Will this year follow suit or will we have a May of yesteryear? It's been 30 years since a sub 10c May so who knows.

Here's the headline data:

The all-time CET average is 11.24

1991 - 2020 Average          11.91

May changes between all-time and 1991 - 2020 is  0.67c

May has the second most minor change between all-time CET and the 1991 – 2020 average.

All-time warmest

1833  15.10

2024 14.1

1848  13.90

1758  13.80

1788  13.80

All time Coldest

1698    8.5

1740    8.6

1817    8.7

1855    8.8

1879    8.9  & 1885,1902

Warmest 1991 - 2025

2024  14.1

1992  13.6

2008  13.4

2018  13.3

2017  13.3

Coldest 1991 - 2025

1996    9.2

2021   10.1

2013  10.5

1991  10.7

1994  10.7

2010  10.7

Please send all predictions (with your TWO handle so I know who you are!) to

[email protected]

My prediction is for a warm and wonderful 12.95c

12.0C. 🙂🙂🙂

Thanks Gavin 😊 

It reminded me alot of May 1996 having lived through that one as a weather stat loving kid ! Possibly as close as we can get to it now 

I'd love to take the credit it for it SSWD but it's an updated copy and paste from an earlier one in the competition's history!  

Good spot on the missing 2021 cold year - I've added it to the list.

There's a suggestion of HLB popping up and impacting us for periods of time, with winds from northerly and/or easterly quadrants.  That means cooler days and clearer skies in the west overnight.

I've still gone for a bit above average - because surely the run of ridiculously high monthly CET anomalies can't continue...  (but I said that Feb, Mar & Apr and was wrong!!)

Yes at one point April was looking like it could have been quite a cool month.  But it just never quite happened.  And it ended up very warm again. Similar signs that May could start cool after today's heat. But heat is already starting to build in southern Europe.  So if we can tap into it at some point it could end up very warm.

14.4 to the 1st

3.3c above the 61 to 90 average

3.9c above the 91 to 20 average

13.6 to the 2nd

2.5c above the 61 to 90 average

3.1c above the 91 to 20 average

13.5 to the 3rd

2.4c above the 61 to 90 average

3.0c above the 91 to 20 average

13.1 to the 4th

2.0c above the 61 to 90 average

2.7c above the 91 to 20 average

12.6 to the 5th

1.5c above the 61 to 90 average

2.1c above the 91 to 20 average

12.1 to the 6th

0.9c above the 61 to 90 average

1.5c above the 91 to 20 average

That's a sharp drop. 🙂🙂🙂🙂

11.8 to the 7th

0.6c above the 61 to 90 average

1.1c above the 91 to 20 average

11.8 to the 8th

0.7c above the 61 to 90 average

1.0c above the 91 to 20 average

Bolty I'm missing a prediction from you i think - apologies if you sent it through.

May CET Predictions 2026

Grandad            13.5

Domma             13.4

WindyWillow     13.3

Redmoons         13.25

Caz                     13.2

DingleRob          13.1

Sussex snow magnet 13

Scillydave           12.95

Jemblow             12.8

Dickieboy68        12.68

Snowshoe           12.6

Ally Pally Snowman 12.6

Spring Sun Winter Dread 12.6

Rick M                 12.55

Stormchaser        12.53

Wallaw                 12.45

Kendalian             12.3

GezM                   12.25

Lanky                   12.24

Hungry Tiger       12

Magda                11.9

SaintSnow          11.75

Bolty

May CET             11.24

11.9 to the 9th

0.8c above the 61 to 90 average

1.0c above the 91 to 20 average

11.7 to the 10th

0.6c above the 61 to 90 average

0.9c above the 91 to 20 average

11.1 to the 11th

0.2c above the 61 to 90 average

0.1c above the 91 to 20 average

Yesterday's 00z GFS gave me an estimate for the CET as of 27th May in the mid-11s, slightly below the 1991-2020 average. The warmer weather was fairly subdued in that run, the peak being just a couple of days with a mean max in the low 20s.

Today's 00z GFS is a different story with a run of 7 days reaching the low-mid 20s (and the 28th heading into the high 20s), making for a CET to 27th in the low 12s, around half a degree above average.

11.0 to the 12th

0.1c below the 61 to 90 average

Bang on the 91 to 20 average

10.9 to the 13th

0.3c below the 61 to 90 average

0.1c below the 91 to 20 average