model discussion Model output discussion 11th July onwards

[mb018538]

UKMO 12z 144-168 going quite aggressive in developing low pressure middle of next week. A couple of days ago it looked like a fairly weak flow might prevail, now it may just be wet and pretty windy instead!

Edited July 22, 2021 by mb018538

[Frosty.]

No comments on the 12z? ...hmmmmm, anyway...Now this is more like it from the Ukmo 12h T+144 hours. ...cool and cyclonic...I wonder if reverse psychology will work this time?.. ...probably not, we’re doomed to a more unsettled and cooler outlook but if there’s some claps of thunder?, it will be worth it!.. ⛈  

 

 

 

Edited July 22, 2021 by Jon Snow

[damianslaw]

Good post from Tamara looking at longer term prospects. One new factor that emerges in August is tropical storm activity. Always a tricky one to forecast and can make for sudden developments and major uncertainty. Statistically settled sustained conditions in latter part of summer becomes harder to achieve.. we are seeing a very see-saw summer it seems, but unusually the north and west is doing better than the south and east, with trough action settling in a more southerly position than usual inbetween the strong ridging often establishing to the NW.. indicative of the la Nina influence.. with suppressed azores high. The default pattern is for a more northerly positioned trough with azores ridge into the south, but this isn't the case this summer.

[mushymanrob]

1 hour ago, JayAlmeida said:

 

Makes me laugh when people take anomaly charts in the 8+ day range as gospel and then proceed to get highly defensive when you point out that anything beyond 7 days is speculatory at best.

With a 70-75% accuracy rate (according to John who did the research) they are far more than "speculatory", but no one takes them as "gospel" , they are the "most likely" scenario.
So please stop the snide inaccurate comments thank you.

[Methuselah]

1 hour ago, JayAlmeida said:

As close to gospel as can be gotten then is that better? 

And any disagreement with said assertion shall be met with contempt.

Something like that...

Nyet! No 'contempt' from here, merely disagreement!

Edited July 22, 2021 by Ed Stone

[Frosty.]

Again there are hints from the GEFS 12z that early (ish) August might see the trough domination weaken and start lifting out with perhaps the Azores high / ridge starting to wax which would be very good news for summer fans and would tie in with the longer term signal from the pros for a marked improvement towards mid august?..but it could be far quicker than that if any of these perturbations verify...but i must stress there is plenty of absolute filth more suited to October within the ensembles during the early august period but as you guys know, I look for the positives in any situation! cherries included of course!  

 

Edited July 22, 2021 by Jon Snow

[Captain Shortwave]

Quite an extreme blocking set up appearing with strong ridges east and west of the U.K. initially rain looks to be restricted towards the south in with showers or long spells of rain, however they look like becoming more widespread into next week as cooler air arrives from the northwest.

   
 

In any sunny spells it will probably still be fairly warm, however the potential for a lot of rain exists for many, and the introduction of cooler air will not prevent the formation of slowing moving showers either as cool air aloft aids the traditional sunshine and showers scenario.

[kold weather]

4 hours ago, Tamara said:

The next window of opportunity most likely to come after the first 10 days of August. Eyes after that time on a possible  (stronger) intra-seasonal response within the tropics to shale-up momentum once again through the middle and second half of the month and which might come on the heels of residual tropical activity in the Atlantic bred from an African wave upcoming as the MJO traverses the Western Hemisphere (and when lack of wind shear is conducive for storm and hurricane development). This could shake-up the Atlantic profile somewhat as often happens in the latter part of the summer. This, while highly credible, is of course somewhat speculative so far out in time - but something to look out for.

Just to further that point long range models are kinda suggesting 3rd week of August looks a likely time for MDR waves to start having a more positive setting to develop into Tropical cyclones. (both Climo and the MJO are suggestive of that) The pattern the models are suggesting mind you means that if they take a little while to form they will end up getting trapped under a decent upper high over NE Canada which typically shunts any long tracked MDR storms into the Caribbean/Bahamas region.

