This thread is for all comments, discussion and analysis of temperatures in the UK during June, with particular emphasis on the Central England Temperature (CET), for the simple reason that it is the longest running temperature series in the world with over 360 years of data. But you can comment on any interesting temperature statistics or data from across the UK, including your own back yard.

May has been a rather cool month and will finish slightly below average.

For those taking part in the competition all CET predictions for June should be sent directly to me via the forum private message system. Do not post them directly into the thread.

The deadline for predictions this month is 2359 on Sunday evening (2 June). 

Now on to some data for June:

Historic CET summary for June

1971-2000 14.1C (30 years) 

1981-2010 14.5C (30 years)

1999-2018 14.8C (last 20 years) 

The last two Junes have been very warm with 16C CET returns. Those were the first years the May CET was above 16C since 2003. We had a number of cool Junes in 2011-2013 and 2015 with returns between 13.5C and 14C.

Here is a chart of the June CET for all years since 1961:

Direct link to larger version of the chart

Latest model output 850hPa temperatures - 30 May 

GEFS (12z) - hot initially then turning quite cool for about 4 days before turning much warmer again, potentially hot although a lot of scatter from 8 June.

http://www.wetterzentrale.de/de/show_diagrams.php?model=gfs&var=2&geoid=49069&lid=ENS&bw=

GEM ENS (00z) - similar picture to the GFS 

http://www.wetterzentrale.de/de/show_diagrams.php?geoid=49069&model=gem&var=2&run=00&lid=ENS&bw=

Multi Op (00z) - good cross model agreement. The 0z GFS did not go warm in FI

http://www.wetterzentrale.de/de/show_diagrams.php?model=multi&var=2&geoid=49069&lid=OP&bw=

The 12z ECM ENS T2m temperatures for De Bilt show only a brief cool down after the weekend but less heat later in the run than the GFS. There are  a few hot runs but not many.  

http://cdn.knmi.nl/knmi/map/page/weer/waarschuwingen_verwachtingen/ensemble/detail/ensemble-verwachtingen-detail10.png

Met Office contingency planners outlook 

Probabilities for both June and the summer suggest an increased likelihood of a slightly warmer than average period.

https://www.metoffice.gov.uk/binaries/content/assets/metofficegovuk/pdf/business/public-sector/civil-contingency/forecast-temp-jja-v1.pdf

Temperature analogues

Last month the analogue signal was slightly out but not by much. It signalled something between 11.6C and 12.1C as being most likely. The final figure may be 11.2C.

This month I am looking at years with Apr and May CET figures similar to this year and including March where possible. Taking the Apr and May figures the best matches since 1948 are 1948, 1961, 1993, 1995, 1997, 2005, 2010 and 2015. Generally the June CET was close to or slightly above average in these years ranging from 13.5C to 15.5C. If we ignore the outliers we have a range of 14.0C to 15.2C.

The best matches for Mar-May are 1948, 1997 and 2005. These years had a CET of 13.5C, 14.1C and 15.5C. So that is not very helpful. 

If we include the Feb CET as well the best match is clearly 1997. All four months are very close to 2019. 

So the analogues suggest the June CET may be close to the 1971-2000 and 1981-2010 means - i.e. 14.0C to 14.5C. There is a not insignificant chance of something a bit warmer at or just above 15C.

First look at June temperature tracker  

The tracker is suggesting we could be close to 15C by the 13th. So that would imply the CET could end well above the analogue range. The potential is certainly there for quite a warm month but there is a lot of uncertainty as the long models have been flipping around quite a lot in recent days. So confidence is low at the moment.

Thank you for the CET Thread GW  Have prepared my mean of 10 and awaiting tomorrow. 

Met Office Hadley         17.1c.      Anomaly       4.3c. Provisional to 1st.

Metcheck                      17.54c.    Anomaly       3.39c.

Netweather                   18.16c.    Anomaly       4.07c.

Mean of my 10 watched stations    17.85c.   Difference  2.52c. Using a 6 - Year  Average.

Hi GW, your 1971-2000 and 1981-2010 average lines are the wrong way round on the graph! Was just working out how come the later 30 year average was 0.4C cooler... 

Met Office Hadley         17.1c.    Anomaly      4.2c. Provisional to 2nd.

Metcheck                      16.72c    Anomaly       2.57c

Netweather                   18.02c    Anomaly       9.93c

Mean of my 10 stations 16.27c.  Difference  0.94c.     

The drop in temperatures.

Met Office Hadley           16.1c.      Anomaly     2.9c. Provisional to 3rd.

Metcheck                        15.89c     Anomaly     1.74c

Netweather                     16.79c     Anomaly      2.7c

mean of my 10 stations    15.45c.    Difference    1.2c. 

