UK Extremes: Comparing May 2020 with May 2024

We all remember May 2020.  That gloriously long, hot, sunny month when we were all stuck at home due to the Covid lockdown.  It must have been hotter than May 2024, surely?   Hence so many on social media questioning how this May could have been the warmest on record.

A simple comparison of the two respective months, just looking at the daily UK extremes (as published on the MetO website at the time) is, however quite revealing.  



May 2020

Mean UK Extreme:  11.16c

Mean UK Extreme Maxima: 22.32c
Mean UK Extreme Minima: -0.16c

Highest Maximum Temperature: 28.2c
Lowest Maximum Temperature:  14.2c

Days >= 20c:  21
Days >= 25c: 10

Highest Minimum Temperature: 7.1c
Lowest Temperature: -6.6c

Air Frosts: 15


May 2024

Mean UK Extreme:  13.22c

Mean UK Extreme Maxima: 22.54c
Mean UK Extreme Minima: 3.91c

Highest Maximum Temperature:  27.5c
Lowest Maximum Temperature: 18.6

Days >= 20c:  26
Days >=25c:  4

Highest Minimum Temperature:  7.6c
Lowest Temperature:  -1.1c

Air Frosts: 2



So, taking just the UK extremes (which admittedly may not be representative of conditions across the whole of the UK) we can see that:

May 2024 was warmer both by day and (especially) by night.

May 2020 had many more air frosts - indeed, 2024 had remarkably few.

May 2020 had more days with a maxima above 25c, but also more days with a maxima below 20c

May 2020 was, however, much sunnier.   And that, of course, is why it is remembered as a hotter month.    But the temperature we experience standing in full sunlight in the middle of a field is not the temperature used for climatological purposes - and often the official temperature within a aspirated Stevenson Screen can be higher on a cloudy day than it is on a sunny day.   And a day lasts 24 hours, not just whilst the sun is in the sky ....