Assuming that we don't get any early wildcard systems (and its far from impossible that some homebrew stuff near the states develops to throw a wrench in the pattern) we may well see the Atlantic kick start in quite a big way for the final 3rd of August. Should the long range models be broadly correct (and there is decent agreement regarding that upper high location) it maybe a further 7-14 days on from that before any tropical factors in the Atlantic really stand a big chance to shift the pattern in this neck of the woods. So final part of August, maybe even early September.

Of course it'd be just out luck that the pattern shifts favourably before that point only for tropical forcing from TCs to shift the pattern back again!

As for closer in, despite it clearly cooling down I don't think we are quite at disaster territory yet, it looks like at least the LPs will be on the move and not just sit around like the SE (and of course Germany!) have seen. Its the type of pattern that will probably have some bad days where fronts cross, but also days with sunshine and showers, which are still infinitely better than what us in the Se had to endure during the 2nd half of June and early July.

Edited July 22, 2021 by kold weather

[bluearmy]

Looking for some summery hope from the weeklies ?   Looks like they’re late ! 

[Frosty.]

If it was winter, on the face of it, tonight’s ECM 12z ensemble mean day 10 would be very encouraging for coldies with a mid Atlantic ridge building north and a Scandi trough but entering the final third of the meteorological summer it’s potentially very disappointing..BUT..it only takes us to August 1st so there’s plenty of time for summery weather to return next month..and for what it’s worth... I believe it will!!
 

[stodge]

Evening all

Another very poor set of charts for the beginning of August.

JMA is spectacularly awful with a mid-Atlantic ridge leaving the LP right over the British isles (if only it were winter etc).

Most of the others reference some form of northern blocking or Greenland heights - the one hope might be a west-based negative NAO of sorts holding the LP further west and dragging very warm and humid TM air up from the south west but there seems little prospect of that.

With the jet pushed south, the saving grace is the LP are shallow and slack so we're not talking deluges or the kind of August storms we have seen in the past (Fastnet Race disaster of 1979).

Nonetheless, hard to see anything settled to start August but it's a long month (same length as July) so plenty of time for the background signals to be more helpful and especially if we see some hurricane activity which can inject some energy into the atmosphere.

[Howie]

I thought we were gonna have at least some high pressure after the heatwave, can't believe it's deteriorating this quickly. Hopefully going into August it will improve

[JayAlmeida]

4 hours ago, Ed Stone said:

Nyet! No 'contempt' from here, merely disagreement!

The contempt part wasn't aimed at you. ✌

I was merely re-phrasing my original post so it sounded closer to 70/75% of gospel.

Edited July 22, 2021 by JayAlmeida

[Guest]

1 hour ago, Jon Snow said:

If it was winter, on the face of it, tonight’s ECM 12z ensemble mean day 10 would be very encouraging for coldies with a mid Atlantic ridge building north and a Scandi trough but entering the final third of the meteorological summer it’s potentially very disappointing..BUT..it only takes us to August 1st so there’s plenty of time for summery weather to return next month..and for what it’s worth... I believe it will!!
 

This was the GFS chart from a week ago, basically the one I said would come off because I’m going away (well soon to be was going way) Pretty good parity with that ECM mean.

 

[Liam Burge]

I feel like my storm chances here just got better, especially considering the MetOffice people specifically mentions my area as a hot spot for "pretty vicious thunderstorms".  I believe my best bet at seeing thunderstorms is around 4pm though, as many forecasts agree on this time.

Edited July 23, 2021 by Liam Burge

[mb018538]

Looking very unsettled into the middle of next week with some strong winds and heavy rain in places. Temperatures really struggling - low to mid teens in the W/NW, perhaps mid to high teens in the east.

[Eagle Eye]

@Liam BurgeI think you were right about Icon, it has finally joined in the act, upping to 30-35% chance for you today, next run if it stays the same, 50%.

[northwestsnow]

So jealous of those with storm chances , we just don't seem to see hardly any locally in recent years...something magical about temps in the high 20s and a storm,jealous or not I will look for some pics !

