R data files for annual indices of heat of 30 Continental U.S. (CONUS) U.S. military installations from 1990-2019. Daily indices were derived from hourly meteorological estimates from the North American Land Data Assimilation System 2 (NLDAS-2) forcing dataset served as the primary source of weather and atmospheric data. We extracted parameters from NLDAS grid cells containing the centroid of each installation based on shapefiles from the Department of Defense (DoD) Military Installations, Ranges, and Training Areas (MIRTA) Dataset. We calculated relative humidity from specific humidity, temperature, and atmospheric pressure; heat index (HI) from temperature and relative humidity based on a US National Weather Service algorithm; and outdoor WBGT from air temperature, relative humidity, solar irradiance, barometric pressure, and wind speed using the method of Liljegren et al. `daily_indices.Rmd` (328402 observations of 18 variables) contains indices for daily maximum, mean, minimum, and 95th percentile values of temperature (deg F), heat index (deg F), and WBGT (deg C) with urban and non-urban inputs to the Liljegren model. `morning_indices.Rmd` (328364 observations of 5 variables) contains indices for daily 0600 hour (local time) values of temperature (deg F), heat index (deg F), and WBGT (deg C, urban model).

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