Recently I developed an application that uses the Met Office regional and national gridded data back to 1929. I would have used the whole series but sunshine data has only been gridded back to 1929. Anyway my first stab was to list the summer index using the months June, July and August, the ‘meteorological’ summer and wrote this article about it. Now that summer 2016 is finally and fitfully coming to an end I thought I would extend the application to generate and index for the extended summer May through to September.
1976 loses out to 1959
As you can see from the above chart the results for the extended summer are quite different from those of just June, July and August, some summers like that of 1976 lose their #1 rank and drop to #12, whilst the summer of 1959 jumps up to the #1 slot as the best summers in the UK since at least 1929.
The reason why 1976 slipped so much was that May and September in 1976 were both rather wet and dull over the UK so the index is lower, whilst the May and September of 1959 were much drier than the June and July, and in 1959 sunshine was never in short supply during any of the five months of the extended summer. Below is a ranked list of both highest and lowest summer indices for the UK as a whole, the maximum score is 80 and the minimum score -80 for the extended summer, rather than 48 and -48 for the meteorological summer.
As you can see from the table below the worst summer in the UK since 1929 in both the meteorological and the extended forms was 1954, with an index of -64. The summer of 2016 as you can see is currently joint #17, but only comprises 4 out of the 5 months of the extended summer, so I’ll keep you posted when the September data eventually arrives to see how it performed.
Regionally in 1959 northeast England and the Midlands came out top with an index of 72 out of 80. Scotland didn’t fare quite as well but the indices there were still positive and still relatively high.
In 1976 southeast England had the highest summer index of 48, but Scotland and northern Ireland didn’t score too well.
At a glance
Finally here are a couple of charts that show you at a glance the last 87 summers and how they compared as regards temperature versus rainfall, and temperature versus sunshine.
As you can see 2006 was warmer than 1959 but not drier or sunnier. 1989 was a little sunnier than 1959 but cooler and a little wetter.
I am now glad that I subscribed to the Weather magazine and found these old articles concerning the summer index. It’s a quick and easy way of comparing summers of the past and hopefully I can do the same for winters but that will be a lot trickier.
There are 17 different national and regional areas within the 1910 data series, so it’s not really possible to display all of them in this one blog. Let me know if you would like me to generate you a regional or national table and I’ll email it to you. Of course please let me know if you spot a problem with my maths, after all I have been an ex-metman for almost five years now.