Funnily enough I had a quick look earlier at the Davis range of weather stations on a certain online shop - I know they're good quality, but I was surprised to see that they apparently don't need to be in a Stevenson screen (so presumably the Met Office-approved instruments are something else - wonder what brand they use?)

Then you get fan-aspirated options, daytime only or 24-hour and yes - calibration rears its head. The shop says, and I quote:

"Recalibrating the temperature humidity sensor in the field requires a visit to site from someone with a certified accurate sensor. This would need to be a reference instrument with an annual certificate from a UKAS test house. If you need to do this then we consider that it is actually more cost-effective to replace the temperature humidity sensor with a fresh one."

This will, doubtless, be what's happening at Cambridge as we speak (well, maybe on Monday!)

If a national record is to fall everything has to be absolutely 100% certain. Brogdale passed the checks in 2003, it remains to be seen whether Cambridge does as well.

I must admit I thought you were joking when I read this earlier today. No idea that stars and rosettes were dished out for weather stations.

Hello Darren Im not allowed to say, as the calibration firm i worked for made me sign a non/disclosed letter it meant that I worked for 18 months and got paid 5 years money I cant talk about names or certain met equipment I could not turn that down as i got a another job part-time to take me to retirement.

I can confirm the equipment you mention as very good.

The report on the BBC News at Six has a report from the site. TBH it doesn't really clarify things a great deal but there IMO is nothing obviously wrong. The 1.5m rule mentioned (by Retron earlier) could well be passed, but it is difficult to be certain from the angle shown.  

The discussion on here really shows how hard it is to get a precise temperature reading on any sort of instrument, but it makes me wonder, are even 'calibrated' thermos really capable of reading the 'correct' temperature at any given point. Does a ultra precise temperature even exist in the real world?

According to the Met Office WOW website, the botanic gardens in Edinburgh was awarded a gold rosette for last year, but only has a one star rating (presumably because it sometimes takes a long time for sunshine hours data to become available for that particular station as that data isn't instantly available from other sites such as weathercast.co.uk as it is for Edinburgh Gogarbank, for example).

Edinburgh Gogarbank on the other hand, also has a gold rosette for last year, but has a five star rating on the Met Office WOW website.

The BG's twitterer finally awoke from their slumber to issue a tweet.

Might is all depend on whether the gardener trimmed the turf a bit too close?

What I find curious is why the NIAB figure was broadcast immediately without any reservation or caveats, but now we have to have an investigation for the verification BG figure. Is the standard of proof higher for an all time record?

I'm also still interested to know what has happened to Monks Wood and Bedford data.

Yes, I think it can be done. I can certainly sense a .5C change in temperature, good met kit is accurate to .1C.

Was the warmest place yesterday around Cambridge? I wouldn't doubt it*. Is it a place you might expect it to be a really hot day given the state of the atmosphere? Yup. Did the temperature as measured by standardised thermometers reach over 38C in that area? Undoubtedly. Over 38.5C? that is yet to be verified.

Over the years I've seen plenty of maps of the measured temperature of really cold night or really hot days: summer 2003, winter 1995, summer 2016, winter 1981. It's odd that people tend to doubt the hot ones more - we all know why.

*though other measurements from other places may yet turn up.

I take it you worked for a company who do the calibration on equipment used by the Met office and it’s the Met office we feel is lacking, not the companies they outsource to, which I’m sure do what they’re paid to do.  So this isn’t criticism towards you personally, or your company, although I really appreciate that you’ve taken it upon yourself to explain, frustrating as it is for us all.  

It isn’t until times like this that we get to know how things actually work and it shouldn’t really surprise us that another public sector department seems to operate on a wing and a prayer!  But I think it has even though the Met office has been heralded as  ‘the best in the world’.  It isn’t just that one station that we’re questioning, it’s the whole organisation.

I heard that one a bit later this afternoon. I wasn't surprised as I got 37C in my home village of Horseheath just 20 km outsidee Cambridge and Cambridge was always hotter.

Tried to read through all these pages, appears alot of misunderstanding with how the Met Office Readings work

I run the Met Office Climate Station in Brampton, Cumbria 7076 (20 years)

We have a Stephenson Screen, inside most Climate Stations we now have a Vaisala Temperature logger. These were were introduced within the last 18 months as all mercury thermometers were banned by the Met Office. 

Each morning at 10am  (9am in the winter) I open the screen and record  Max,Min, Dry and Wet Bulb, I also have a range of ground equipment to measure aswell. Grass Min and Soil temperatures and rainfall.

This data is then uploaded onto the Met Office site  (WOW)  so you will only ever see my 10am data

We are told only to open the screen at 10am, to avoid unnecessary heat or cold to enter the screen invalidating the readings, hence the delay in lettting everyone know what the record has been. I am guessing then they will check with the observer that he carried out all the correct procedures. If he had a sneaky peek at 2pm it would be invalidated. We all get inspected every few years to check the site is correctly maintained.

Personally a manned Weather Station is best, Met Office did move away from these for a while but have slowly come back again recently when funding allows.

If anyone needs any further information please send me an email.

31.8c for me -  new all time record, timed at 1442hrs

No intention of closing it yet awhile, certainly not until the Cambridge argument has concluded.I'm glad you opened thi as a separate thread, seeing that it's run to 41 pages. Is 41 pages in 2 days a record, too?

Thanks Cax

The Met Office will be in the process of vetting the temperature by checking the recording site and equipment for any potential problems. If it passes  38.7 will reign as the UK's new historic high. 

Just give them a little time  a lot to the job.

Certainly is, especially since Brian doesn't normally allow any MO thread to run to more than around 50 pages (which is only 9 pages more than what is currently on this one) before locking that thread and then starting the next one.

I would imagine that the standard would be higher for an all time UK record which may sit in the annals for years (or maybe not !)

I also imagine the Bookies would need to be convinced they have to pay out on those who bet on the record being broken this year

As well as checking the site and equipment I wonder whether they go back over (say) the last 12 month's daily readings to verify that this site is consistent with a few other local sites and not showing anomalously high or low readings

The Met said on Twitter earlier that there was a problem with the temperature sensor at Bedford due to "current conditions at the site" and it had been switched off!

Would a bet now be valid it is still a form of odds 

That's a good turn of phrase, Essan, and I get your point. However, the suspicion running through all this is lack of adequate checks and validation may make some data inadmissible at a time when exceptional temperature measurements are being recorded. There is a lot of genuine interest in this. Posters may have used a bit of poetic licence - but the scientific reservations are quite proper. We must wait for "due process" but it will be disappointing if it turns out that things were "less well policed" than they should have been. I suggest everyone would like to be proved wrong on that point.

Roger

Well this is an interesting point. Are we suggesting the standards of proof in scientific inquiry are subservient to the requirements of the betting industry.

There have been some fairly impressive sums bet on sporting fixtures which depended a referee's decision, e.g. did the ball cross the line or not, or did the "hand of God" come into play and a penalty should have been awarded. Evidence has show many sporting decisions to be erroneous. But I don't recall those being overturned on appeal. The referee's decision was final.

I don't know if it was even possible to bet on the July temperature record. However, I do question again why is the NIAB July record is not being subject to an inquisition but the CBG national record is? The same scientific standards should apply to both.

Have you been reading this thread? 😀

There are two “official” weather stations in the Cambridge area: the NIAB automatic site just to the north of the city which recorded 38.1C, and a manual station at the Botanic Gardens, which is not run by the Met Office itself but is an approved site. That one recorded 38.7C. However as a manual site it only reports once a day at 10am (0900Z) so the reading wasn’t known until this morning.