Hottest day of the year today 29.4c St James's Park.

This week doesn't look anything extraordinary but Ireland could get its warmest day also 30c in Manchester possible which is unusual.  Aberdeen might even get to 18c 

Snap

just hit 29.5c here too 😎

29.6C here, on my weather station.

Actually not joking lol

30.1C here according to my VP 2.

There's a weather station at the University of Leeds that is currently 29.8C. 

A high of 30.5C here today.

Happy with the more muted 26.8C here- as the sea breeze has a little late influence here. Hottest of the year so far here.

I know that car thermometers are notoriously unreliable but mine generally does a decent job. I came out of work and was astonished how hot it was. The car said 28C when it settled down, and I thought it couldn't be so as the maximum progged for today was 23C. However a quick glance at the MetO forecast indeed does show 28C!

What went wrong (or right, depending on your view!)?

MetO automated always underestimate temperatures IMO. When I looked on Thursday last week at the weekend and beyond it showed 19c for Saturday, 21c Sunday, 24c Monday, 22c Tuesday, 21c Wednesday. We actually had 21c Saturday, 25c Sunday, 28c today. It now shows 25c for tomorrow. A little slow to catch up, and I daresay we'll beat 25c tomorrow as well.

Amazing. :) 

I notice the high at Rostherne and Manchester Airport was 28C.

How confident are you with your reading being accurate? You will have more of a UHI effect compared to the airport so I can certainly believe it. 

This was off the personal forecasts, for example Simon King this morning, but also on the TV (probably not MetO of course any more, but the point is the same). The peak here was supposed to be about 27C on Thursday.

I think we hit 28/29c in Stoke today. Dare I say unusual to get those high temperatures without the humidity.

It was also quite cool first thing this morning so big diurnal range.

I love humid weather but cannot beat the Med feel with crystal clear skies and not the hazy look of a blowtorch setup, rare for this part.

Well for what it's worth the Met forecast for Leeds now shows 27C tomorrow - though I wouldn't be surprised to exceed even that.

And the Met I believe originally showed a max of 25C but then upped it to 28C today when they realised they underestimated the temps. They do that a lot. When it was 25C by 11am it was pretty obvious it was going to be much warmer.

Official we hit the big 30 today 30.1c at Hampton SW London.

ARPEGE 12z run did model 30C this afternoon in west London

Tomorrow it is going for 32C somewhere around Stoke-on-Trent and also just south of Bath and Bristol

http://modeles7.meteociel.fr/modeles/arpege/runs/2018062512/arpegeuk-41-28-0.png?25-18

Whilst its no heatwave IMBY, its a brilliant spell of sparkling summer weather. What irks me is the inaccuracy of the Met Office forecasts for maximum temperatures.  They widely went for 18c max here, whereas it was 22c IMBY close to the coast, with 25c at the other end of town, up the valley. So, forecast maxima were between 4 and 7 degrees out.  That is plain embarrassing.  If they are making forecasts for Langdon Bay (400 feet up on a cliff close to the South Foreland), then the forecast maxima may be more accurate but are very misleading as to the actual maxima in Dover.

The Met office max temp forecasts are so bad that I add on 4c to the raw forecast data and that gives me a more accurate picture.  

33C on Thursday.

https://www.theweatheroutlook.com/twodata/arpege.aspx?run=na&charthour=76&chartname=uk2mtmp&chartregion=uk&charttag=2m%20temp%20C

28.8*C here, reached mid-afternoon before the sea breeze set in at around 4 pm.
This happening on a day that the GFS 06z of 21st forecast to max out at 24*C, and the 00z ECM of 20th forecast to max out at 23*C.

Even the 00z and 06z runs of today didn't go above 26*C here.

ARPEGE, on the other hand, predicted 28-29*C from the moment today came into range. I think one run had a 30 but I can forgive it for that .

It sure does set the mind wondering just how high the temps could go during each of the next 5-7 days. 

The same magnitude of error by the global models would mean 27-28*C here tomorrow (GFS 1*C below ECM), 28*C Wednesday, 29*C Thursday, 28*C Friday and 28*C Saturday.

Not a bad run at all. I think Thursday could well reach 30*C as the sea breeze should be held at bay and I tend to see the largest modelling errors when winds come from inland all day long. ARPEGE agrees with my thinking.

I wonder just what it is that impedes the global models so much. At a guess, they fail to modify the boundary layer airmass sufficiently - a theory I believe is supported by the fact that in dry air I often see the nights being overestimated as well; the diurnal range exceeds the predictions in both directions.