National Weather Service United States Department of Commerce

Heavy to Excessive Rainfall in the Central Appalachians; Severe Weather in the Mid-South; Hot Weather in Southern California

Heavy to excessive rainfall may lead to flooding today over southwest Pennsylvania into northern West Virginia, and western Maryland. Severe thunderstorms are possible this afternoon and evening in the Mid-South and across Eastern North Carolina. An extended period of hot weather is forecast for parts of coastal southern California including Los Angeles from today through Thursday. Read More >

NWR Coverage

 

 


USA MAP


 

Coverage Map Notes

The coverage statistics and maps are calculated using a computer model and station data assuming ideal conditions. Coverage may be 5 to 10 percent below the computer predicted coverage for the following reasons:

  • The computer model is sensitive to antenna performance. Antenna performance is a function of local conditions, causing signals to be stronger signal level in some directions than others.
  • Placement of NWR antennas is dictated by the tower owner, which may result in a less than ideal set up.
  • The antenna may be affected by nearby structures or bodies of water.
  • In some special instances, the antenna may have been intentionally adjusted to be "directional" and provide better coverage to a specific area to the detriment of other areas.
  • Because of variations in local site conditions, the performance of an individual transmitter and antenna may be less than predicted or expected.
  • Seasonal environmental conditions, such as icing or heavy rain, affect performance of a transmitter station and its various components, particularly those subject to continuous weather exposure.
  • The coverage maps are shown in a single color format, which relates to an estimated signal level.
    • White: Signal level of greater than 18dBuV: Reliable coverage