Aggie Doppler Radar

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The current Aggie Doppler Radar dish ADRADnew.jpg
The current Aggie Doppler Radar dish
The Aggie Doppler Radar in operation atop the Eller O&M Building at Texas A&M University during a rare southern Texas snow storm on February 23, 2010 Eller OM ADRAD snow.jpg
The Aggie Doppler Radar in operation atop the Eller O&M Building at Texas A&M University during a rare southern Texas snow storm on February 23, 2010

The Aggie Doppler Radar (ADRAD) is a Doppler weather radar located on the roof of the Eller Oceanography & Meteorology Building on the Texas A&M University campus in College Station, Texas.

Pulse-Doppler radar radar system

A pulse-Doppler radar is a radar system that determines the range to a target using pulse-timing techniques, and uses the Doppler effect of the returned signal to determine the target object's velocity. It combines the features of pulse radars and continuous-wave radars, which were formerly separate due to the complexity of the electronics.

Weather radar radar used to locate and monitor meteorological conditions

Weather radar, also called weather surveillance radar (WSR) and Doppler weather radar, is a type of radar used to locate precipitation, calculate its motion, and estimate its type. Modern weather radars are mostly pulse-Doppler radars, capable of detecting the motion of rain droplets in addition to the intensity of the precipitation. Both types of data can be analyzed to determine the structure of storms and their potential to cause severe weather.

Texas A&M University Public research university in College Station, Texas, United States

Texas A&M University is a public research university founded in 1876 and located in College Station, Texas. In 1948, Texas A&M University became the founding member of the Texas A&M University System. As of 2017, Texas A&M's student body is the largest in Texas and the second largest in the United States. Texas A&M's designation as a land, sea, and space grant institution–the only university in Texas to hold all three designations–reflects a range of research with ongoing projects funded by organizations such as the National Aeronautics and Space Administration (NASA), the National Institutes of Health, the National Science Foundation, and the Office of Naval Research. In 2001, Texas A&M was inducted as a member of the Association of American Universities. The school's students, alumni—over 450,000 strong—and sports teams are known as Aggies. The Texas A&M Aggies athletes compete in 18 varsity sports as a member of the Southeastern Conference.



The Meteorology department first began its study of convective storms with the use of a 3 cm wavelength radar in the early 1950s. In 1962, they upgraded to a 10 cm, and in 1966, dual wavelength capability was added. After several modifications, the radar was placed on top of the newly completed Eller O&M Building in 1973. In 1992, the Aggie Doppler RADar was born with the installation of doppler capability. A final upgrade to the pedestal, removal of the side dishes, new processor, and work station occurred in 1997. [1]

Radar object detection system based on radio waves

Radar is a detection system that uses radio waves to determine the range, angle, or velocity of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. A radar system consists of a transmitter producing electromagnetic waves in the radio or microwaves domain, a transmitting antenna, a receiving antenna and a receiver and processor to determine properties of the object(s). Radio waves from the transmitter reflect off the object and return to the receiver, giving information about the object's location and speed.


In the early 1950s, the department received a 3-cm weather radar, AN/CPS-9, from the US Air Force. Using this 3-cm radar, researchers studied mid-latitude mesoscale systems, severe storms, and land-falling cyclones. [2] The AN/CPS-9 model was the first purpose-built weather radar. [3]

The AN/CPS-9 radar, the first radar specifically designed for meteorological use, was produced in the United States around 1949 and unveiled by the Air Weather Service in 1954.

April 5, 1956, tornado warning

"The modified APS-2F at Texas A&M University, although not formally a part of the Texas Tornado Warning Network, was used at least once for warning purposes (Bigler 1956). On 5 April 1956, a tornado that produced damage in Bryan and College Station, Texas, was detected by the Texas A&M University radar. At noon that day, the Weather Bureau Forecast Center at Kansas City, Missouri, had issued what we would today call a tornado watch for an area just to the north of Bryan. The Texas A&M University radar observed strong, tall, hook-shaped echoes with V-notch signatures after 1400 LT. At 1445 LT, Texas A&M University meteorologists called the Bryan Police Department and forecast that a tornado would touch down 30 min. later. Actual damage started at 1509 LT. Texas A&M University also warned the College Station Consolidated School System, which decided to keep the children in their school buildings instead of releasing them at the scheduled time of 1500 LT. This is probably the first warning based solely on interpretation of radar data and is a good example of effective interaction between warning meteorologists and the local community. Today, with improved warning dissemination methods, increased community preparedness, and better radar capabilities and coverage, it would be less likely that a research team would be issuing warnings to communities directly." [4]


In 1962, a longer wavelength radar, 10-cm, was constructed and designated WSR/TAMU-1. The TAMU-1 was updated in 1966 to allow dual wavelength operations. After several modifications, the radar was placed on top of the newly completed Eller O&M Building in 1973. More modifications were made in 1989 in anticipation of adding Doppler capability.

One of the storms that was tracked with this radar was Hurricane Alicia in 1983. [5] As the storm made landfall, the Galveston NWS office lost its radar. [6] The A&M radar tracked the remnants as they moved inland.

