November was notably mild and dull, and very wet and windy in some parts. It was the third warmest November (in a record from 1910) for the UK and the dullest in a record from 1929. It was also a stormy month, with a series of vigorous depressions bringing heavy rainfall and strong winds that caused significant disruption. These included the first named storms (‘Abigail’, ‘Barney’ and ‘Clodagh’) to affect the British Isles, following a Met Office/Met Éireann pilot initiative to introduce official storm names. The persistent heavy rainfall in November effected a hydrological transformation in much of northern and western Britain. Many rivers that saw depressed October flows yielded exceptional flows in November, associated with floodplain inundations that caused disruption but generally modest impacts. However, the exceptional rainfall eliminated soil moisture deficits in northern and western Britain which, along with the high late autumn river flows, has made many areas highly vulnerable to flooding in early winter (as witnessed in the first week of December). With the highest rainfall occurring across the upland gathering grounds of many major impoundments, reservoir stocks increased steeply (the third largest monthly increase in UK total stocks, in a record from 1995) and were above average in all but a few southern reservoirs. With most rain-bearing systems making only a modest impression in the south, river flows and groundwater levels in the English Lowlands were moderately below average but mostly in the normal range. Overall, the water resources situation is favourable entering the winter.
The full Hydrological Summary can be found here.