See the NOAA Coverage Maps
and you can see where the 'dead spots' are. (Nevada has a lot of them!)
Anyone looking at weather radios should also be familiar with NWR Specific Area Message Encoding (SAME)
as that is a way to use the alert features on some radios.
The content on these stations are updated periodically by local NWS offices. The trend has been from recorded tape loops to computer generated voice readings. I see that the Reno office is now providing weather briefings via internet - slideshows using Flash.
If you are in an area subject to severe weather events such as tornadoes, then a SAME receiver with good controls for alerts can be valuable.