Hereinafter, we publish time series of simulated middle Oligocene (~30-25 Ma) and pre-industrial surface temperatures, sea-level pressures and precipitations during boreal winter months (December, January, February). Each file contains the data from the last 100 years of simulations, which were run with COSMOS (ECHAM5/MPIOM/OASIS3). The atmosphere component ECHAM5 was run in the resolution of T31/L19, while the ocean model MPIOM in the resolution of GR30 (bipolar orthogonal curvilinear grid with a formal resolution of ~3.0°x1.8°). The CO2 level is set to 560 ppm (Oligocene_560ppm simulation) and 280 ppm (Oligocene_280ppm and pre-industrial simulations). Paleogeography used in our simulations was compiled by GETECH. More details about a model setup can be found in Walliser et al. (2017, doi: 10.1016/j.palaeo.2017.03.020). Based on these time series we have calculated correlation maps between winter sea-level pressures and local (-5-5°E,45-55°N) precipitation and surface temperature rates. Additionally, we have calculated empirical orthogonal functions of the modelled winter sea-level pressure across the North Atlantic sector (-90-70°E,20-90°N). These data were used to analyze NAO-like variability during middle Oligocene (Walliser et al., 2017; doi: 10.1016/j.palaeo.2017.03.020).