Large data sets used to study the impact of anthropogenic climate change on the 2013/14 floods in the UK are provided. Data consists of perturbed initial conditions simulations using the Weather@Home regional climate modelling framework. Two different base conditions, Actual, including atmospheric conditions (anthropogenic greenhouse gases and human induced aerosols) as at present and Natural, with these forcings all removed are available. The data set is made up of 13 different ensembles (2 actual and 11 natural) with each having more than 7500 members. The data is available as NetCDF V3 files with their content representing an individual month of simulation. Data within that includes diagnostics written at daily, weekly and monthly within the period of interest (1st Dec 2013 to 15th February 2014) for both a specified European region at a 50km horizontal resolution and globally at N96 resolution. The data were generated in support of the European FP7 project - EUropean CLimate and weather Events: Interpretation and Attribution (EUCLEIA). Full details are available within Sparrow et al 2017, Nature Scientific Data.