be a very pleasant spell regardless of cloud amounts.

[Tamara]

the MJO also doesnt suggest a sustained settled spell.  We have been in (weak) phase 5 since around 15th September and forecast to move through to phase 6.  10-12 day lag brings us to the end of next week to see something more benign before turning more unsettled into first week of october?

 

Phase 5 and 6 sept mjo.jpg

Yes, getting back to the topic, the latest MJO ensemble forecast (yesterday) was tentative and very sluggish about progression to phase 6. Hence just one reason for a lot of care needed in terms of extrapolating model movements and pattern changes. Caution therefore advisable about how quickly the settled pattern might break down with time - I think, f.e, that the ECM this morning may have responded to this over progression

 

[Frosty.]

Whatever happens with the cloud, it will feel warm and the temperatures will hold up well into the evening and at night- should be a very pleasant spell regardless of cloud amounts.

I may be alone in thinking this, perhaps you will agree scorcher, but I think although this settled spell will start rather cloudy, there will be less cloud and more sunshine by sunday and even sunnier next week, and the uk covered in very warm uppers (T850 hPa) it would only stay supressed in the low 20's c if there is continuing rather cloudy conditions next week which I don't think will happen, it will be nice to look back on this upcoming summery spell and see how warm it actually got in favoured areas, like heathrow airport for example.

[Scorcher]

The ECM chart for Monday doesn't look particularly cloudy to me for most- then again perhaps someone can explain in more depth but we've definitely picked up less of a southwesterly and more of a southerly by that point by the looks of things. As you say we don't need unbroken sunshine with the warm 850 hPa temps.

[Frosty.]

The ECM chart for Monday doesn't look particularly cloudy to me for most- then again perhaps someone can explain in more depth but we've definitely picked up less of a southwesterly and more of a southerly by that point by the looks of things. As you say we don't need unbroken sunshine with the warm 850 hPa temps.

I may be wrong, probably am actually but I think drier continental air from due south or a touch southeast is on the cards next week with clearer, sunnier skies rather than a continuation of the moister cloudier sw'ly tropical maritime airflow which we initially get tomorrow and sunday, temps on sunday in any sunny spells as high as 21-22c, probably the southeast and east being the warmest spots on sunday, rather cloudier and less warm further west/nw...just my opinion

Edited September 20, 2013 by Frosty.

[mushymanrob]

A Chilly FI from GFS. Temps taking a tumble to Oct average.

 

 

 

with respect, since when was the early average for october 'chilly'?..

 

 

Hi Mushy-  I have never not once - EVER used those charts-  Waste of time mate-  because they incorporate the super Ensemble mean- which is often similar to your name. - MUSH

 

 

 

 

 

steve... well  john holms does. his 3 year study found that theres a (impressive) 70% accuracy rate when the main 3 agree for 3 or more runs. he does say they are little use when they dont agree, me? im learning, but so far am begining to grasp what john and others have already discovered. but that accuracy rate 6-10 days ahead isnt one that should be ignored imho.

 

apart from that, theres no one data set that is the holy graille, we chose which to use either by ease of understanding, or because its prone to show what we would like to see. what we need is a replacement for gp... unbiased, uses all the data available, who interprets it accurately.

 

Frosty I'm afraid your temps are way out . Again . You search and search for the holy grail in every model , but they fail to materialise mostly .

 

.... and in a couple of weeks time he will be batting for cold... will you be so keen to criticise when hes searching for the coldest option? will you be so keen to criticise others who do? or is it just 'non cold' that cannot be persued vigourously?

 

well the 00z ecm and 06z gfs arent bad are they! they have reduced the 'chilly' bit next week, which highlights one thing... the models are finding hard to grasp the exact pattern to emerge post tuesday. until then, ill enjoy the warmth.

[No Balls Like Snow Balls]

with respect, since when was the early average for october 'chilly'?..

 

 

 

steve... well  john holms does. his 3 year study found that theres a (impressive) 70% accuracy rate when the main 3 agree for 3 or more runs. he does say they are little use when they dont agree, me? im learning, but so far am begining to grasp what john and others have already discovered. but that accuracy rate 6-10 days ahead isnt one that should be ignored imho.

 

apart from that, theres no one data set that is the holy graille, we chose which to use either by ease of understanding, or because its prone to show what we would like to see. what we need is a replacement for gp... unbiased, uses all the data available, who interprets it accurately.

