National Weather Service United States Department of Commerce
Clark County, NV, is one of the first counties to adopt Partial County Alerting. NWS Las Vegas requested the change because Clark County is one of the largest in the country with a heavy population density in Las Vegas and low population in other areas. Because NOAA Weather Radio (NWR) is county based, even if only a small part of a county is forecasted to be impacted by a storm, the entire county is alerted, resulting in over alerting. This over alerting strongly impacts large counties. The NWS has received complaints about receiving "too many EAS alerts" for a given county and "too many warnings which are not applicable to my area of the county." Similarly, broadcasters have expressed concerns about NWS requests for EAS activations for warnings that do not apply to their broadcast service area.
NWS Las Vegas has coordinated with Emergency Managers, the Nevada State Emergency Communications Committee, broadcasters, state and local government officials, EAS encoder/decoder manufacturers, and NWR receiver manufacturers to allow the office to use partitions for the following warnings:
  • Dust Storm Warning (DSW)
  • Flash Flood Warning (FFW)
  • Severe Thunderstorm Warning (SVR)
  • Tornado Warning (TOR)

NWS Official Service Change Notice for Clark County, NV 

More Information

Clark County, NV information:

Former NWR and EAS Dissemination Footprint Flash Flood Warning

This Warning, (depicted in green), currently activates NWR Specific Area Message Encoding (SAME) and EAS for the hatched area.

NWR and EAS dissemination footprint Flash Flood Warning as of June 1, 2021

This Warning now activates NWR Specific Area Message Encoding (SAME) and EAS for hatched area.