foo.js

// The call with a callback to self
try {
        winfo = windarea.getWindInfo2(LonLat.lat, LonLat.lon, this.time, wante, wpost);
        //this.drawWind(ctx, p.x, p.y, winfo);
        var MI = GribMgr.WindAtPointInTime(new Date(this.time*1000),LonLat.lat, LonLat.lon,
                  function(){this.drawWindArea(p, poslimit, windarea, ctx)})
        if (MI)
        {
            winfo = new Wind(MI.Speed, MI.Heading);
            this.drawWind(ctx, p.x, p.y, winfo);
        }
        else
        {
            return
        }
        
        
 // The callback caller
  for (index in this.LoadQueue[LoadKey].CallBacks)
      {
        if (this.LoadQueue[LoadKey].CallBacks[index])
        {
          this.LoadQueue[LoadKey].CallBacks[index]();
        }
      }