Model Output Discussion - Mid Summer Onwards

[Addicks Fan 1981]

54 minutes ago, RainAllNight said:

Speaking of heights over the Labrador Sea, the regular ECM and GEM ensembles, plus the EC46, are showing more interest in these again for later next week. Could we end up with another trough trapped over us?

Last six EC46 runs for the week 11th-18th September, starting with today's (showing mean Z500 anomaly):

The ECMWF hovmoller looked reasonable enough tonight by this link below.   

Time-longitudes diagram - Extended range forecast

CHARTS.ECMWF.INT

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This is a time/longitude diagram (Hovmoller diagram) of 500 hPa or 1000 hPa mean height anomaly (contours) and spread (shading). The mean anomalies are derived from the ECMWF extended...

 

[Cheshire Freeze]

57 minutes ago, RainAllNight said:

Speaking of heights over the Labrador Sea, the regular ECM and GEM ensembles, plus the EC46, are showing more interest in these again for later next week. Could we end up with another trough trapped over us?

Last six EC46 runs for the week 11th-18th September, starting with today's (showing mean Z500 anomaly):

The GEFS are generally supportive of a trough setting in around mid month...which seems about right to me. Probably not cool though as we look likely to be on the eastern side of the mean troughing. Potentially a few wet episodes though.

[Addicks Fan 1981]

31 minutes ago, Cheshire Freeze said:

The GEFS are generally supportive of a trough setting in around mid month...which seems about right to me. Probably not cool though as we look likely to be on the eastern side of the mean troughing. Potentially a few wet episodes though.

The NOAA anomolies are broadly supportive of that scenario, by this image below at 8-14 days time .

[Derecho]

12 minutes ago, Addicks Fan 1981 said:

The NOAA anomolies are broadly supportive of that scenario, by this image below at 8-14 days time .

That looks like a thundery setup to me and warm, specially if we get a trough a bit further west.

Reminds me of the thundery week of early September last year.

[Cheshire Freeze]

GFS trending wetter and wetter into the mid range now

Potential for some hefty rainfall totals if we get into a pattern where we repeatedly draw warmer air up preceding the fronts

GEM also looking very wet this morning

Edited September 7, 2023 by Cheshire Freeze

[seb]

3 subsequent GFS runs plus 1 ECM thrown in, all with very different solutions. Enough said.

Midnight Saturday 16 Sep on GFS 12z, 18z and 00z as well as ECM 18z below.

Even picking noon on Wednesday 13 Sep gives similarly differing solutions. 
 

So as we were. After near record or record daytime and most definitely nighttime temps we are likely looking at something more normal from around Tuesday, although still above average temps and below average rain (possibly some exceptions in the far NW) and generally drier and warmer the further SE you are. No washout, nothing cold, no strong winds and most definitely nothing autumnal (away from the far NW where what’s currently shown is normal).

 

[seb]

To add to my previous post, let’s throw in the 00z ECM for the same time and the low to the NW of the UK has vanished.

[Rain All Night]

Might this tropical storm shake things up again mid-month?

Edited September 7, 2023 by RainAllNight

[mb018538]

UKV suggesting that the weekend will perhaps be the peak of the heat - but with 32c yesterday, it may be a close run thing. The predicted temps on Sunday look like a 33c may be possible somewhere from Cambs up towards the Wash.

ARPEGE takes it a notch further. 34c around Kent/Sussex on Saturday and 33c in similar spots on Sunday.

[Mike Poole]

11 minutes ago, RainAllNight said:

Might this tropical storm shake things up again mid-month?

Yes, I was going to mention that, differences in how that feature is modelled may well affect the broader pattern by T240.  Still far too early to call any kind of return to unsettled, I think, there’s plenty of uncertainty…

[johnholmes]

So looking 6-14 days ahead using my usual models NOAA and ECMWF

By Thursday 7th how are things shaping up, NOAA and ECMWF?

The broad scale pattern on NOAA show a rounded trough, close or just over the UK, with not very high contour values, fairly strong; height 570 DM over the border area.. not very settled I would suggest and certainly no major heat, either side of normal from day to day.

ECMWF starting 6 days from now=13 th, so about the same period as the 6-10 NOAA. It shows a fairly similar pattern with a 500 trough just west or just over western UK through the 6 day period out to Sunday 17 th. The 850 temperatures are below 10C over the whole UK, with the 5 C as far south as south Wales to the Wash for the first couple of days and never further north than the Scottish border in the period.

Overall then, consistency over the past few days by both models, and both suggesting markedly cooler for many than we currently have, also rain or showers at times, this probably on a NW-SE split in terms of frequency as surface features skirt nw of the far north west

Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

I should add, as several others have, Tropical storms may have an influence through this period and neither of these models normally show any signal for this.

Edited September 7, 2023 by johnholmes

[alexisj9]

50 minutes ago, RainAllNight said:

Might this tropical storm shake things up again mid-month?

