The U.S. Geological Survey (USGS), in cooperation with DuPage County, Illinois, maintains a Watershed Data Management (WDM) database consisting of hourly dewpoint temperature, air temperature, solar radiation, wind speed data based on the data collected at the Argonne National Laboratory (ANL) and hourly potential evapotranspiration computed from them using the computer program LXPET (Lamoreux Potential Evapotranspiration). Murphy (2005) describes in detail the computer program LXPET. Over and others (2010) describe in detail the development of this database and the analysis and method of processing of those data from January 1, 1948 to September 30, 2003. Bera (2014) describes in detail the update of this database with the processed data through September 30, 2011. This data release is the update of this database with the processed data through September 30, 2014. The primary data for each year is downloaded from the ANL website (http://gonzalo.er.anl.gov/ANLMET/numeric/) and is processed following the guidelines documented in Over and others (2010). References Cited: Over, T.M., Price, T.H., and Ishii, A.L., 2010, Development and analysis of a meteorological database, Argonne National Laboratory, Illinois: U.S. Geological Survey Open-File Report 2010-1220, 67 p., http://pubs.usgs.gov/of/2010/1220/. Bera, M., 2014, Watershed Data Management (WDM) database for Salt Creek streamflow simulation, DuPage County, Illinois, water years 2005-11: U.S. Geological Survey Data Series 870, 18 p., http://dx.doi.org/10.3133/ds870. Murphy, E.A., 2005, Comparison of potential evapotranspiration calculated by the LXPET (Lamoreux Potential Evapotranspiration) Program and by the WDMUtil (Watershed Data Management Utility) Program: U.S. Geological Survey Open-File Report 2005-1020, 20 p., https://pubs.er.usgs.gov/publication/ofr20051020.