"Stuart Brooks" wrote in message

the rolling 12 month period is higher than any calendar year so far

Missed this point in my last reply, sorry.
The rolling 12 month mean here is 9.2ºC, fractionally lower than the mean
for 1997 (9.43ºC) at this site.
However, a quick glance at the rolling mean from Nov94-Oct95 shows it was
higher still @ 9.6ºC.
Might have a look into all rolling 12 month values to see which comes out
the highest, not being a wizard with spreadsheets it might take some time
though.
I'll try and get back to this thread in a few days time.
Alex.