I believe those are actually the values for when a Health Heatwave is triggered which will lead to certain steps being taken by emergency services. A Heatwave has a looser definition, but depending on the definition would not need temperatures as high as those.

I wonder why NW England has a higher threshold than Yorks & Humberside? If it's based on average max temps (as it would appear to be for everywhere else) I would expect Leeds for example to be a little warmer than Manchester. I'd understand the threasholds being the same but NW England being higher seems a little odd. Perhaps in the very hottest conditions that can ocurr with an easterly or even a south easterly, wiinds from the north sea mean that Yorks & Humberside are a little cooler than NW England.

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Already 22c in Doncaster. Many 21s and 20s. Should easily get 25/26 today. Hottest sustained spell for 7 years has begun.

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Whereas I'll be sat indoors the whole time as it becomes too hot to go out ......   Weather has been great for outdoor activities so far this summer (dry, often breezy) but that's all about to end.   Oh well, can't have it all!

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They don't have cold weather health warnings either  - the heat health advisories (issued by the Met Office to Dept of Health criteria) only cover England and Wales.

Of course, the threshold for an heat health advisory has no more bearing in whether it's a heatwave than the thresholds for a cold advisory do on whether it's a deep freeze

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Methinks there is a danger of this thread being overrun with a few overexcited heat rampers and a few more doom mongers about how its not going to be that warm or those who are going to die in the heat. Reminds me winter in an opposite sort of way!

Seriously though, the heat will bring a mix of issues, both good and bad. If we see a static HP cell parked over the UK for days then air quality will fall quite quickly, especially in London and that poses risks for asthmatics and others with breathing issues. I recall being in London in August 1990 on a "sunny" day at 34'C. Days of heatbuild had led to a notable petrochemical smog that made the sun very hazy. My half mile walk to the train station amongst the big buildings in the square mile was a sauna!

As for maxes, the orientation of windflow will favour certain places more than others.In 1990 it was Barbourne(Worcestershire) that recorded the hottest.

Places near me to the west or SW of London can do very well in a easterly drift.

I shall be off work next week so expect to be heading for the coast! 

 

That's true - the Office themselves have no god given right to define it I guess.

Also I wonder why London's is higher? You'd think a heat advisory threshold in London would be lower, due to the oppressive effect of concrete, tubes etc, and fewer opportunities/spaces to cool off. 

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What is it about years ending in "3" having good summers? 1983. 2003. 2013?

On heatwave definitions, I always thought the WMO defined a heatwave as five consecutive days with temperatures of 5c or more above average - On that definition the coming week does indeed look like a "heatwave" to me.

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Yes let hope this summer do the same.  1983 was constant warm to hot so we are possible looking at 1983 type here instead of 2003 as no models showing high 30's temps here and low 40's over France.

1993 crap though!

Yeah that was funny. All the hot summers in the 90's, yet the one you would think odds on to be hot, 1993, was the worst, with 1998, of the decade.

 

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That said, The record temeratures in 2003 were in August. There's definitely still time for all that

That's right - August is still the top dog summer month. The top four hottest days ever were all in August I believe.

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Met Office blog.

What is a Heatwave? (short answer is there is no official UK definition)

http://metofficenews.wordpress.com/2013/07/04/what-is-a-heat-wave/ 

I've asked myself this question before - one just needs to look at the historical data for both Leeds and Manchester to see that Leeds is usually warmer, both on average and during heatwaves, and the same applies for the rest of Yorkshire vs NW England - Yorks is almost always warmer. 

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I remember August 1990 when there was a week of 30 C-plus temperatures over the South and South East where apparently it peaked on the 3rd with 37.7 C (a whisker short of the 100 F mark) at Cheltingham.
   I was very fortunate in being off work on holiday leave on that week (it was booked a month in advance) - that was also when I was fresh into my first ever proper relationship, I was 23 at the time and I wasn't really of much use on that week due to how stifling hot it was. I rode my motorbike from my girlfriend's house to my house in just my shorts (as well as a helmet of course!) and it felt like being blasted at by a hairdryer as I rode along.
 
Anyway, in addition to my last post in this thread, I do have mixed feelings about it all. On the one hand I'd like it to be hot and sunny so that I could sit in the garden and get a bit of a tan on as I'm looking quite pale and close to getting rickets, but then the Addams Family next door will want to do the same thing and I get to hear all of them SHOUTING at the top of their voices as well as the smell of cigarette smoke and dope wafting my way.
  Like I said before, it looks like bike rides out into the countryside or beach - with camera on tow of course - will be a regular thing for me. But if it does tend to get cool and misty then those bike rides would become less appealing, but on the other hand it'll make it quiter and peaceful around here as no one would want to hang around outside for too long.

The proof will be in the pudding over the next few days regarding the weather for this location.

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Heatwaves are ok, as long as there is a real good thunder breakdown at the end of it

Let's get some cracking storms going, for pete's sake

Must say, my confidence is low on that, at the moment

Being a hayfever sufferer, i'm not looking forward to the very high pollen counts

Desktop fan will be purchased tomorrow... stay cool

Bring on the heat

Nitpick - 37.1C. The hottest 5 days on record are

10 Aug 2003: 38.5C (38.1C at Kew if you discount the Brogdale reading)

3 Aug 1990: 37.1C

9 Aug 1911: 36.7C

2 Aug 1990: 36.6C (potentially a dodgy reading)

19 July 2006: 36.5C

 

Just illustrates how much hotter 2003 was. None of these measly few tenths, but a full degree (or more) hotter.

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Indeed, had a feeling 37.7 C wasn't the correct figure as I noticed it down on my personal records (was too lazy to google it up), still, the 37.1 C achieved was memorable as that was the first time I've "seen with my own eyes" that kind of heat as I was into meteorology for about ten years at the time (I was 8 in 1976 and I remember the 33 C in July '83 as that was my last year at school).

But getting back to the here-and-now. I'm glad I'm no longer in the tomato greenhouse trade, I would be greeting this upcoming warm spell in utter contempt!

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You can enjoy this warm/hot spell this time Ian. I remember the pics you put on here of your tomatoes after the hot July of 2006.

Amazing that is now 7 years ago.

 

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So, do people think this weather we're about to get marks one of those "pattern changes" that occasionally happen, like May 2007, Nov/Dec 1988 etc. Or is it just a spell of nice weather before the topsy turvy jet re-establishes for the next 5 years?

It strikes me that the North Atlantic pattern we are seeing, with depressions spilling continuously over the Southern end of Greenland, is something that has happened rarely if at all for many years.

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The heat on that fateful day was so intense, it destroyed half the crop under glass (there was a bad outbreak of red spider mites as well so it was a double whammy effect). However, because every tomato greenhouses around the county suffered the same fate, it caused fruit prices to go shooting right up as it became a valuable commodity. As a result we actually made a profit on that year!

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I think it's a continuation of the pattern we've been seeing for the past few years due to a weak, meandering jet stream.  Only this time we're in the right position to tap into some heat rather than cold and wet!  

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You could be right - after all the pattern of the last six years has resulted in several heatwaves in Europe, just too far east to affect us.

 

BTW re August 1990 I do remember that heatwave - probably the first one I can place. I was on a Scout camp in Devon. I remember on the hottest day we all went swimming in the local river for most of the day to cool off. 

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30C for Yorkshire and north Midlands at the end of the 'high-res' GFS run.

http://cdn.nwstatic.co.uk/gfsimages/gfs.20130704/12/192/ukmaxtemp.png

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