Model Output Discussion - Mid Summer Onwards

[Metwatch]

2 hours ago, Uncertainty said:

What does now seem likely is a deep low passing either through or just south of the U.K. on Wednesday.

Wonder if that low will trend a bit more south and slide through the channel, could mean some parts of Midlands and northwards stay drier next Tuesday / Wednesday. 

[northwestsnow]

12z mean isn't great.

Clearly we are looking at the 3rd week for hope,perhaps Azores high ?

 

Edited July 29, 2023 by northwestsnow

[Addicks Fan 1981]

9 minutes ago, Metwatch said:

Wonder if that low will trend a bit more south and slide through the channel, could mean some parts of Midlands and northwards stay drier next Tuesday / Wednesday. 

Must say that I will take the ensemble mean charts with more dignity than I will with the op charts as things are currently.   At the moment ECMWF deterministic runs are looking at a dartboard low but will that scenario be backed on the ensemble mean? Which is why I think that more information for me needs to be looked at.    

[Uncertainty]

8 minutes ago, Metwatch said:

Wonder if that low will trend a bit more south and slide through the channel, could mean some parts of Midlands and northwards stay drier next Tuesday / Wednesday. 

 

Doesn’t look that way tonight pal, I’d be less surprised if it deepened further and thus took a more northerly track through central areas. If agreement there on Monday morning the warnings will start coming out. If it wriggles away from the developmental part of the jet then it wouldn’t develop as much and would go south, but seems the less likely option tonight.

I don’t like el ninos personally, especially with this Atlantic SST profile, you just end up with a seemingly relentless spawning of Atlantic lows right at us. Reminds me of august 19 - Feb 20 where they just kept coming week after week. Hopefully we get a breather mid/late August.

[Addicks Fan 1981]

2 minutes ago, northwestsnow said:

12z mean isn't great.

Clearly we are looking at the 3rd week for hope,perhaps Azores high ?

 

However the mean chart doesn't really back the dartboard low scenario, however the Greenland highs need to drop and stronger highs over Scandinavia need to develop.   Odd summer really what we are in.    

[I remember Atlantic 252]

36 minutes ago, Metwatch said:

Wonder if that low will trend a bit more south and slide through the channel, could mean some parts of Midlands and northwards stay drier next Tuesday / Wednesday. 

wishful thinking but thinking Wed is a write off, EC showing it now too, wasn't there on 00Z

[Metwatch]

2 minutes ago, I remember Atlantic 252 said:

wishful thinking but thinking Wed is a write off, EC showing it now too, wasn't there on 00Z

Could also be quite convective, sunshine and showers don't mind that. 

[Cheshire Freeze]

29 minutes ago, Uncertainty said:

 

Doesn’t look that way tonight pal, I’d be less surprised if it deepened further and thus took a more northerly track through central areas. If agreement there on Monday morning the warnings will start coming out. If it wriggles away from the developmental part of the jet then it wouldn’t develop as much and would go south, but seems the less likely option tonight.

I don’t like el ninos personally, especially with this Atlantic SST profile, you just end up with a seemingly relentless spawning of Atlantic lows right at us. Reminds me of august 19 - Feb 20 where they just kept coming week after week. Hopefully we get a breather mid/late August.

Yes, if anything these systems get pushed further N during summer as T0 approaches

[Rain All Night]

On 19/07/2023 at 22:49, RainAllNight said:

If anyone fancies something new to look at (I've had a quick search and don't think anyone's posted this on here yet), the ECMWF website now shows the deterministic outputs from a couple of machine learning models.

Analysis at 12z today:

ECM operational, two machine learning outputs, and ECM ensemble mean, all showing 500mb heights at T+240h (12z on Saturday 29th July):

Links to the above charts:

https://charts.ecmwf.int/products/medium-uv-z?base_time=202307191200&level=500&projection=opencharts_north_atlantic&valid_time=202307291200
https://charts.ecmwf.int/products/fourcast_medium-uv-z?base_time=202307191200&level=500&projection=opencharts_north_atlantic&valid_time=202307291200
https://charts.ecmwf.int/products/pangu_medium-uv-z?base_time=202307191200&level=500&projection=opencharts_north_atlantic&valid_time=202307291200
https://charts.ecmwf.int/products/medium-t500-mean-spread?base_time=202307191200&projection=opencharts_north_atlantic&valid_time=202307291200

There is a bit of background about the machine learning models here on vedur.is (which you will want to translate unless you can read Icelandic):

https://www-vedur-is.translate.goog/um-vi/frettir/rannsoknir-benda-til-thess-ad-notkun-gervigreindar-geti-aukid-nakvaemni-i-vedurspam?_x_tr_sl=is&_x_tr_tl=en&_x_tr_hl=en&_x_tr_pto=sc

Just for fun, as a follow up to my above post 10 days ago, here is the 12z analysis for today. It looks like "PANGU" is our winner this time:

Edited July 29, 2023 by RainAllNight

[ANYWEATHER]

Ecm ,with the  green blob    no, upper level low on day ten .......

