It was -6c here in Reading last night. (I hear it was colder in some parts of the UK).
This temperature has meant a good part of the lock cutting has completely frozen over - something I've just seen for the first time this morning, a few minutes ago.
The lock cutting is relatively still, at least compared to the main stream, but its still somewhat impressive that it has frozen over with a 1cm thick layer of ice, bank to bank for a good 30m or so.
I'll try and pop outside a little later and get a photo...