kold weather

danm Big overperformance in the London area today vs the models, some really poor forecasts indeed. ECM going for 21-22c, ICON on its 00z went for 22c for example. GFS wasn't much better. Only ARPEGE and UKV seem to have done a decent job. Pershore though really is the standout there!

Man With Beard This is what I've been using: Wetterzentrale.de - Diagrams WWW.WETTERZENTRALE.DE Forecasted 2m Temp. from AIFS, 12Z Now admittedly we can't see what the pressure is doing, nor the individual ensemble members on this so it may just be a case that alot of them are going for the same broad pattern just maybe a little less aggressively than the OP. I personally think there is a decent chance of a breakdown of sorts, in that the air is shifted away and we do get some frontal/convective rain in, but I also got a strong feeling the Azores high will ridge back in again and the models will pull back on elevating the upper high as far north as they are. I suspect we will see a proper breakdown like the AIFS is showing but I think its probably just overly progressive in it and we've got one more major ridging event to come through after this weekends event. From what I've seen of the AIFS, its very good at the big picture stuff, but this is when of those situations where a relatively modest shift either east or west of the main upper low around 120-168hrs is going to lead to very vastly different evolutions,

Man With Beard I think the AIFS ensembles gives a good clue to that, the operational run is consistently and has been consistently one of the coolest members for the whole country over the past 4 runs or so, and as I said in the previous post post breakdown I think gets technically above the average ensemble mean temperature wise for maybe 12hrs out of a 180hr period...and even then its only *just*, and often its in the bottom 10%. That of course doesn't mean its not got the right idea with its operational run, on alot of the hotter 'normal' OP runs from the other models there is a really fine line between the hot runs and the LP just edging a little too far east. For now though based on all evidence I'd say the AIFS solution is probably on the cooler end of the spectrum and the hotter ECM/GFS runs probably the other end of the range.

I've seen alot of chatter about the 12z AIFS not being amazing in later ranges, worth noting that at almost no point in its entire run from the 'breakdown' onwards did it break above the average of the ensemble line, it was nearly always right towards the bottom of the ensemble pack. Whenever you see something like that it makes it far more likely that its overdoing something within the signal, especially when other models resemble the mean of the ensembles or above far closer.

clark3r I doubt there'd be any significant breakdown before the end of JUly should that happen. Again these sorts of runs do feel a little on the extreme end, albeit a plausible solution. We do seem to have a rough idea going forward now, heatwave from Wed/Thurs - Mon, then a cool down relative to where we were but probably still above average for the south at least. Another ridge likely to attempt to move in, some uncertainties how far north it ends up but it feels likely that tje south at least remains warm and fairly dry, less certain the further north and west you go.

Alderc 2.0 Yeah in the south we remain above average throughout, and in some places still cling onto a technical heatwave even. Some convective fun and games on the 19th on this run but thats going to be nowhere near enough to counteract what is basically a 2 week period of above or well above normal weather, I remember saying that I feel a reload pattern as we saw in 06 and 18 was still the most likely solution, the models are still not totally confident but I think the pattern will happen, its just whether the LP gets far enough east to have any influence or not.

Echo what others have said, very nice day today and in a more standard summer this would be regarded as a perfectly acceptable summers day. The next 10 days at the moment are looking pretty outstanding locally. Even GEM which is probably the coolest overall run is still giving maxes of 24-26c the following week which is still very very useable indeed. Also with the drier air coming in it should mean that outside of maybe some cities I don't think temperatures will hold up too high overnight so hopefully it will aid in stopping houses getting too extreme in terms of temperatures,

What's the hottest first half of summer CET wise? Given we are probably about to go on another 20c cet day run this summer must be up there with the warmest?

WeatherFanatic123 Broadly similar breakdown, though a subtle but meaningful difference this time as the upper low departs to the east rather than just sit over the UK like the 00z. I suspect this run will be much closer to the mean of the AIFS ensembles than the 00z operational run was. Temperatures somewhere close to average, and probably thats 1-2c too low as per normal. In high summer, average temperature, particularly further south, will feel very nice still (and actually might be quite wanted after 5-6 days of 30c+)

WeatherFanatic123 yeah you'd have to imagine its a very probable evolution where eventually the atlantic energy does get far enough west. Looks very feasiable to me. That being said, down in the SE its still not that bad, a little wetter for sure, but still holding maxes comfortably above 25c. I admit for your location the 06z GFS is far rougher...

WeatherFanatic123 on the upshot the AIFS is indeed quite cool on its own ensemble, suggests the operational run was on the lower end of what is priobably the likely scenario. For example in London the operational was ranked the 45th coolest out of 49, so only 4 runs were below it and most of those only marginally so. So in much the same way as I wouldn't be putting too much stock on GFS run post Sunday/Monday given how hot it is, I also wouldn't be putting too much stock in the operational run of the AIFS from the 00z suite either.

Only slight good news on the rain front is the models have upper rainfall totals tomorrow, a reasonably broad 5-10mm now forecasted and some areas may well get more. Of course whilst every little helps, I'm not sure how useful thundery rain will be given how dry the soil is, but also with at least a week of dry and temperatures at least above 26-28c very widely, and in some parts much higher again, it's not really going to change the situation at all...

Fourty Point Three Degrees to be fair it DID get to nearly 36c, it wasnt that drastic of an overcook... Locally that 18z is pretty awesome, perhaps a lick cooler at times than further west/NW of my location but 10 days above 28c and many if those north of 30c is by any standards outstanding.

Just looking at how the models handle Chantal, the quicker the Tropical storm ejects into the jet the more progressive the pattern will be. The extra energy basically seems to force the pattern just far enough east and the blocking ends up being further NE as a consequence.

A little drizzle at times here but more or less meaningless. Should we go another 10-14 days without meaningful rain and warm/hot conditions the local lake I visit will be under severe stress.