The picture in post 89 reminded me of a problem encountered in the snow of Dec. 2010.
This could even be the same ambulance.
It seems it was on a shout to Belgrave Road, near Howard's house. Following a slight bump (there's minimal damage to the N/S front) the crew found it was stuck and so had to be abandoned.
Looking at the second picture it would also seem help was to hand ; but look at the snow on the recovery truck and his tyre tracks - apparently he got stuck as well!