The integration of a Lassen Research PSP-32 processor in 1992 enabled Doppler capability. The new system was renamed the TAMU Aggie Doppler Radar (TAMU-ADRAD). This system was updated in 1993. A final upgrade to the pedestal, removal of the side dishes, new processor, and work station occurred in 1997. [2] Starting in October 1998, live radar pictures from the ADRAD were available online during storms. [7]

In 2016, ADRAD data became available for use by the National Weather Service offices and research teams through Gibson Ridge Analyst software (GRLevelX).

Radar properties

The current antenna is a parabolic solid with a 4.88 meter (16 foot) diameter. It is situated 172.5 meters (566 feet) above mean sea level. [8] It rotates at 2.5 RPM (15 degrees per second) or 4.5 RPM maximum (27 degrees per second). Elevation can be set from -1 to 90 degrees.

The transmitter is an Enterprise Electronics DWSR-88S, operating on a wavelength of 10.56 cm (corresponding to 2840 MHz). This frequency is in the S band, which is also used by the NEXRAD network. Peak power is 1 megawatt. [1]

See also

Texas A&M University is also a partner in the Smart-R mobile research radars. See the following for more information -

Related Research Articles

Severe thunderstorm warning

A severe thunderstorm warning is issued by the National Weather Service when trained storm spotters or Doppler weather radar indicate that a thunderstorm is producing or will soon produce dangerously large hail and high winds, capable of causing significant damage. Flooding caused by a thunderstorm's extreme rainfall. A similar warning is issued by Environment Canada's Meteorological Service of Canada from their offices in Vancouver, Edmonton, Toronto, Montreal and Dartmouth. Skywarn issues the severe thunderstorm warnings for the United Kingdom. In Australia, severe thunderstorm warnings are issued by the Bureau of Meteorology.

NEXRAD Fourth-generation weather radars used by the National Weather Service

NEXRAD or Nexrad is a network of 159 high-resolution S-band Doppler weather radars operated by the National Weather Service (NWS), an agency of the National Oceanic and Atmospheric Administration (NOAA) within the United States Department of Commerce, the Federal Aviation Administration (FAA) within the Department of Transportation, and the U.S. Air Force within the Department of Defense. Its technical name is WSR-88D.

WSR-57 Second-generation weather radar used by the U.S. Weather Bureau

WSR-57 radars were the USA's main weather surveillance radar for over 35 years. The National Weather Service operated a network of this model radar across the country, watching for severe weather.

This is a list of meteorology topics. The terms relate to meteorology, the interdisciplinary scientific study of the atmosphere that focuses on weather processes and forecasting.


The National Severe Storms Laboratory (NSSL) is a National Oceanic and Atmospheric Administration (NOAA) weather research laboratory under the Office of Oceanic and Atmospheric Research. It is one of seven NOAA Research Laboratories (RLs).

Canadian weather radar network

The Canadian weather radar network consists of 31 weather radars spanning Canada's most populated regions. Their primary purpose is the early detection of precipitation, its motion and the threat it poses to life and property.

The Center for Analysis and Prediction of Storms (CAPS) was established at the University of Oklahoma in 1989 as one of the first eleven National Science Foundation Science and Technology Centers. Located at the National Weather Center in Norman, Oklahoma, its mission is the development of techniques for the computer-based prediction of high-impact local weather, such as individual spring and winter storms, with the NEXRAD (WSR-88D) Doppler weather radar serving as a key data source.

ARMOR Doppler Weather Radar

ARMOR Doppler weather radar is a C-Band, Dual-Polarimetric Doppler Weather Radar, located at the Huntsville International Airport in Huntsville, Alabama. The radar is a collaborative effort between WHNT-TV and the University of Alabama in Huntsville. Live data for the radar is only available to a limited audience, such as UAH employees and NWS meteorologists. All ARMOR data is archived at the National Space Science and Technology Center located on the UAH campus.

Volumetric Imaging and Processing of Integrated Radar, known by the acronym VIPIR, is an analysis and display program for Doppler weather radar, created and sold by Baron Services. This software allows improved analysis of radar data for private users, in particular television stations, similar to the Weather Decision Support System program used by the National Weather Service.

The AN/APS-2, originally known as ASG, was a surface search radar developed by Philco originally for use in US Coast Guard blimps to detect German submarines. It proved better than several similar models then being built, and was ordered by the RAF Coastal Command where it was known as ASV Mark V. It was used primarily on British Liberator GR bombers, where they were instrumental in closing the Mid-Atlantic Gap and the subsequent destruction of the German U-boat fleet in May/June 1943.

Extreme wind warning

An extreme wind warning is an alert issued by the National Weather Service for areas that are experiencing or could experience 100 knots within an hour due to non-convective, downslope, derecho, or sustained hurricane winds are expected to occur within one hour. EWWs are intended to provide guidance to the general public at a county or sub-county level of winds that could pose a significant threat of casualties. Their issuance is intended to cover as precise of an area as possible and can be issued no prior than two hours before the onset of extreme winds.

