Isn't the max temperature largly controlled by the sunshine exposure
especially during the summer months ? .restricted exposure ,south facing
gardens ,and all the usual problems experienced by the amateur urban
enthusiast,of which there are many on this group I suspect.

Yes, the max temperatures generally follow the point of highest sun with a
slight lag though during December and January the time of max temperature
has a tendency to go all over the place.

Time of minimum temperature is far less reliable, even in a summer month if
the weather is unsettled.

Oh for the joys of living on Exmoor.....

I don't know, I live near the south coast of Devon east of Exeter so there
is also a sea breeze element to take into account.
________________
Nick.
Otter Valley, Devon
83 m amsl
http://www.ottervalley.co.uk