Climate is a dominant factor driving the physical and ecologic processes affecting the National Capital Region Inventory and Monitoring Network (NCRN). This project was initiated to inventory past and present climate monitoring efforts in NCRN. In this report, the authors provide the following information: Overview of broad-scale climatic factors important to NCRN park units; Inventory of weather and climate station locations in and near NCRN park units relevant to the NPS I&M Program; Results of an inventory of metadata on each weather station, including affiliations for weather-monitoring networks, types of measurements recorded at these stations, and information about the actual measurements (length of record, etc.); and Initial evaluation of the adequacy of coverage for existing weather stations and recommendations for improvements in monitoring weather and climate."