Possible 30c

[kold weather]

Really they should either make it an offical station or a compeltely unoffical station IMO. So we obviously have hit 30C but its not offical offical if that makes sense?!

So its an unoffical 30C but a 30C nonetheless, god its confusing!

If I'm honest thats just stupid, if its not going to count then take the LWC temp off the Met office site because its not offical!

Edited August 8, 2007 by kold weather

[Terminal Moraine]

Re WIB's White Christmas:

This is true, but temperature readings are subjected to more stringent sitation criteria than occurrences of sleet or snow falling. The same goes for rainfall and wind speeds.

The fact is, a station could quite easily be taken as 'official' if it was in a city centre, provided that it met the Met Office criteria for Stevenson screen height, building proximity etc. By contrast, if a station was in a remote area but the thermometer was situated unscreened in a field, it wouldn't be 'official'.

The reason why they do this is so that a line is drawn somewhere. I'd have an issue with it if the line kept moving, but there's no way that would happen here- the MetO want to keep the line in a consistent position so as to make current records consistent with historical records. Why does a line need to be drawn? Put simply, because otherwise you could put a thermometer, unscreened, resting on a large expanse of concrete and say "officially it reached 46C today!"

A succinct summing up there, TWS.

It is important that a line is drawn and strict criteria adhered to with regard to official stations if readings from across the country are to be comparable.

On the other hand the number of station inspectors are so few that even the official stations do not always meet the required standard. I've visited many official and unofficial sites over the years and a few of the official ones have been in such a lamentable state of upkeep that the readings obtained were no more, and in all probability less, accurate than many good amateur stations which would not meet Met' Office criteria.

With regard to the issue of whether or not 30c was reached, well yes it was but if it was on the roof of the London Weather Centre it will be no more valid in representing the surrounding area than if the same site had recorded an absolute min' of +1.0c during a winter month when every other station nearer to ground level had recorded an air frost.

I'm sure that when all the readings are in at the end of the month there will be someone who recorded 32 or 33c in their sheltered back garden but the validity of such readings apply only to sheltered back gardens; the London Weather centre readings equally apply only to rooftop sites within that area of London.

T.M

[saint]

thanks everybody who answerd my question-thanks

[West is Best]

Just one further thing to this: I hadn't fully appreciated the point about waiting until the end of the month. Some stations don't report until then. St James' Park is, I understand, often extremely close if not identical to the LWC despite it's non-urban setting (well, you know what I mean!). Some discussion on TWO about the problems with SJP because it's actually useful to have a station which is located in the reality of the London UIE.

Complicated stuff. If we didn't set an arbitrary bar for which temperatures have to jump over then the arguments would become more objective. There's something to be said for that as it's easy to put one's own slant on something. The fact that Conigsby was within 0.6C of the LWC is in some ways more interesting than waiting on the final confirmation or not of 30C somewhere - it showed that 30C, give or take, was spread far north of London.

[Nick F]

Complicated stuff. If we didn't set an arbitrary bar for which temperatures have to jump over then the arguments would become more objective. There's something to be said for that as it's easy to put one's own slant on something. The fact that Conigsby was within 0.6C of the LWC is in some ways more interesting than waiting on the final confirmation or not of 30C somewhere - it showed that 30C, give or take, was spread far north of London.

Both Coningsby and Holbeach reached 29.7C on Sunday early evening (18z maxes at the same time as the 30.3C at LWC) according to official sources, so could well be that somewhere in South Lincolnshire or Cambridgeshire could have reached 30C, just not by official measurement.

The 30.3C at LWC on Sunday still serves as a useful measurement in terms of urban warmth, even if it does not fulfill official measurement purposes.

[Scorcher]

No, sorry, this is wrong. As far as I'm concerned, it is the siting that is the problem. The Met Office have a station in Manchester Hulme Library in the centre of Manchester. As far as I'm aware, it is a standard site - so fine, I would accept readings from that site.

It's interesting you should mention that station- it recorded 30C in the middle of July 2005 (can't remember the exact date) which made it the warmest spot in the country but it was given little or no mention on these forums. The BBC mentioned it on their website but the impression I got from the reaction on the forums was that it was a not a standard site. During the first heatwave last year some people who live in the Manchester area suggested it was the first time 30C had been reached in Manchester since 2003, but if this site is a standard site then surely the reading from July 2005 is official.

[West is Best]

It's interesting you should mention that station- it recorded 30C in the middle of July 2005 (can't remember the exact date) which made it the warmest spot in the country but it was given little or no mention on these forums. The BBC mentioned it on their website but the impression I got from the reaction on the forums was that it was a not a standard site. During the first heatwave last year some people who live in the Manchester area suggested it was the first time 30C had been reached in Manchester since 2003, but if this site is a standard site then surely the reading from July 2005 is official.

As I was having a siesta today (no don't laugh, I have to get up very early to teach french kids!) I was thinking how different the centre of Manchester is from, say, the Square Mile or Oxford Circus in London. Anyway, this whole issue is getting more bizarre. Philip Eden now has the 30.3C on his site in italics. OP suggested this is because it is unofficial, but he also has a Gravesend reading in italics. Is it that, or is it that it's currently unconfirmed? (I.e. we await the end of the month for confirmation?). Just to add to my confusion, he's listed it as Clerkenwell. I didn't realise the LWC is in Clerkenwell? Anyone know?

[Weather-history]

. OP suggested this is because it is unofficial, but he also has a Gravesend reading in italics.

Philip Eden has public said on the Weatheroutlook forum that the 30.3C at LWC is unofficial.

Gravesend is a non standard exposure site.

Edited August 9, 2007 by Mr_Data

[West is Best]

Philip Eden has public said on the Weatheroutlook forum that the 30.3C at LWC is unofficial.