VORTEX projects

The Verification of the Origins of Rotation in Tornadoes Experiment or VORTEX are field projects that study tornadoes. VORTEX1 was the first time scientists completely researched the entire evolution of a tornado with an array of instrumentation, enabling a greater understanding of the processes involved with tornadogenesis. A violent tornado near Union City, Oklahoma was documented in its entirety by chasers of the Tornado Intercept Project (TIP) in 1973 and visual observations led to advancement in understanding of tornado structure and life cycles. VORTEX2 utilized enhanced technology allowing scientists to improve forecasting capabilities to improve advanced warnings to residents. VORTEX2 sought to elucidate how tornadoes form, how long they last and why they last that long, and what causes them to dissipate.

Terminal Doppler Weather Radar

Terminal Doppler Weather Radar (TDWR) is a Doppler weather radar system with a three-dimensional "pencil beam" used primarily for the detection of hazardous wind shear conditions, precipitation, and winds aloft on and near major airports situated in climates with great exposure to thunderstorms in the United States. As of 2011, all were in-service with 45 operational radars, some covering multiple airports in major metropolitan locations, across the United States & Puerto Rico. Several similar weather radars have also been sold to other countries such as China. Funded by the United States Federal Aviation Administration (FAA), TDWR technology was developed in the early 1990s at Lincoln Laboratory, part of the Massachusetts Institute of Technology, to assist air traffic controllers by providing real-time wind shear detection and high-resolution precipitation data.

National Weather Service Lincoln, Illinois

National Weather Service Lincoln, Illinois also known as National Weather Service Central Illinois is a weather forecast office responsible for monitoring weather conditions for 35 counties in Central and Southeastern Illinois. The Central Illinois office initially consisted of two forecast offices in Peoria and Springfield until the current location in Lincoln became the sole local forecast office in 1995. Federal meteorology offices and stations in the region date back to the 19th century when the Army Signal Service began taking weather observations using weather equipment at the Springer Building in Springfield. Since that time the presence of the National Weather Service greatly increased with the installation of new weather radars, stations and forecast offices. The current office in Lincoln maintains a WSR-88D (NEXRAD) radar system, and Advanced Weather Interactive Processing System (AWIPS) that greatly improve forecasting in the region. Lincoln is in charge of weather forecasts, warnings and local statements as well as aviation weather.

Leslie R. Lemon is an American meteorologist bridging research and forecasting with expertise in weather radar, particular regarding severe convective storms. Lemon is, along with Charles A. Doswell III, a seminal contributor to the modern conception of the supercell which was first identified by Keith Browning, and he developed the Lemon technique to estimate updraft strength and thunderstorm organization also as a continuation of Browning's work.

The following is a glossary of tornado terms. It includes scientific as well as selected informal terminology.

Multifunction Phased Array Radar

Multifunction Phased Array Radar (MPAR) was an experimental Doppler radar system that utilized phased array technology. MPAR could scan at angles as high as 60 degrees in elevation, and simultaneously track meteorological phenomena, biological flyers, non-cooperative aircraft, and air traffic. From 2003 through 2016, there was one operational MPAR within the mainland United States—a repurposed AN/SPY-1A radar set loaned to NOAA by the U.S. Navy. The MPAR was decommissioned and removed in 2016.

Langley Hill Doppler radar Doppler weather radar on a hill above Washington States Pacific Ocean coastline

The Langley Hill Doppler radar (KLGX) is a National Weather Service NEXRAD Doppler weather radar station on the Pacific coast of Washington State, in the United States. Prior to its construction, Washington's Olympic Peninsula coast was the only portion of the U.S. coastline without weather radar coverage, and there was "virtually no radar coverage is available over the ocean, where the majority of western Washington's weather originates" according to a Weather Service report to the United States Congress. Its location was announced in early 2011, construction started in March, and the unit was commissioned in September, 2011. A major motivation for the station was early detection of Pacific Northwest windstorms; a proponent, Professor Cliff Mass of the University of Washington, said it would provide an additional 6 to 12 hour storm warning to residents of the Pacific Northwest.


  1. 1 2 "TAMU Meteorology Virtual Tour". Archived from the original on 2006-05-02. Retrieved 2006-04-30.
  2. 1 2 "TAMSCAMS' Meteorology Department History". Archived from the original on 2006-01-11. Retrieved 2006-04-30.
  3. NWS timeline Archived 2011-09-27 at the Wayback Machine - see 1954
  4. Roger C. Whiton, et al. "History of Operational Use of Weather Radar by U.S. Weather Services. Part I: The Pre-NEXRAD Era." Weather and Forecasting: Vol. 13, No. 2, pp. 219–243. 19 Feb. 1998. American Meteorological Society. 5 Apr. 2006 <> [ permanent dead link ].
  5. U.S. Army Corps of Engineers - Comprehensive Hurricane Data Preparedness Study website - meteorology page Archived 2011-05-05 at WebCite
  6. U.S. Army Corps of Engineers - Comprehensive Hurricane Data Preparedness Study website - warnings page Archived July 3, 2007, at the Wayback Machine
  7. "'Aggie Radar' Now Available Online." AggieDaily news article.
  8. "TEXACAL radar locations". Archived from the original on 2007-03-10. Retrieved 2006-04-30.