Edited July 29, 2023 by ANYWEATHER

[Addicks Fan 1981]

9 minutes ago, RainAllNight said:

Just for fun, as a follow up to my above post 10 days ago, here is the 12z analysis for today. It looks like "PANGU" is our winner this time:

Just looked at the NOAA 8-14 day chart anomoly and the mean trough does seem present still, but the mean trough to me doesn't look as vigorous as it did before or has done on previous runs, very similar to the ECM 00Z ensemble this morning actually.   

Climate Prediction Center - 8-14 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

[Snowyowl9]

AH some straw clutching desperate if I m looking at 2 years ago..

What a mess whats happened to this summer,wheres the jet dived off to here..

[TheOgre]

14 minutes ago, Snowyowl9 said:

AH some straw clutching desperate if I m looking at 2 years ago..

Edited July 29, 2023 by TheOgre
I don’t know how to type after quote.

[NorthSeaCloud]

15 minutes ago, Snowyowl9 said:

AH some straw clutching desperate if I m looking at 2 years ago..

I remember that spell of weather. Awful North Sea cloud Wednesday 25th onwards. You’d look at that chart and think the country is in wall to wall sunshine.

[mushymanrob]

27 minutes ago, Addicks Fan 1981 said:

Just looked at the NOAA 8-14 day chart anomoly and the mean trough does seem present still, but the mean trough to me doesn't look as vigorous as it did before or has done on previous runs, very similar to the ECM 00Z ensemble this morning actually.   

Climate Prediction Center - 8-14 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

Indeed, there is apparently some weakening, but maybe we are looking too hard. We need more runs to see if this develops further. 

[Cheshire Freeze]

45 minutes ago, mushymanrob said:

Indeed, there is apparently some weakening, but maybe we are looking too hard. We need more runs to see if this develops further. 

Also don't forget, during the warmer months a deeper trough is often BETTER if you want less copious rainfall. The low pressures tend to move through faster. It's possible we see pressure rise somewhat but we get stuck under slow moving, slack wave features that bring excessive rainfall...something that we have actually mostly avoided this summer.

Edited July 29, 2023 by CreweCold

[Addicks Fan 1981]

49 minutes ago, TheOgre said:

August 2021 was awfully dull and drab though, so even high pressure isn’t a guarantee for good weather.

It was an August that was an EQBO August, that in turn made the month quire changeable at times, what followed was a very nice September though and an opportunity to see some days in September to see the temps in the 30s.   

Hopefully the same thing can happen again this time if August is a bit dicey, because a very good September is essentially compensation.  By judging the CFS we could be in for a treat this September and possibly October as well.   

What we need short term for now is more WWB episodes as that will promote more settled weather, the east trades we've had periodically haven't done our weather much justice this month.   

Will be very interesting with what the positive IOD does from this day forward as well.   

[Rain All Night]

I was going to suggest that we see how the machine learning models compare with the ECM looking ahead to the Wednesday low, but in their latest runs they all seem to pretty much agree, so I've looked back at the last eight runs of each... the ECM has shown the low in some form on more runs than either of the machine learning models, one of which has only shown it for the first time on the latest run. But when the other has shown it, it's been in more or less the same place as now, which has not been the case for the ECM.

Edited July 29, 2023 by RainAllNight

[Rain All Night]

2 hours ago, Addicks Fan 1981 said:

stronger highs over Scandinavia need to develop

Is this any good?

⟹

[Addicks Fan 1981]

Just now, RainAllNight said:

Is this any good?

⟹

Getting there, not quite there yet, especially for the ensemble mean.    

[Snowy L]

I'm not going to get my hopes up or say things will improve but it does seem the low that hits us on Wednesday and then gives us the Northerly for the rest of the week is the last of the Atlantic barrage. After that a lot is up in the air and there's uncertainty about what then takes over. Maybe a chance of an improvement, maybe lows win again, but at least we have something of a raffle instead, just need some luck.

[Addicks Fan 1981]

1 minute ago, Snowy L said:

I'm not going to get my hopes up or say things will improve but it does seem the low that hits us on Wednesday and then gives us the Northerly for the rest of the week is the last of the Atlantic barrage. After that a lot is up in the air and there's uncertainty about what then takes over. Maybe a chance of an improvement, maybe lows win again, but at least we have something of a raffle instead, just need some luck.

Think @Daniel*latched onto with what probably is going to happen in his recent entry he put in here, he fully had my back on it completely.   

[Rain All Night]

I know this isn't much but it's a while since I remember seeing even the slightest positive MSLP anomalies over the last five days of the ensembles...

[MattStoke]

First time in ages 2 model runs have shown some promise for settled, warmer conditions.

[MattStoke]

And of course the ECM looks garbage.