[tetrep]

What's your source for areas of the U.S. without doppler? It looks like NEXRAD dopplers are "everywhere" in the U.S.

https://en.m.wikipedia.org/wiki/NEXRAD

[tjohns]

It's not for NEXRAD. The frequencies in question are used for Terminal Doppler Weather Radar (TDWR), which is a special radar used for detecting windshear and higher resolution precipitation data at select airports.

See: https://en.wikipedia.org/wiki/Terminal_Doppler_Weather_Radar