FAAFederal Aviation Administration.
Oceanography Center. Located in Monterey,
FULL DISKA satellite image covering an entire
hemisphere produced from a series of smaller area
GEOSTATIONARYA satellite in an equatorial
orbit moving in the same direction as the earth.
The speed and altitude of the satellite is such that it
is always located in a stable orbit over the same
position on the equator.
GHzGigahertz. Equal to one billion hertz (109).
GROUND CLUTTERThe pattern of radar echoes
from fixed ground targets.
GROUND WAVEThat portion of a transmitted
electromagnetic wave that travels in the
atmosphere immediately above the surface of the
GVARGOES Variable data format.
HECTOPASCAL (hPa)A unit of 100 pascals used
to measure pressure, exactly equivalent to 1
HERTZA frequency defined as one cycle per
HFHigh frequency. (1-3 MHz to 30 MHz.)
HOOK ECHOA pendant or hook on the right rear
of an echo that often identifies mesocyclones and
tornadic activity on the radar display.
HRPTHigh Resolution Picture Transmission,
automatically transmitted from polar-orbiting
INCLINATION The angle of the orbital plane of a
satellite relative to the earths equatorial plane.
INFRARED (IR)The portion of the electro-
magnetic spectrum with wavelengths just slightly
longer than visible light (thermal energy).
INVERSIONWith respect to temperature, an
increase in temperature with height. Normally,
temperature decreases with height in the
kHzKilohertz. Equal to one thousand hertz (103).
knAlternate abbreviation for knot. In meteorology,
the more frequently used abbreviation is "kt," but
this should not be confused with the uppercase
"KT" meaning kiloton.
LINE ECHO WAVE PATTERN (LEWP)A radar
echo pattern formed when a segment of a line of
thunderstorms surges forward at an accelerated
LINE-OF-SIGHT An imaginary straight line
between a radar and the target position.
LLWSLow-level wind shear.
LMTLocal Mean Time.
MACROBURSTA large downburst with 4 km (2
nmi) or larger outflow size with damaging wind
lasting 5 to 20 minutes.
thunderstorm that rotates (usually cyclonically)
and is correlated with severe weather.
METEOROLOGY The study of phenomenon of
METVANSUSMC mobile meteorological vans.
Highly transportable, completely equipped
meteorological facilities constructed as complete
modules in cargo containers.
MFMedium frequency. (300 kHz to 3 MHz.)
MHzMegahertz. Equal to one million hertz (106).
MICROBURSTA small downburst, 1 to 5 km (0.5
to 2.5 nmi) in outflow size, with peak winds lasting
2 to 15 minutes.
MICROMETER A unit of length equal to one
millionth (10-6) of a meter. Also called a micron.