May 2013 felt disappointing although in fact mean air temperature was just a little above average; daytime temperatures were just a little above average and night-time temperatures just a little below. Rainfall was well above average so that the running 12-month total remained above 1000mm for the 6th month in a row, a remarkable sequence. There were heavy falls on the 15th (21.4mm) and especially on the 18th (40.8mm), the latter causing extensive flooding in the Durham area. Rainfall intensity was extraordinary on the morning of the 18th with 12.2mm in one hour (08:00 – 09:00 BST) and 10.2mm the next hour.
Professor Tim Burt
Department of Geography