Gravesend is a non standard exposure site.

Blimey Kevin ... how many more of these are there? Is there a list of official and non-official ones?

It does seem to me a bit bizarre that there is no other central London station (except St James' Park which I think we still await). I still think therefore that 30C was reached in London, but that this is affected by the UIE.

[kold weather]

That sounds reasonable West though I'm pretty sure somewhere probably got upto 30C given there was a max of 29.7C I believe at an offical site. so to conclude we have'nt offically hit 30C this summer, at least according to the data we have right now?

(ps, I'm surprised the Gravesend station is nonstandard as well I have to admit, esp given I've seen it used in monthly reports before.)

[Nick H]

Richard I can confirm LWC is in Clerkenwell. It is on Clerkenwell Road which is between Gray's Inn Rd and Old Street. Nearest main line rail is Farringdon.

You know, I don't think St James' Park did record 30C because I've often seen Philip mention that station in readings during the month, meaning he has access to them immediately rather than at the end of the month. The fact that he only mentions Gravesend at 29.5C (another non-standard site!) suggests SJP got no higher than this.

Kold, re Gravesend... there was a fuss about this in August 2003 when Gravesend reached 38.1C that Sunday. It does seem to record higher temperatures than many other sites.

Edited August 9, 2007 by Nick H

[Spirit of 1740]

You know, I don't think St James' Park did record 30C because I've often seen Philip mention that station in readings during the month, meaning he has access to them immediately rather than at the end of the month. The fact that he only mentions Gravesend at 29.5C (another non-standard site!) suggests SJP got no higher than this.

Indeed and, if true, I don't think anyone can then feasibly argue that 30c was reached in central London under standard conditions. You can hardly get any more central than St James' Park!

[saint]

so we did hit 30c but not officially, i am confused

[West is Best]

This all seems fair enough to me. 30C wasn't officially reached - that's the bottom line I think.

As a footnote we can however add that 30.3C was reached at a non-standard site, that it was probably 30C therefore in some places (whilst not officially!). There are also longer terms issues about urbanisation I think, and I hope to goodness the Met O can get the central London situation sorted together with any other sites that could usefully be improved!

[DR Hosking]

I know this thread has sort of died a death with the general consensus that 30c was not "officially" reached but it was reached at "unofficial" sites. Just read the Met offices August summary and quote "London, Cambridge, Holbeach and Coningsby all recorded temperatures around 30 °C on 5th"

However I cant find any further information on any of these and what temperatures were reached and whether they are official or not?? Any one got access to info I dont who can help?

[Stratos Ferric]

This all seems fair enough to me. 30C wasn't officially reached - that's the bottom line I think.

As a footnote we can however add that 30.3C was reached at a non-standard site, that it was probably 30C therefore in some places (whilst not officially!). There are also longer terms issues about urbanisation I think, and I hope to goodness the Met O can get the central London situation sorted together with any other sites that could usefully be improved!

I think, WiB, that irrespective of how any equipment is screened, super-urban (city centre) locations like London and Birmingham are always going to be unrepresentative.

[Bobby]

No chance of an official 30c now this year. Years without 30c must be rare, espeically these days.

[Optimus Prime]

No chance of an official 30c now this year. Years without 30c must be rare, espeically these days.

Here's a chart showing the highest summer maximum temperatures from 1980-2007 (bearing in mind the 80s had some of the poorest highest summer maximum temperatures of the 20th century)

No real trend taking place. The early and mid 80's was very poor but with a peak during 1989 and 1990. 1991-1993 was fairly normal, before a very hot summer period 1994-1997 with 33c and above being recorded in each summers. 1998-2002 was also unremarkable but with yet another peak in 2003, a decrease then another large peak in 2006 before a very cool 2007 summer low (29.7c max)

Summer 2007 comes in joint 3rd coldest for highest maximum temperature in almost 30 years (with 1993)

So I would anticipate a few more fairly normal years (highest summer maximum around 32.0c) before another whooping summer temperature around 2012.

[West is Best]

No chance of an official 30c now this year.

That's not actually true. Very slim chance, but certainly not no chance.

[Bobby]

That's not actually true. Very slim chance, but certainly not no chance.

Technically, true, but as good as no chance.

[West is Best]

Technically, true, but as good as no chance.

Well I grant you it's unlikely, but today is 10th September. Historically 30C has been recorded still on:

11th

12th

16th

17th

19th

24th

25th

27th

with an honourable mention to the 29.4C on 01st October 1985. 25C's have been recorded through to mid October.

OK, it's unlikely. But even 'as good as no chance' overstates the case, unless you can be definite about the synoptics which are the key. I know I can't be.

[Eugene]

Yes no 30C this year officially and i'm very confident we won't reach 30.0C+ this September.

I think 1947 was the last time we reached 30.0C+ after September 15th.

Edited September 10, 2007 by Eugene

[Eugene]

And that was after a hot summer, which we haven't had this year so mapgie isn't far wrong virtually no chance of it now.

[West is Best]

And that was after a hot summer, which we haven't had this year so mapgie isn't far wrong virtually no chance of it now.

There were a string of warm September maxima in the 100 years up to 1947. It's not got anything much to do with the summer. If the synoptics are right it can happen.

As I say, it's extremely unlikely. It's just incorrect to say 'no chance'. One year there's bound to be another 30C on or after 15th Sept, regardless of the preceding summer.

However, at the moment I think most eyes are on a likely cooldown! I even think my chances of getting 4 more 25C's to win the second half of my bet with TEITS is receding fast.

[Bobby]

No, can never be certain of course, the model outlook does look pretty cool though. I don't think we will see 25c again this year in fact.