Met Office Hadley           15.4c.       Anomaly      2.2c.  Provisional to  4th.

Metcheck                        15.18c      Anomaly      1.03c

Netweather                     15.92c      Anomaly      1.83c

Mean of My 10 Stations    15.2c       Anomaly      -0.13c.  

After a warm start the CET is taking a big hit. We are currently in a period of potentially 10 consecutive days of below average temperatures. That is not as long and the anomalies are not as big as we saw in early May. Potential signs of things turning warmer by the middle of the month at which point the overall mean may lift back above average.

As usual the official provisional Hadley figures are way too high. Already 0.54C above my estimate. So take the Hadley numbers with a large pinch of salt.

Ah, bloody hell. Was away and forgot all about this. Can you still miss a month and continue with a score given by some mathematical formula?

Met Office Hadley          14.9c.       Anomaly        1.7c. Provisional to 5th.

Metcheck                       14.80c      Anomaly        0.65c

Netweather                    15.39c      Anomaly        1.3c

Mean of my 10 stations    14.64c     Anomaly        0.69c.    

Come on then, what would it have been?  I’ve gone for 15.5c 

Met Office Hadley          14.4c       Anomaly      1.2c.   Provisional to 6th.

Metcheck                       14.56c     Anomaly       0.42c

Netweather                    15.05c     Anomaly       0.96c.

Mean of My 10 Stations   14.31c.    Anomaly       -1.02c.   

It has dropped so rapidly this month!

It will be interesting to see where everybody's predictions fell. Hopefully that'll be out soon.

The temperature has been falling since day one.

Met Office Hadley        14.1c.      Anomaly      0.8c. Provisional to 7th.

Metcheck                     14.26c     Anomaly      0.11c

Netweather                  14.75c     Anomaly      0.66c

My 10 Watched Stations  14.63c.  Difference    -0.7c.   Using a 6 Year Average of 15.33c.   

Continuing cool or cold for the next week as the CET dips down to just 13C.

But there are still signs that it could turn a lot warmer in the second half of the month. But then we had this signal in May and it never really materialised. Maybe this month will be different.

Hadley is currently 0.46C above my CET estimate to the 7th.

IMPORTANT ANNOUNCEMENT - PLEASE READ CAREFULLY

I am going to make a few changes to the competition for the second half of the year. The reason being that the predictions are becoming almost too predictable and with very little spread.

So with immediate effect I will not be publishing any forward looking analysis before the prediction deadline. Too many people now seem to be picking a figure within my analysis range, as you will see when I post the June predictions. I will still publish the analogue and other analysis but only after the deadline. Only the raw historic data will be published in advance.

The deadline for predictions is going to move back to the last day of the month with immediate effect. I will still allow predictions up to the 2nd of the following month but penalties will be reintroduced for predictions made after the end of the month. No exceptions. You don't need to wait for the thread to be opened as all predictions are by PM and can be made at any time. So there should be no excuses.

Here are the predictions for June. All too predictable it would seem. This has to be one of the narrowest spread of predictions ever I think. See rule changes above for July onwards.

Link to full size table

Thanks GW

All seems like fair play to me.

How's the competition going to the end of May?

Thanks GW.

Yes indeed if you think changes need to be made, I’m happy with whatever you do and as Bertie says, it’s fair play!   

I'm not sure what the problem is here. You publish analysis that suggests the CET may be this that or the other, then complain when people take that advice and post their predictions accordingly??

Anyhow from what I recall of the predictions so far this year they have been pretty wide. June does look pretty tight though but I suspect that's just a one off. You will notice that I'm seriously at the bottom of the pile there, no just going with the averages for me!

Still, it's your competition and you can run it how you want. However if this gets too 'heavy' and descends into arguments over rules then I'm out of here, can't be arsed with all that.

My tactic of going for a really warm value hasn't worked for me recently, so I have gone for a much cooler value this time.

Given the manner in which this month is panning out at the moment though, I have a feeling that even my latest much cooler guess might be too high this time.

I know that this isn't the moaning thread, but it is just like the thing that this is happening just now during this complete non-event which is known as our "summer", otherwise I'm sure that everything would probably be coming out much warmer than what it is just now, especially if we were in our winter just now.

You'd be cutting your nose off to spite your face if you did that Col. You're in a good position.

I support the changes GW. A good move IMO 

I support GW's rule change too. To be honest I thought it a bit strange that he was effectively almost recommending what your guess should be; I think it's better if everyone figures it out themselves, whether that be by pattern matching, model watching or finger in the air! 

Totally agree with all the above comments. Actually, I don't really mind what GW's rules are- I'll play by them because it's a really enjoyable  part of each month and it doesn't cost me a short cross penny. And Col- you're good at this- lead us on!