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/csm/contributed.ncl"

begin
  f     = addfile("uv300.nc","r")
  u     = f->U(1,::4,::4)
  v     = f->V(1,::4,::4)
  speed = u                     ; Sneaky way to copy metadata
  speed = sqrt(u^2+v^2)

  wks = gsn_open_wks("ps","overlay1b")

;---Resource list to hold common resources.
  res          = True
  res@gsnDraw  = False           ; don't draw
  res@gsnFrame = False           ; don't advance frame

  mpres    = res
  cnres    = res
  vcres    = res

  map      = gsn_csm_map(wks,mpres)
  contours = gsn_csm_contour(wks,speed,cnres)
  vectors  = gsn_csm_vector(wks,u,v,vcres)

;---Overlay vectors and contours on map
  overlay(map,contours)
  overlay(map,vectors)

;---Drawing the map will draw contours and vectors too.
  draw(map)
  frame(wks)

end