 

 

.... and in a couple of weeks time he will be batting for cold... will you be so keen to criticise when hes searching for the coldest option? will you be so keen to criticise others who do? or is it just 'non cold' that cannot be persued vigourously?

 

well the 00z ecm and 06z gfs arent bad are they! they have reduced the 'chilly' bit next week, which highlights one thing... the models are finding hard to grasp the exact pattern to emerge post tuesday. until then, ill enjoy the warmth.

 

One mans chilly is another mans warm. Bit pointless asking really as you will get hundreds of different answers depending on the type of person you are. To me it felt god dam chilly earlier in the week in the wind and rain.

You seem to have it in for everyone thats not pursuing or believing in crazy pie in the sky warmth in this post lol

Edited September 20, 2013 by No balls like Snow Balls

[Suburban Streamer]

Yes, getting back to the topic, the latest MJO ensemble forecast (yesterday) was tentative and very sluggish about progression to phase 6. Hence just one reason for a lot of care needed in terms of extrapolating model movements and pattern changes. Caution therefore advisable about how quickly the settled pattern might break down with time - I think, f.e, that the ECM this morning may have responded to this over progression

 

agreed Tamara

 

Also perhaps worth noting that in phases 5-8 the Ukmo verifies the best (and phases 1-4 the ecm verifies best)

 

that info from here: http://www.mri-jma.go.jp/Dep/cl/endo/paper/paper_5.pdf

 

Edited September 20, 2013 by Suburban Streamer

[Frosty.]

On the face of it, these fax charts look excellent, the 564 dam line is across northern scotland on monday and there are no fronts near the uk, the breeze appears to be from a very warm continental source, south of east, by tuesday, a subtle change, the orientation of the anticyclone changes but the 564 dam line is still across southern uk, a weak front drifting down across the far north but high pressure still in control, I would say tuesday will be even warmer than monday in the south but on the flip side, northern areas will be cooler by tuesday but mainly fine with sunny spells apart from the rather cloudier weak frontal zone, although even along the front, the cloud band should fragment as it dissolves when it pushes further into the high.

[Captain Shortwave]

Lets add a little bit to the GFS 06Z

The control is better than the op, the cooler air struggles in during Friday to all areas

The Mean well this sums it up nicely

 

Northern areas have a flow sourced from northern Scandinavia, the South have a flow sourced from North Africa.

Looks like a riddle wrapped in a mystery inside of an enigma. 

Edited September 20, 2013 by Captain shortwave

[Scorcher]

One mans chilly is another mans warm. Bit pointless asking really as you will get hundreds of different answers depending on the type of person you are. To me it felt god dam chilly earlier in the week in the wind and rain.

You seem to have it in for everyone thats not pursuing or believing in crazy pie in the sky warmth in this post lol

 

To call average 'chilly' at the beginning of October is slightly misleading though. By all accounts 'chilly' implies something lower than the average. If you are implying that it might 'feel chilly' then to be honest that is very subjective and we don't know the finer details of the weather that far ahead. If the cooler (average) temperatures occur, who's to say it won't be 15C with sunshine and little wind at this stage?

[bluearmy]

  because they incorporate the super Ensemble mean-

 

.

 

S

 

only at 'automated weekends' steve and during the week, only if the forecaster decides to use it in his blend of input. (which i assume means it looks reliable wrt the other output).  i would say the super ens mean is used less than any other model in my experience of reading the prognostic discussion.

[No Balls Like Snow Balls]

To call average 'chilly' at the beginning of October is slightly misleading though. By all accounts 'chilly' implies something lower than the average. If you are implying that it might 'feel chilly' then to be honest that is very subjective and we don't know the finer details of the weather that far ahead. If the cooler (average) temperatures occur, who's to say it won't be 15C with sunshine and little wind at this stage?

 

To be honest I don't think anyone actually cares about our ramblings about whats chilly or not chilly.

It's just the word I choose to use to describe the FI part of the GFS run. If people want to disect the word chilly then please go ahead but i really cant be bothered to get involved.

Edited September 20, 2013 by No balls like Snow Balls

[Frosty.]

Feel free to disagree (I got my tin hat on just in case)  but I happen to think this Ecm 00z operational run looks exceptionally good for this time of year, superb actually, becoming very warm for this time of year, and yes i'm using that hot word again for the south, these are fantastic charts by september (late september) standards. Another thing, this ecm run is much better than the 12z last night with the cool unsettled weather sliding by to the east of the uk with high pressure continuing to boss our weather all through next week and beyond, although it does eventually become somewhat cooler, the south holds on to very warm weather for around a week or so, i'm no expert but I do know good charts when I see them.

