I like the Arpege charts- have they been improved to show clearer temperatures away from the zones of steepest thermal contrast (you know- where the therms are so close together it's hard to pick the right number for your location)? Really clear for the next few days.

 

 

 

 

---

I'd like to bank P08 of the 12z GEM ensemble. Yes, GEM.

Obscure? Yes, but it's quite simply the hottest model run I have ever seen. Go and take a look.

(P20 isn't bad either)

---

Sadly the trend has gone into reverse across most major models again. Just once again proves the volatility in trying to predict confidently more than a few days ahead. Next week is very much up in the air at the moment with a brief burst of warmth followed by a spell of something much more changeable again. Pretty much a repeating pattern this summer with it looking worse the further north you go.

---

The models haven't changed much from yesterday unless you cherry pick an op run to make your point.

PS: A senior admin wasn't banned on TWO but one or two members may have their accounts deleted today.

---

The ECM 0z is considerably different to the UKMO and GFS and offers a lot dry weather after the midweek blip..the models are and remain in a fairly volatile state and what appears certain is a brief significant warm up in the south. It's been a very interesting summer thus far and as Brian has said a few times there appears to be a repeating pattern of warm bursts followed by slightly more changeable. I think this is most likely to continue with the best of it remaining in the south. ECM certainly strongly backing another big push from the Azores next week. More runs needed as ever

---

Over the reliable timeframe we can look forward to some decent summer weather - it won't be roasting but that certainly doesn't bother me. My BBQ over the weekend looks a safe bet. Beyond that is anyone's guess.........

---

At the risk of joining the misery mongers though, the GEFS mean is below average from next Friday until the end of the run. So something needs to give. Very different from the slow stable rise in airmass temps being shown only a few days ago.

Critical moment for the summer, as the schools start to break up just as next week's plume ends.

---

ECM is better though and shows more influence of the AH. SW areas best.

---

Big divergence between ECM & GFS at 144H this morning which has the trough really digging in and forcing the high away with the jet strengthening and heading south. Wonderful ECM charts though  

Let's see if the very positive Meto update continues today,

Could be some good model watching coming up over the next few days.

 

If the GFS was being upgraded a week earlier this would have been the 00z op run.

---

At the risk of joining the misery mongers though, the GEFS mean is below average from next Friday until the end of the run. So something needs to give. Very different from the slow stable rise in airmass temps being shown only a few days ago.

Critical moment for the summer, as the schools start to break up just as next week's plume ends.

Early days Tim. Will it! won't it model drama for a little while yet. I'll take 72h at a time for sanity...

---

St Swithun's Day is looking rather wet for many parts tomorrow

If the GFS was being upgraded a week earlier this would have been the 00z op run.

struggling to build in - But gradually getting there. That low pressure over southern Norway is a real pain. There is a high pressure behind it as well.

---

St Swithun's Day is looking rather wet for many parts tomorrow

Yep, if you went by the St. Swithin's Day legend rather than the models, you would say that it's not looking good for the rest of the summer in this part of the world with rain forecast for here during tomorrow. On the other hand, the outlook would be really good for the rest of the summer in those areas which are forecast to stay dry tomorrow if you went by that.

---

Met/o and GFS 00z generally unsettled, where's the ECM turns briefly unsettled and cooler but the AH ridge builds in, in fi along with the warmth.

I would say at the moment the ECM is more realistic as its the pattern we're had for most of this summer so far.

---

Have to be honest and don't look at the GFS, it has shown over the last year how bad it is.

---

The cyclonic output in the 06z GFS rather worryingly is backed up by 13 ensemble members which all have a low over the UK at T196. Looks like cold air leaking south of Greenland is really going to scupper the heat staying after the middle of next week.

I'm off to Lake Garda on 22nd July, I may have picked a good week to get away from the British weather!

---

The cyclonic output in the 06z GFS rather worryingly is backed up by 13 ensemble members which all have a low over the UK at T196. Looks like cold air leaking south of Greenland is really going to scupper the heat staying after the middle of next week.

I'm off to Lake Garda on 22nd July, I may have picked a good week to get away from the British weather!

Couple that with the GEM and we now have considerable uncertainty.

I'm favouring a more blended solution now whereby an area of low pressure moves NE'wards to the west of Scotland with a gentle rise in pressure from the Azores thereafter. Southern UK largely unscathed with temps remaining in the warm category throughout. 

Things have gone downhill though in the last 36 hours of model watching. From looking how hot we could have got we are now faced with looking how close and how deep the offending low pressure system will get.

---

Well, we sure have been treated poorly by most of the operational models these past 48 hours now haven't we?

Talk about small-scale details throwing spanners into the broader-scale pattern (Azores High extending NE to Scandinavia)! Essentially we have GFS in particular looking to wedge a cut-off low in between Azores and Scandinavian highs such that the broad picture is almost as it would have been anyway, but with a small region being markedly different... a region containing the UK, because how could it not  be that in the mid-range GFS output? 

 

So I find myself looking for what we need to happen in the shorter-term in order to score something akin to the ECM 00z run instead.

  

Here are the 'Big Three' arranged side-by-side.

What we see is that GFS and UKMO have the small low west of the UK in an elongated shape such that it more or less resembles an extension of the deeper trough near Iceland, but ECM has this low as a distinctly separate feature - pretty much cut-off from the main Atlantic jet stream.

This is crucial because the cut-off means interaction between the low and the deeper trough to the north doesn't occur over the following 24 hours, which is when the latter is well-positioned to not only exploit the resulting enhanced temperature gradient (it has cool polar maritime air on its side, while the small low has some tropical continental; much warmer) and intensify, but also guide that thermal gradient such that it pumps up a section of the jet stream running NW-SE and passing a little way SW of the UK. This means that the strengthened low is driven SE and over the UK. At this point, upstream developments cause the main Atlantic jet stream to resume a SW-NE orientation and, like a meander in a river being severed, this leaves the aforementioned low wandering aimlessly around the UK in the case of GFS. This did seem particularly bad though, with GEM showing a plausible alternative in which the low soon drifts south into Europe while blocking becomes strong between the mid-Atlantic and Scandinavia.

With the interaction delayed to the following day as per the ECM 00z, the low is not as well-placed to deepen, and the fact that it's further northeast means that even if it does move SE, it misses the UK, leaving the door open for the Azores High to build in. The realignment of the Atlantic jet as mentioned above then works in our favour rather than against.

 

So the main point to take away from all that is - we need that little low to be as far south and independent from the Atlantic trough as possible in the 3-4 day range. All eyes on the 12z in hope of seeing such amendments from GFS, GEM and UKMO so that we may escape the extraordinary misfortune that their 00z runs suggested! 

---

Dry and fair with sunny breaks and partial cloud and a very comfortable 22.7 C, just a bit of a north west breeze keeping humidity levels at 40%.

I really couldn't have picked a better day to extend my back yard. I've adopted a long since abandoned and closed off pathway which has never been touched by anyone - including the council - for two decades so I might as well have it, especially as I paid to have a sycamore tree cut down from there. It's only a metre wide but might as well make use of that wasted space to put a new weather station there.

---