I recently bought the WxWorx system from Control Vision (makers of the Anywhere Moving Map) and am very happy with the implementation on my iPaq handheld.  I’ve made 4 cross country flights and have successfully dodged any cells by more than 25 miles using it.  However, on my last flight from Bend, OR to Chino, CA I planned to go over the Owens Valley starting at Bishop, CA (BIH) and proceeding south to Palmdale.  The WxWorx showed the route to be clear with only a little precip north of Bishop.  From a little south of Reno it became evident that a very large cell or series of cells had developed just to the south of Bishop with significant lightning showing on the stormscope.  I diverted to the west and continued to watch the storm and the WxWorx display which updated regularly.  It never did show the storm.  I wonder if there are “holes” in the coverage of the Nexrad radar or if the radar is limited in the mountains.  Does anyone know of maps of coverage for Nexrad radar?

After the flight I looked for the antenna sites around this area, and found one near Visalia, CA (west of Bishop in the San Joaquin valley) and another well south at Edwards AFB.  It seems as though the weather in the Owens Valley could very well be shadowed by the Sierras.   What’s disturbing is that the WxWorx radar is supposed to be a composite of all the antenna tilts.  I would think that the radar would at least pick up the large vertically developed storms.  These that I saw were huge, probably extending to 40000 feet.

Any comments?

Thanks in advance,

Hal Woodruff
LIVP