Put it down to rank bad luck, fella.

Mid-month, the MO was showing a final CET of around 11.5-12c.

With just 12 days left in the month, the CET stood at 10.5c

It was record-breaking warmth (which nobody could have envisaged) that dragged the CET so far up.

The whole comp is around 25% good judgment / 75% good fortune.

These two were posted on the 15th May. I was annoyingly prophetic.

That should be the warmest ever Spring then I think?

Correct Snowman. HadCET confirms this as .04 above 2025.

https://www.metoffice.gov.uk/hadobs/hadcet/data/meantemp_ranked_seasonal.txt 

Yes remarkable consistency.  

That means 8 out of the top 10 warmest springs in the last 350 odd years have occurred in the last 20 years and 5 of those have been in the last 9 years.

Astonishingly fast warm up of Spring in the last 2 decades.

13.59 for the comp to 2 decimals

10.73 for the Spring and a new CET record for the season

Dave.  Can you get the CET for the last 10 days of May and put it in here. It must have been amazing. One 24 hour period was 23.4C or something incredible. What was the last 10 days of the month.  🙂🙂🙂🙂

 There have been not too many full months of any name warmer than that 

2026-05-01  14.4

2026-05-02  12.8

2026-05-03  13.3

2026-05-04  12.1

2026-05-05  10.3

2026-05-06    9.4

2026-05-07  10.0

2026-05-08  11.9

2026-05-09  12.8

2026-05-10  10.2

2026-05-11    7.2

2026-05-12    7.6

2026-05-13    9.1

2026-05-14    8.7

2026-05-15    8.6

2026-05-16    7.6

2026-05-17  11.0

2026-05-18  10.2

2026-05-19  13.0

2026-05-20  14.5

2026-05-21  15.7

2026-05-22  18.7

2026-05-23  18.6

2026-05-24  18.4

2026-05-25  21.8

2026-05-26  23.2

2026-05-27  19.4

2026-05-28  19.9

2026-05-29  17.4

2026-05-30  17.3

2026-05-31  16.0

Last 10 days mean = 19.07C

The week of 22nd to 28th had a mean of 20.0C exactly.

Rob - many thanks for this data; it's absolutely fascinating. I wonder how many months have had as big a spread in the difference between the highest and lowest daily mean. 23.2c down to 7.2c is a walloping 16c range!

Congratulations this month goes to Grandad with a superb win in the monthly competition especially given the topsy turvy month. A virtual bottle of bubbly is on its way to you!

May Leader board

1 Jemblow             3.27

2 Wallaw                3.46

3 WindyWillow     3.53

4 Sussex snow magnet 3.73

5 Caz                      3.83

6 Rick M                 4.28

7 GezM                  4.48

7 Domma               4.48

8 Redmoons          4.55

9 DingleRob          4.63

10 Magda             4.81

11 Grandad           4.91

12 Spring Sun Winter Dread 5.05

13 Scillydave         5.32

14 Lanky               5.41

14 Dickieboy68     5.41

15 Ally Pally Snowman 5.53

16 Stormchaser    5.73

17 Snowshoe        6.19

18 Bolty                6.24

19 Hungry Tiger   6.81

20 SaintSnow       7.01

21 Kendalian        7.03

Thanks as always for running the competition

Meanwhile I was feeling pretty good about halfway through the month what with it having been so cool but looking to warm up a good deal. Never imagined it would go so far beyond what I needed that it became a major negative instead.

I can't deny it's frustrating to very well anticipate the shape of a month (estimated warm-cool-warm) yet still not score well on the CET due to extreme events. If it happens any more times this year I think I'll drop out because at that point I might as well be using a random number generator constrained within realistic bounds.

It's certainly becoming harder, I think, to predict the month ahead as there are definitely more extremes. The only relative certainty seems to be that the month will be above average - the trick is working out how much above average given the background factors. 

Stormchaser I hope that you stick with it - I enjoy your analysis of the month ahead.

I'm amazed I have made it to #3 on the chart, probably downhill from now, no doubt lol.