Project: Hydrological cycle over the Iberian Peninsula, precipitation forecast. - The global atmospheric reanalyses suffer from limitations associated with their coarse spatial resolution; they do not allow adequately resolving small-scale physical processes. In this sense, the main objective of the project is to investigate the ability to produce high-resolution atmospheric fields using mesoscale integrations to resolve the details of small-scale processes. To achieve that objective, measurements from traditional sensors such as soundings, remote sensors (UHF and VHF profilers, GPS or satellites) and estimations by means of numerical models (WRF and WRFDA) have been used with the aim of closing the atmospheric hydrological cycle over the Iberian Peninsula. The outcome of the project is an improved high-resolution quantitative estimate of atmospheric moisture balance over the Iberian Peninsula. This work was supported by grants (CGL2013-45198-C2-1-R and CGL2016-76561-R, MINECO/ERDF, UE). S.J.G.R. is supported by a FPI Predoctoral Research grant (MINECO, BES-2014-069977). Additional funding was received from the University of the Basque Country (UPV/EHU, GIU 14/03). Intensive computational resources used in the project were provided by I2BASQUE. Summary: These data are made available as part of paper: S. J. Gonzalez-Roji, J. Saenz, G. Ibarra-Berastegi, J. Diaz de Argandona (2018) Moisture balance over the Iberian Peninsula according to a regional climate model, Journal of Geophysical Research 123(2):708-729. The dataset holds selected postprocessed files that allow to reproduce all the results in the paper. An analysis of the atmospheric branch of the hydrological cycle by means of a 15 km resolution numerical integration performed using Weather Research and Forecasting (WRF) nested in ERA Interim is presented. Two WRF experiments covering the period 2010–2014 were prepared. The first one (N) was configured as in standard numerical downscaling experiments. The second one (D), with the same parameterizations, included a step of 3DVAR data assimilation every 6 h. Experiment D: -windowed-D-AI: Analysis increments (T2, Q2), 2010-2014 for the D experiment -windowed-wavacurip4paper-D: Netcdf files corresponding to experiment D (using 3DVAR assimilation) and years 2010-2014 holding 3-hourly outputs from the run after selecting the window covering the Iberian Peninsula. Experiment N: -windowed-wavacurip4paper-N: Netcdf files corresponding to experiment N (no data assimilation) and years 2010-2014 holding 3-hourly outputs from the run after selecting the window covering the Iberian Peninsula