National Weather Service United States Department of Commerce

Flood Threat For Several Locations Today

The active monsoon season will continue the rest of the week and the flood threat today stretches from the Arizona to portions of the Intermountain West. Meanwhile, a humid and moist air mass ahead of a cold front may result in heavy rain and flooding from the Mid-Atlantic to the eastern Ohio and Tennessee Valleys. Finally, slow moving storms may produce flooding for the central Gulf Coast states. 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