The RASM Climate Diagnostics provides time-step averaging output for surface meteorology (PSFC, TSK, PMSL, T2, TH2, Q2, U10, V10), fluxes at the surface (HFX, LH, SWDNB, GLW, LWUPB, SWUPB), and fluxes at the TOA (SWUPT, SWDNT, LWUPT, LWDNT). The averaging can be set by the user with some interval of seconds, minutes, hours, days, or month. The average output file is set to use auxhist5. Additionally, diurnal averaging is provided which creates monthly averages for three hour periods of time during the day (00-03, 03-06, etc.). The diurnal average output is set to use auxhist6. This diurnal averaging output is only created in monthly files (the simulation has to be longer than a month to see the output). The intended application for the RASM Diagnostics is for regional climate simulations and the elimination of the need to produce the high-volume and I/O intenstive instantaneous WRF history files for long duration simulations. namelist.input settings for RASM Climate Diagnostics in &time_control -settings for RASM diagnostic mean output: -flag to turn on the mean diagnostic output (1 = on, 0 = off) mean_diag = 1, -set the time interval for the frequency of mean calculations mean_diag_interval = 1440, (minutes) mean_diag_interval_s = 3600, (seconds) mean_diag_interval_m = 1440, (minutes) mean_diag_interval_h = 6, (hours) mean_diag_interval_d = 1, (days) mean_diag_interval_mo = 1, (month) -use the standard WRF namelist settings for auxhist5: auxhist5_outname = "wrf_mean_d<domain>_<date>.nc", io_form_auxhist5 = 2, frames_per_auxhist5 = 1, Notes: -a time interval must be set -only one of the time intervals can be set (cominbations do not work) -settings for RASM diagnostic dirunal output: -flag to turn on the diurnal diagnostic output (1 = on, 0 = off) diurnal_diag = 1, -use the standard WRF namelist settings for auxhist5 and auxhist6: auxhist6_outname = "wrf_diurnal_d<domain>_<date>.nc", io_form_auxhist6 = 2, frames_per_auxhist6 = 1, Note: The dirunal output is hard coded for three-hourly intervals (8 values in a day) and output in monthly files. Acknoledgement: The RASM Climate Diagnostics for WRF was developed and implemented as a part of the Regional Arctic System Model (RASM) project funded by the United States Department of Energy - Regional and Global Climate Modeling Program. 04 April 2017