AFWAAir Force Weather Agency.
ALBEDOThe percent of radiation returning from a
surface compared to that which strikes it. An
arbitrary value of whiteness possessed by a digital
image or an individual pixel.
ALGORITHMA step-by-step procedure for
solving a mathematical problem.
ANALOGProportional and continuous. Analog
data is collected or presented in continuous form,
such as voltage measurements or temperature
ANOMALOUS PROPAGATION (AP)The
abnormal bending of a radar beam as it passes
through the atmosphere.
ANOMALYDeviation or departure from the
APOGEEThe highest point (greatest distance from
the surface) of a satellite orbit.
APTAutomatic Picture Transmission. The
automatic transmission of images by polar-
ASCENDING NODEThe period of time when a
polar-orbiting satellite is traveling from south
toward the north.
ASSOCIATED PRINCIPAL USERA principal
user linked to a WSR-88D system with a dedicated
ATTENUATIONAny process in which the power
of a beam of energy is dissipated.
AUTODINAutomatic Digital Network.
AWNAutomated Weather Network-the complex
worldwide collection and distribution network of
meteorological data operated by the Air Force.
AZIMUTH The horizontal angular measurement
from a fixed reference to a point. The Navy uses
angular measurements in clockwise degrees from
0 to 360. When 0 is referenced to true north, the
result is a true azimuth bearing. When referenced
to an arbitrary direction, such as the bow of a ship,
the result is a relative azimuth bearing.
BACKINGA change in wind direction in a
counterclockwise manner in the Northern
Hemisphere, or a clockwise direction in the
BACKSCATTER That portion of energy scattered
back from a target to a radar antenna.
BASE DATADigital fields of reflectivity, mean
radial velocity, and spectrum width data provided
at the finest resolution available from the WSR-
88D Doppler radar.
BEAM WIDTHThe angular width of the antenna
pattern. Usually the width where the power
density is one-half that on the axis of the beam.
BOUNDED WEAK ECHO REGION (BWER)A
core of weak equivalent reflectivity in a
thunderstorm that identifies the location of a
BRIGHT BANDThe enhanced layer of a radar echo
caused by the difference in radar reflectivity of ice
and water particles. This echo is interpreted as the
delineation on a radar display between frozen and
CENTROIDThe center of mass of a storm.
CNMOCCommander, Naval Meteorology and
Oceanography Command. Headquartered at
Stennis Space Center, Mississippi.
CONUSConterminous/continental United States.
Those states of the United States enclosed