Edited September 20, 2013 by Frosty.

[MR EXTREMES]

To be honest I don't think anyone actually cares about our ramblings about whats chilly or not chilly.It's just the word I choose to use to describe the FI part of the GFS run. If people want to disect the word chilly then please go ahead but i really cant be bothered to get involved.

Indeed chilly would be the word I'd use considering we have temps in the low to mid 20s next week.But certain no 30c will be breached infact mid twenties will be the max but still very nice for mid Sept which is nothing exceptional,The nao and ao is forcast to dip below average or futher still.But intresting seeing high latitude blocking popping up but bit to soon for my liking but who knows could this be the start of an exciting winter I hope so.All we need now is low sun inactivity and nice powerful Canadian warming event and nice strong strat warming event to stop the full formation of the polar vortex then game on.Good seeing the models showing a change to a more unsettled cooler outlook glad its not going to stay to hot for to long no October heatwave likely.

[Summer Sun]

Late taste of summer anyone?

 

 

 

Thanks to netweather's FB page for the pic

[Scorcher]

Late taste of summer anyone?

 

 

 

Thanks to netweather's FB page for the pic

 

Monday looks pretty cloud free for most us if that's to be believed!

[seabreeze86]

Monday looks pretty cloud free for most us if that's to be believed!

I think your reading the charts wrong, white means cloud and dark means clear, at least that the case on the HIRLAM model.

 

Just noticed that chart was from the NMM my mistake

Edited September 20, 2013 by seabreeze86

[Frosty.]

I think your reading the charts wrong, white means cloud and dark means clear, at least that the case on the HIRLAM model.

 

Just noticed that chart was from the NMM my mistake

I agree with scorcher about monday being sunnier, whatever the chart shows, I think it will be sunnier than the weekend, no fronts near the uk on monday, 564 dam line near northern scotland, if that's not very warm I will eat my hat, it also looks similar on tues,wed and thursday at least and becoming very warm for the time of year...nice

Edited September 20, 2013 by Frosty.

[Captain Shortwave]

At 3 days into the run and the GFS is already disagreeing with it's previous run. 

 

UKMO looks similar to the 06Z GFS run, the energy is mostly going south east

So UKMO and GFS disagree at just 3 days out. 

Day 4 - Not even going to bother. I literally give up.

Edited September 20, 2013 by Captain shortwave

[mushymanrob]

One mans chilly is another mans warm. Bit pointless asking really as you will get hundreds of different answers depending on the type of person you are. To me it felt god dam chilly earlier in the week in the wind and rain.

You seem to have it in for everyone thats not pursuing or believing in crazy pie in the sky warmth in this post lol

 

indeed i agree that earlier in the week it was chilly in the wind and rain.......... but thats not whats predicted 'as temps tumble', its going from well above average, warm, down gradually towards average in largely settled anticyclonic conditions. chilly mornings? yes, but not afternoons.

 

au contraire, ive been accused of being overly pessimistic all summer as i didnt buy into the ramping of temps.. like your doing here, i was putting an overly negetive spin on things..... i was wrong...

 

the point is that the models over the next week or so, currently dont suggest either 'hot' nor 'chilly' daytime max's.

[Summer Sun]

High pressure is back this afternoon on GFS

 

 

A slow process to colder uppers this afternoon

 

Edited September 20, 2013 by Summer Sun

[Summer Sun]

UKMO is wreaking the high pressure this afternoon

 

 

Meanwhile GFS is much slower this afternoon for bringing in cooler uppers

 

 

Big delay on the cooler uppers this afternoon

 

 

Cooler uppers are way out at t312 this afternoon

 

 

Warmer uppers back at t360

 

 

Not much blocking around either to end GFS

 

Edited September 20, 2013 by Summer Sun

[johnholmes]

Hi Mushy-  I have never not once - EVER used those charts-  Waste of time mate-  because they incorporate the super Ensemble mean- which is often similar to your name. - MUSH

 

 

 

S

an odd comment to make Steve. I thought I had proved over a 2 years test that, with the provisos I always give that they give an accuracy of 70% for the upper air pattern 6-15 days ahead. I ask you to show me anything which gives that degree of accuracy in the synoptic outputs or from any other source that you and I are able to access on the web?