As anticipated it does take a good 3 or 4 days for the warmth to drain away so I'm thinking low to mid 20s until Tues, with showers  of course.

Probably goes downhill after that,but for how long,who knows...

[mb018538]

Lots of high latitude blocking on offer from day 8-15 on the ECM clusters. Looks like my holiday to Dorset from the 31st July is going to be mainly rubbish 

[mushymanrob]

Evidence of the NOAA accuracy?

On the left is the 8-14 day mean issued on July 12th... that covers the period July 20th - 26th, of which today, the 23rd, is mid point therefore should be the closest match.
On the right is the current latest ECM 500mb chart for today.

Azores high just west of the Azores.... check
Low over baffin ..................................... close
Shallow trough to our southwest ........check
High pressure to our near EastNortheast ..check
Strong flow out of USA / Canada tracking over North Scandinavia .... very close.

With repeated chart accuracy in this timeframe, it underlines my POV and why im so keen on them.
 

[Guest]

43 minutes ago, mb018538 said:

Lots of high latitude blocking on offer from day 8-15 on the ECM clusters. Looks like my holiday to Dorset from the 31st July is going to be mainly rubbish 

Just giving it a couple more days before I pull the plug on Torquay. Don’t mind low 20s and a couple of Showers but not spending a fortune to spend 3days wrapped up in jumpers hiding from the rain…

[Northwest NI]

7 minutes ago, Alderc said:

Just giving it a couple more days before I pull the plug on Torquay. Don’t mind low 20s and a couple of Showers but not spending a fortune to spend 3days wrapped up in jumpers hiding from the rain…

Yes still perfect weather up here for another few days but it looks like my Netflix account, which has been dormant since the end of May, will be getting visited quite a bit soon.

[MATTWOLVES 3]

Another cracking day folks...Big area of rain and thundery activity now coming out of NW France and approaching the SW...im sure @Eagle Eye @Allseasons-si @Zak M and the other storm chasers I've missed out(apologies guys im struggling to tag people here) are feeling like kids in a candy shop! Bring me some bolt lightening guys and im hoping you get chance to put those cameras to good use.

Interesting to look at my local weather and radar app and there 14 day trend today!! Sunshine and showers next week,with perhaps more organised showers and rain bands next Weekend! Beyond that it settles things down again! Obviously this is a long way out and we all know the pitfalls of forecasts beyond 10 days....but perhaps the signs are growing towards pressure finally building again from the SW. The 6z mean does hint at an improvement beyond next week,with perhaps the unsettled conditions being pushed further North with time.

Until then enjoy the sun and Heat..and those potential storms from this evening  onwards.

Edited July 23, 2021 by MATTWOLVES

[mushymanrob]

28 minutes ago, MATTWOLVES said:

Another cracking day folks...Big area of rain and thundery activity now coming out of NW France and approaching the SW...im sure @Eagle Eye @Allseasons-si @Zak M and the other storm chasers I've missed out(apologies guys im struggling to tag people here) are feeling like kids in a candy shop! Bring me some bolt lightening guys and im hoping you get chance to put those cameras to good use.

Interesting to look at my local weather and radar app and there 14 day trend today!! Sunshine and showers next week,with perhaps more organised showers and rain bands next Weekend! Beyond that it settles things down again! Obviously this is a long way out and we all know the pitfalls of forecasts beyond 10 days....but perhaps the signs are growing towards pressure finally building again from the SW. The 6z mean does hint at an improvement beyond next week,with perhaps the unsettled conditions being pushed further North with time.

Until then enjoy the sun and Heat..and those potential storms from this evening  onwards.

what "sun and heat"?
 

[MATTWOLVES 3]

8 minutes ago, mushymanrob said:

what "sun and heat"?
 

26c and Sunny here...hazy but glorious... 

Yes that imagery is picking up on the High level cloud cover...the standard imagery is showing a sunny day for many,but that wouldn't be showing the very high level cloud cover...lovely here in Costa Del sedgley though

Edited July 23, 2021 by MATTWOLVES