[2] The conterminous United States consists of all the states except Alaska and Hawaii.

[3] These 175 radars included 115 for NWS, 44 for the Air Force, and 16 for FAA.

[4] Available means the time that the system is operating satisfactorily, expressed as a percentage of total time.

[5] The other two major system acquisitions are the Advanced Weather Interactive Processing System (AWIPS) and the Next Generation Geostationary Operational Environmental Satellite (GOES Next).

[6] Doppler radar is used to determine the speed and direction of rain or snow particles, cloud droplets, or dust moving toward or away from the radar. The radar accomplishes this by sending out a pulse using a stable frequency and then measuring the changing frequencies as the distances between the radar and the object changes.

[7] The Air Force and FAA totals cover their respective NEXRADs and 2.7 percent and 20 percent, respectively, of NWS' NEXRADs due to a cost sharing arrangement agreed to by the three agencies.

[8] CONUS consists of all the States except Alaska and Hawaii.

[9] The 10,000 foot level is significant because this is the elevation at which the coverage range of an individual NEXRAD is measured. The ascending radar beam loses its reliability about 125 miles from the radar. At this distance the lowest part of the beam is approximately 10,000 feet off the ground. Therefore, each radar has a coverage diameter of 250 miles. The 250 mile cylinders were the basis for siting NEXRADs to ensure adequate CONUS coverage.

[10] The Air Force owns the RDAs and RPGs associated with each DOD NEXRAD. The PUPs are owned by the Air Force, Navy, and Army since all services are users of the weather data.

[11] Weather support policy is established in the Office of the Chief of Staff of the Air Force.

[12] These commands include (1) Air Combat Command, (2) Air Education and Training Command, (3) Air Mobility Command, (4) Air Force Material Command, (5) Space Command, and (6) Pacific Air Forces.

[13] At the request of the House Committee on Science, Space, and Technology (now the House Committee On Science), the Secretary of Commerce commissioned this review by NRC's NWS Modernization Committee to ensure that NWS complies with the Weather Service Modernization Act (Public Law 102 567), which requires, among other things, that the Secretary of Commerce certify that there is no degradation of service resulting from office closures associated with the modernization.

[14] These figures include three NWS and three Air Force systems used for training, research, and logistics purposes.

[15] NWS added NEXRADs at (1) Greer, South Carolina, (2) Jackson, Kentucky, and (3) the NOAA National Severe Storms Laboratory in Norman, Oklahoma. Also, NWS assumed ownership of an Air Force NEXRAD because Loring Air Force Base, Maine, is closing.

[16] The Air Force canceled the NEXRAD scheduled for Nellis Air Force Base, Nevada. It added a NEXRAD at Fort Polk, Louisiana. It also transferred ownership of the NEXRAD at Loring Air Force Base, Maine, to NWS.

[17] FAA added a NEXRAD at South Shore, Hawaii.

[18] These figures include three NWS and three Air Force systems used for training, research, and logistics purposes. NWS and the Air Force will deploy 116 and 22 CONUS based operational systems respectively.

[19] NWS added NEXRADs at (1) Greer, South Carolina, (2) Jackson, Kentucky, and (3) the NOAA National Severe Storms Laboratory in Norman, Oklahoma. Also, NWS assumed ownership of an Air Force NEXRAD because Loring Air Force Base, Maine, is closing.

[20] The Air Force canceled NEXRADs scheduled for Grissom Air Force Base, Indiana, and England Air Force Base, Louisiana, due to projected base closures.

[21] The Air Force canceled the NEXRAD scheduled for Nellis Air Force Base, Nevada. It also added a NEXRAD at Fort Polk, Louisiana, and transferred ownership of the NEXRAD at Loring Air Force Base, Maine, to NWS.

[22] These budget constraints arose because radar unit cost increases associated with the comprehensive settlement prevented the Air Force from buying as many radars as originally planned while still staying within its program budget.

[23] Program office officials stated that FAA and the Air Force deleted requirements for three and one radars, respectively, because justification for the original requirements was later invalidated.

[24] The five sites are (1) Georgetown, Bahamas, (2) Grand Turk, British West Indies, (3) South Shore, Hawaii, (4) Kohala, Hawaii, and (5) Nome, Alaska.

[25] The actual unit cost estimate is not disclosed in this report because the information may be acquisition sensitive.

[26] Preparation and Submission of Budget Estimates, July 1994.

[27] The NEXRAD Joint Operational Requirements define availability as the time that the system is operating satisfactorily, expressed as a percentage of total time (the time the system is operating satisfactorily plus the time the system is down). Downtime includes corrective and preventive maintenance time and delays encountered due to the delivery of needed spare parts. Most definitions of availability exclude scheduled downtime, such as preventive maintenance.

[28] Command, Control, Communications, and Computer Data Reporting Problem Process Action Team Summary Report, October 1994.

[29] The requisitioning process through the Sacramento Air Logistics Center is required for financial tracking purposes.