National Weather Service United States Department of Commerce

Significant Heat in the Northwest U.S.; Tropical Rainfall Potential in the Southwest U.S.

A significant late season heat wave continues in the interior Pacific Northwest for at least one more day before easing somewhat Friday into Saturday. A combination of monsoonal moisture and tropical moisture ahead of tropical cyclone Lorena will bring a marginal to slight risk of excessive rainfall across the southwest U.S. through Saturday which may bring areas of flooding. 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