In the booklet "The Design of Free-standing Walls", there is a map
showing the speeds that are used for building design in the UK. I
am not going to summarise it (as it is very complex), but here are
a few examples:

London 37
Colchester 41
King's Lynn 44
Newcastle 46
Truro 48
Edinburgh 50
Glasgow 52
Lewis 55

All are in metres/sec, and remember that wind damage is roughly
quadratic in the speed. There is also a varying factor due to the
openness of the terrain.


Regards,
Nick Maclaren.