The lowest beam from the Portland radar (located on Dixie Mtn. The “partial coverage” refers to some blocking by mountains in the Coast Range. A closer view shows the situation here in Oregon: That was just put in 4 years ago after a years-long lobbying effort by a group up there. Note there IS a radar on the Washington Coast. Even for the optimistic 10,000 ft coverage, the Oregon coastal zone is poorly served compared to the California, Gulf of Mexico, and Atlantic coastal regions. where blockage by terrain is significant. Radar coverage near the surface is far poorer, particularly over the western U.S. These radar coverage maps are valid at 10,000 ft ABOVE THE RADAR SITES (many of which are already thousands of feet above the surface!), not at the surface. A second image with a blow-up of the Northwest section is also provided. Under perfect conditions, the maximum range of the WSR-88D for wind information is 230 km (138 miles) and for precipitation sensing roughly twice as far.Īn official National Weather Service map of national weather radar coverage (for precipitation) is shown below. Furthermore, the height of the radar beam increases with distance from the radar–resulting in an inability to see important low-level features at distances from the radar. Terrain blockage is important in mountainous regions like the Northwest.
The range of useful radar coverage is controlled by a number of factors. Such units, known as WSR-88Ds or NEXRADs, describe precipitation and winds in their environs and have revolutionized forecasting and meteorological research. The National Weather Service completed a major modernization in the 1990s, a central component being the installation of powerful Doppler weather radars across the country. #3 happened in the mid 1990s at Lincoln City, and #4 just happened January 16th this year in Lane County (near Eugene). NOAA’s Pacific Fleet is based in a location (Newport) with no good radar coverage…that’s a huge surprise.A tornado or squall line with damaging winds could move through the Eugene or Roseburg areas with very little indication on radar.A tornado or squall line can roar ashore in Lincoln City, Newport, Florence, or Coos Bay with no warning.How is it possible Oregon’s 2nd largest city (Eugene) has no coverage below 10,000′?.The central and southern Oregon coastline has no radar coverage below 10,000′ almost all cool-season weather happens below that elevation.
I’ve blogged about it numerous times and Professor Cliff Mass up at the UW in Seattle has been pushing it for years too. Local forecasters (private/public/media) have known about it for years. In fact there is no radar located along our coastline.
The Oregon Coast has the WORST coastal radar coverage anywhere in the lower 48 states and it’s time to change that.
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