The Status of the Weather Radar Acquisition for the Washington Coast

May 13, 2011

Cliff Mass Department of Atmospheric Sciences

University of Washington

Radar coverage for the lowest beam (.5 degree elevation angle) for the current network. Red areas indicate no coverage below 8000 m (25,000 ft). Radar coverage calculations byKen Westrick

YOU KNOW THE PROBLEM!

There Has Been Lots of Movement on the Acquisition and Installation

of the New Coastal Radar

The Location is Decided: Langley Hill

• 3 miles east of Copalis Beach, a coastal town.

• On a 250 ft wooded hill.

On March 18th a lease for the land was signed;  days later construction

was initiated

The Concrete Base for the Tower is In!

The ID will be KGLX

KGLX is also a Gallup, NM Country Music Station

What Will The Radar See?

Coverage at 2000, 4000

and 10,000 ft above the radar site.

Coverage Analysis by UW’s Dr. Socorro Medina

Beam blockage at 0.0° elevation angle for different radar locations(using ~1 km resolution terrain and a 30 m tower)

Beam blockage at 0.5° elevation angle for different radar locations(using ~1 km resolution terrain and a 30 m tower)

Beam blockage at 1.0° elevation angle for different radar locations(using ~1 km resolution terrain and a 30 m tower)

Beam blockage at 1.5° elevation angle for different radar locations(using ~1 km resolution terrain and a 30 m tower)

Beam blockage at 2.0° elevation angle for different radar locations(using ~1 km resolution terrain and a 30 m tower)

We Got A Taste of the Value of a Coastal Weather Radar During

the IMPROVE Field Program in January-February 2001

Westport S-Pol Radar (January-February 2001)

Reflectivity from S-Pol radar at Westport 0031 UTC 2 Feb 2001 at 0.5 degree elevation

dBZ

It will be a used radar!

Why? There was enough money for new!

• A used WSR-88D radar (same as the rest of the network) was available from the Air Force.

• The WSR-88Ds have been modernized over the years.

• The NWS was nervous about maintaining a different radar

• The Langley Hill radar would be refurbished and updated before installation

After Refurbishing

The First (and ONLY) National Weather Service Radar With A Zero-Degree Elevation Angle

Distance-Height Diagram for Zero Degree and Standard 88-D Elevation Angles

Note the absence of low-level coverage of the standard .5 degree elevation angle at greater distances (more than 100 km out). The zero degree angle provides a major improvement in coverage at long ranges

in the critical lower atmosphere.

One of the first dual-polarized NWS radars in the U.S.

Advantages of Polarized Radars

• Can use to determine precipitation type.

• Can be used to determine more accurate precipitation intensity.

• Far better in securing precipitation intensity in complex terrain when there is partial beam blockage.

Schedule

• The tower should be up during June.

• Strong assurances by NWS folks that the radar would be operational by the end of THIS September!

• This will be a neutral ENSO year with the potential for big storms.

Acknowledgments

Senator Maria Cantwell: played crucial role in gaining resources for the radar

Plus The Active Lobbying By a Long List of Regional

Meteorologists, Businesses, Local Governments, Environmental

Groups, and Others.

The End

The right diagram indicates the effective coverage of theWeather Service radars for all elevation angles at 10,000 ft above mean sea level, with hatching indicatingsubstantial blockage.