OK, there was about 20 minutes of torrential rain and some thunder on the West side of Shrewsbury from those cells that really grew out of nowhere in the space of 10 minutes. Was finishing off at an allotment , nothing ominous in the sky, mentioned the ‘B’ word, called into the local shop for maybe 5-10 mins and in that time the skies erupted. Annoyed I missed the approach, very unexpected but looks like further East there will be plenty of fireworks later.