load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/wrf/WRFUserARW.ncl"

begin
;---Open WRF output file
  filename = "wrfout_d01_2005-12-14_13:00:00"
  a        = addfile(filename,"r")

  wks = gsn_open_wks("x11","wrf_map")

  mpres               = True
  mpres@gsnMaximize   = True
;---Set resources for a WRF map projection
  mpres               = wrf_map_resources(a,mpres)

;---Create and draw a WRF map.
  plot = gsn_csm_map(wks,mpres)

;---Generate some dummy lat/lon locations
  lat_locs = random_uniform( 28, 48,30)
  lon_locs = random_uniform(-96,-70,30)

;---Options for markers
  mkres               = True
  mkres@gsMarkerIndex = 16
  mkres@gsMarkerColor = "Brown"

;---Attach the markers
  id = gsn_add_polymarker(wks,plot,lon_locs,lat_locs,mkres)

;---Drawing "plot" will also draw attached markers
  draw(plot)
  frame(wks)
end