It was a good job the Met Office decided on Tuesday to extend their yellow warning for heavy rain northward as most places south of Watford, the M4 and M5 got away with much less than 10 mm in the 06-06 UTC period yesterday. They were correct in saying that the highest totals would be across parts of East Anglia and the Midlands because they were, with Tibenham the wettest of the SYNOP stations with 59.2 mm in the 24 hours. My estimates from weather radar were pretty accurate for Tibbenham (62.3 estimated 59.2 actual), in fact the graphic in which I’ve greyed out totals below 25mm is quite spectacular. I’ve been generating these estimates for ten years now and in that time few people have commented on them regarding their accuracy but over the years I’ve noticed that other weather sites on the web have followed my lead. It’s something I always wanted to introduce when I worked for the Nimbus team at the Met Office but never got the go ahead to do it. At that time the radar team did routinely produce a graphics file of accumulations which was never used in Nimbus. There was no wet bench at the Met Office twenty years ago of course, and rather bizarrely no one thought that a map of accumulated rainfall totals, as opposed to one showing instantaneous rainfall rates, was worth the effort.