Depends where it goes I guess, hopefully not towards Portugal again.

[ANYWEATHER]

1 hour ago, RainAllNight said:

Might this tropical storm shake things up again mid-month?

The chances of this happening like this are practically zero.........

[Rain All Night]

1 hour ago, ANYWEATHER said:

The chances of this happening like this are practically zero.........

Well indeed, but all models agree the storm will form in the reliable timeframe, and it has to go somewhere, meaning there is a possibility of it eventually having some effect on our weather pattern

[ANYWEATHER]

12 minutes ago, RainAllNight said:

Well indeed, but all models agree the storm will form in the reliable timeframe, and it has to go somewhere, meaning there is a possibility of it eventually having some effect on our weather pattern

Yes ex tropical storms often have influence on the UKs weather ,just as the last storm did ,which gave us this heat, it could be next time we get a full blown Autumn gale. ...and sometimes these storms ,can dissapate, with no noteworthy weather across the UK. 

Edited September 7, 2023 by ANYWEATHER

[legion_quest]

4 hours ago, seb said:

3 subsequent GFS runs plus 1 ECM thrown in, all with very different solutions. Enough said.

Midnight Saturday 16 Sep on GFS 12z, 18z and 00z as well as ECM 18z below.

Even picking noon on Wednesday 13 Sep gives similarly differing solutions. 
 

So as we were. After near record or record daytime and most definitely nighttime temps we are likely looking at something more normal from around Tuesday, although still above average temps and below average rain (possibly some exceptions in the far NW) and generally drier and warmer the further SE you are. No washout, nothing cold, no strong winds and most definitely nothing autumnal (away from the far NW where what’s currently shown is normal).

 

That sounds like very definite language. I thought we weren't supposed to do that?  

[MattStoke]

3 minutes ago, legion_quest said:

That sounds like very definite language. I thought we weren't supposed to do that?  

They did include the word 'likely' which allows for some doubt.

[legion_quest]

1 minute ago, MattStoke said:

They did include the word 'likely' which allows for some doubt.

Couple of 'definitelys' in there though...hard to measure doubt with a definitely.

[alexisj9]

13 minutes ago, legion_quest said:

That sounds like very definite language. I thought we weren't supposed to do that?  

Night time record went last night so it is definite.

[seb]

28 minutes ago, MattStoke said:

They did include the word 'likely' which allows for some doubt.

Indeed. Language matters

25 minutes ago, legion_quest said:

Couple of 'definitelys' in there though...hard to measure doubt with a definitely.

"After near record or record daytime and most definitely nighttime temps we are likely looking at something more normal from around Tuesday, although still above average temps and below average rain (possibly some exceptions in the far NW) and generally drier and warmer the further SE you are. No washout, nothing cold, no strong winds and most definitely nothing autumnal (away from the far NW where what’s currently shown is normal)."

Where appropriate... The first instance is based on the fact that at least three MetO owned sites exceeded the previous September record this morning and of course also the unprecedented duration of the period where a tropical night is occurring at least somewhere in the country during this current heatwave; the second is because there is no chance of what would be considered autumnal weather during the period to the end of the GFS run.

Edited September 7, 2023 by seb

[legion_quest]

It was only poking fun, hence the winky face. Do try and have some fun from time to time, might make the day even brighter! 

[alexisj9]

5 minutes ago, legion_quest said:

It was only poking fun, hence the winky face. Do try and have some fun from time to time, might make the day even brighter! 

Sorry didn't notice the smiley 

[Captain Shortwave]

Some of the global models have just mixed out the highest 850s a touch for the weekend, as such temperatures tending to be similar to what are seeing now (essentially 50/50 to whether we exceed the highest maxima this year).

GFS

  
 

The ECM operational was also down a degree or so this morning (raw maxima of 29c compared to 31c on the last couple of runs).

Arpege 06z still has maxima of around 33c (possibly 34c) for both days of the weekend. It would be nice to see this figure reached to cap off this spell of weather before we welcome in more seasonal weather and probably sign off for hot weather this year.

[seb]

42 minutes ago, legion_quest said:

It was only poking fun, hence the winky face. Do try and have some fun from time to time, might make the day even brighter! 

Always having fun. Sitting in the sun with a cocktail, taking a break from work

[sheikhy]

55 minutes ago, Captain Shortwave said:

Some of the global models have just mixed out the highest 850s a touch for the weekend, as such temperatures tending to be similar to what are seeing now (essentially 50/50 to whether we exceed the highest maxima this year).

GFS

  
 

The ECM operational was also down a degree or so this morning (raw maxima of 29c compared to 31c on the last couple of runs).

Arpege 06z still has maxima of around 33c (possibly 34c) for both days of the weekend. It would be nice to see this figure reached to cap off this spell of weather before we welcome in more seasonal weather and probably sign off for hot weather this year.

I think we should easily beat the previous max for this year over the next few days!!but to beat  35 degrees now that i dont see happening but you never know!!!!