WRF 27 km ________________________________________________________________________________ Access - The WRF 27 km archive may be accessed by a ftp client or by a web browser: 1) If you want to use a ftp client, Windows PC users may use WinSCP, FileZilla, etc. that support passive mode. MacOS and Linux users may use the ftp command. Connect your ftp client to ftp.arl.noaa.gov using anonymous and your email address for the username and password, respectively and change directory to /archives/wrf27km. Note if you are using multiple ftp connections, limit the number of concurrent connections equal to or less than two. Otherwise, your access to our ftp server may be blocked off. 2) If you are using a web browser, point it to https://www.ready.noaa.gov/data/archives/wrf27km. It may take a few minutes or longer for the webpage to display. ________________________________________________________________________________ ARL files are available from WRF 27 km model runs with instantaneous and mass coupled time averaged wind fields. The ARL files with mass coupled time averaged wind fields should only be used with HYSPLIT Version 5.0.0 or later. ARL files with instantaneous winds are located in the inst subdirectory and ARL files with mass coupled time averaged wind fields are located in the avg subdirectory. Limited testing has shown that HYSPLIT performs slightly better with the mas coupled time averaged wind fields. The Advanced Research Weather Research and Forecasting (WRF-ARW) model was initialized at 06 UTC each day and run for 42 hours with the first 18 hours discarded as model spin-up. WRF model options: Microphysics scheme: WRF Single-Moment 3-class scheme Longwave and shortwave radiation schemes: RRTMG Surface layer scheme: MM5 similarity Land surface model: Noah Land Surface Model PBL parameterization: UW (Bretherton and Park) scheme Cumulus parameterization: Grell-Freitas scheme Initial and boundary conditions: North American Regional Reanalysis (NARR) Analysis nudging: NARR Observational nudging 1980-1999: NCEP ADP operational global surface (ds464.0) and global upper air (ds353.4) observations Observational nudging 2000-: NCEP ADP global surface (ds461.0) and global upper air (ds351.0) observational weather data WRF grid: WEST-EAST_PATCH_END_STAG = 217 SOUTH-NORTH_PATCH_END_STAG = 175 BOTTOM-TOP_PATCH_START_STAG = 1 BOTTOM-TOP_PATCH_END_STAG = 34 CEN_LAT = 37.00001 CEN_LON = -98. TRUELAT1 = 25. TRUELAT2 = 50. MOAD_CEN_LAT = 37.00001 STAND_LON = -98. POLE_LAT = 90. POLE_LON = 0. MAP_PROJ_CHAR = "Lambert Conformal" eta_levels = 1.000, 0.998, 0.996, 0.993, 0.990, 0.985, 0.980, 0.975, 0.970, 0.960, 0.950, 0.940, 0.930, 0.920, 0.910, 0.895, 0.880, 0.865, 0.850, 0.825, 0.800, 0.775, 0.750, 0.720, 0.660, 0.570, 0.475, 0.370, 0.250, 0.145, 0.090, 0.045, 0.025, 0.000 Additional details of ARL formatted files: Daily files with instantaneous winds are located in the inst subdirectory. Daily files with mass coupled time average winds are in the avg subdirectory. 34 Sigma Levels: 1.0000, 0.99900, 0.99700, 0.99450, 0.99150, 0.98750, 0.98250, 0.97750, 0.97250, 0.96500, 0.95500, 0.94500, 0.93500, 0.92500, 0.91500, 0.90250, 0.88750, 0.87250, 0.85750, 0.83750, 0.81250, 0.78750, 0.76250, 0.73500, 0.69000, 0.61500, 0.52250, 0.42250, 0.31000, 0.19750, 0.11750, 0.06750, 0.03500, 0.01250 27 km horizontal resolution Lambert Conformal Grid 216x174 grid cells Spatial Domain: 13.2321N 122.8906W to 51.8331N 55.6678W Model Type: AWRF Grid Numb: 99 Vert Coord: 1 Pole Lat: 37.86 Pole Lon: -98.00 Ref Lat: 25.00 Ref Lon: -98.00 Grid Size: 27.00 Orientation: 0.00 Cone Angle: 37.86 Sync X Pt: 108.50 Sync Y Pt: 87.50 Sync Lat: 37.00 Sync Lon: -98.00 Reserved: 100.00 Numb X pt: 216 Numb Y pt: 174 Numb Levels: 34 Instantaneous winds in inst subdirectory: Surface Variables: SHGT PRSS TPP1 DIFR PBLH USTR DSWF SHTF LHTF T02M U10M V10M Upper Levels: PRES TEMP UWND VWND WWND DIFW SPHU Mass coupled time averagerd winds in avg subdirectory: Surface Variables: SHGT PRSS TPP1 DIFR PBLH USTR RGHS DSWF SHTF LHTF T02M U10M V10M MSFT MSFV MSFU MUU0 MUV0 MUBA MUPE Upper levels: PRES THET UWND VWND WWND DIFW SPHU TKEN DIFT