To recap, the months with a mean CET of 19C or more are as follows:

19.7C July 2006
19.5C July 1983
19.2C August 1995

So this month will be at least the fourth warmest since records began and might tie for third place.

In terms of the maximum CET the current figure for July per my estimates is 25.5C

The highest maximum July CET on record is 25.6C in 2006.

The final maximum CET could fall to 25.3C based on current output although I would expect it will not fall that much. So it is on a knife edge as to whether we will manage to equal the figure set in 2006. I think we might just fall short.

My mean temperature so far for July is 20.97C.

This compares with 21.51C for July 2006. So this year will be about 0.5C cooler than 2006.

A gripping finish. Something close to 19.2c to 19.3c would be my call based on Stoneyhurst and Pershore struggling to fully get in on the action at times.

Very gripping.  I think there is a need to beware of arbitrary milestones like the 19.0 barrier.  IIRC, any return in excess of 18.8 brings us the third warmest July of all time, surpassing 18.8 recorded in 1783, and of course the epic 18.7(current fourth place) recorded in July 1976. I think we may be looking at a cool down from the current position as things stand by the month's end as the heat is forecast to be much more concentrated in the SE corner in the last few days of the month, here's an example from the 18z:

I am reminded of 1989 thus far, though the June IMBY this year was not quite as good as that year.  1989 was an incredible summer period that effectively went from May to the end of August, and things were very golden brown that year too. If August can deliver, then to be held close to 1989 would be a huge honour for 2018.  In my book its not all about heatwaves (though I do love them), its about steady sustained unrelenting high pressure and sunny days which wring out the moisture.  This then later in the summer (August) can start to generate the "baked soil effect" of higher than expected maxima on account of dry soil heating up more quickly...

Thanks GW. I knew you’d have more accurate figures and data, as well as sticking to facts.  

This is definitely one of the most exciting months we’ve had in this competition!  Not for the competition amongst ourselves, but for records.  Loving it!    

19.38c is my monthly mean (against a CET of 18.9c). I'm expecting my mean to finish close to 19.8c at the months end (just short of the magic 20c).

My mean of 16.5c in June was 0.4c ahead of the CET of 16.1c. That 0.4c anomoly remains true of this month so far. However, NW England's inability to tap into the heat for long enough will see that anomoly stretch somewhat in the coming week with a CET finish IMO of close to 19.2c.

As Phil eluded a 19.0c finish is a remarkable achievement. 

I think the adjustments are to account for urban heat.  On many occasions I’ve tried googling for CET information but it takes some wading through and I only manage to glean bits.  I tend to make more sense of GW’s explanations and I’m sure he will have a definite answer!  

This CET business sounds like a law unto itself! Secret society - don't ask questions! 

But, I accept it for what it is for the purpose of this competition and leave the vagaries to our resident expert, GW!   

Met Office Hadley       19.4c.    Anomaly    3.4c

Metcheck                    19.53c    Anomaly   3.06c

Netweather                 19.82c    Anomaly   3.33c

Canvey Island 20.8c.  Anomaly   1.86c

Darwen 20.3c    Anomaly   2.64c

Mount Sorrel    20.0c.   Anomaly  2.32c

Mansfield Woodhouse  19.3c  Anomaly  1.3c

Peasedown St John 20.71c.  Anomaly   2.17c.

Mean of 10 Stations     19.79c. 

My criticism of the cet is that it doesn`t accurately reflect the average temperature for the country(England). The south I believe does not have a cet station they all seem to be in the midlands/north.This month most of the south say below the m4 will easily record amean in excess of 20c with many places above 21c. It doesn`t seem possible the official cet may not reach 19c after such a baking hot month

But isn't the whole point of the CET to be representative of central England? And central England geographically means the midlands and certainly pushing into northern England. Bournemouth or London shouldn't be included in the series any more than Carlisle or Berwick.

I don't think northern England is part of central Emgland at all. When I first read about the CET back in the 1970s when I took geography 'A' Level, I believe the idea was to contain stations within a triangle London/Bristol/Birmigham (but not including those places, for obvious reasons). This was to avoid both large urban conurbations and proximity to maritime locations. It certainly did NOT include northern England, and it most certainly did not include a station in Lancashire a stone's throw from Blackpool, for heaven's sake!

I'm going to find out about the stations used for the CET in the 1970s, covering the summer of 1976. I will be very interested in their location. But certainly the current selection as far as I'm concerned is a bit of a joke. And please, I didn't get a First in geography now to be told that Lancashire is in central England, WHICH IT ISN'T.

Phew. Back to the beer.

Well yes. Actually the point of the CET is to be the world’s longest running climate record. Gives us a unique insight into current weather with the perspective of several centuries. No other record, least of all the E&W series that start in 1910, get close to this long term view. So the numbers are relative.

From a cursory look at St James’s Park figures I estimate the Central London temperature for July to date as 22.06C.

Completely agree.

I will find out the locations of the CET stations from the 1970s (covering the warm summers from that decade). I doubt whether in the hot summers of 1976 and 1995 for instance a CET station was located in Lancashire. But we shall see.

EDIT: The following paper from the hadobs site gives some background information for the CET stations used over time. It appears that stations have been used from both central England and NW England, presumably to avoid large urban and industrial areas:

www.metoffice.gov.uk/hadobs/hadcet/Parker_etalIJOC1992_dailyCET.pdf

It is worth bearing in mind that Professor Gordon Manley spent the best part of his entire career painstakingly constructing and validating  this series back from the present day to 1659 (for monthly averages at least).

This is a remarkable achievement when considering that instrumental data only takes you back to about 1850 and the rest has to be assembled from a myriad of paper journals and diaries (and the like) and using records that are consistent with one another to give a coherent collection

I just don't know whether he could have chosen different areas such that the whole country could have been covered but my guess is that he would have been severely constrained by what was available in order to get a consistent and coherent data series of any description

Lancashire isn't central England, but London and Bristol certainly aren't either, so why expect more stations in the south while simutaneously criticising the fact that Stonyhurst is included? Somewhere like Manchester is more central to England than either London or Bristol, so why would a triangle including either of those places be any better or more reflective of central England? Answer: they wouldn't.

I think the issue here really is some southerners are upset that the less hot conditions in the rest of England will ruin the chances of a 19C+ month, but that just reflects what conditions have been like in most of the country. 

I find that sometimes its people's CET guesses (being higher or lower), rather than their locations, that tend to drive their comments.

Tonight's update on the CET

Today's figure by my calculations is 20.58C

The running CET mean now stands at 19.14C

I expect the CET to peak at 19.32C on Friday.

The final figure is expected to be 19.09C based on the latest output. 

Those last four days make a big difference. If the heat was to hold on until Tuesday then a 19.5C CET would be very likely. As it is we may have to settle for 19.1C.

Lets be honest. NW England is letting the side down. For millions of us in the UK this is incredible. No excuses Stonywhatever...pull your weight. :)

Stonywhatever struggled up to a measly 20C today!