The guy who tried to kill me last Saturday has done two London marathons, about 12 years ago. He remembers that for one of them, the temperature was at a record high for the running of the race: 19 degrees Celcius. N-n-n-n-nineteen! That's my teeth chattering, not a Paul Hardcastle impression. I think 19 is probably about the coldest I have run in, and that only at about 6am - I don't think I will have finished a run in anything less than 20 degrees.
The Red Cross is sending me a running vest for the big day. I may need leggings and a jersey too.