This data provides monthly average daily total solar resource averaged over surface cells of 0.038 degrees in both latitude and longitude, or nominally 4 km in size. The solar radiation values represent the resource available to solar energy systems. The data was created using cloud properties which are generated using the AVHRR Pathfinder Atmospheres-Extended (PATMOS-x) algorithms. Fast all-sky radiation model for solar applications (FARMS) in conjunction with the cloud properties, and aerosol optical depth (AOD) and precipitable water vapor (PWV) from ancillary source are used to estimate direct normal irradiance (DNI) and global horizontal irradiance (GHI). The DNI and GHI are computed for clear skies using the REST2 model. For cloud scenes identified by the cloud mask, the FARMS is used to compute the DNI. The DNI for cloud scenes is then computed using the DISC model. The data are averaged from hourly model output over 19 years (1998-2016). The PATMOS-X model uses half-hourly radiance images in visible and infrared channels from the GOES series of geostationary weather satellites, daily snow cover data from the NSIDC and mixing ratio, temperature and pressure profiles from the Modern Era-Retrospective Analysis (MERRA-2) dataset. The REST2 model uses hourly aerosol optical depth from MERRA-2 to calculate GHI and DNI; water vapor and other inputs for REST 2 are obtained from the MERRA-2. This dataset was derived from the NSRDB and may be used with the following citation: Sengupta, M., Xie, Y., Lopez, A., Habte, A., Maclaurin, G., & Shelby, J. (2018). The national solar radiation data base (NSRDB). Renewable and Sustainable Energy Reviews, 89, 51-60.