ATMOSPHERE
The envelope of air surrounding the planet earth. The atmosphere
extends from the ground to about 180 miles above the planet.
ATMOSPHERIC MODELS
Simulation of the atmosphere's behavior by mathematical
equations or by physical models.
CEILING
The height of the lowest layer of clouds.
CLIMATE
The average of daily and seasonal weather over a long period of
time, often 30 years.
COLD FRONT
The leading edge of a cold air mass advancing into a warm air mass.
DEW POINT
The temperature to which air must be cooled to in order for dew (or
frost) to form.
EL NINO
An extensive warming that begins along the coast of Peru and
Ecuador; occurs once every 3 to 7 years. El Nino refers to "the time
of your (Christmas) which these countries notice changes in
fishing". El Nino means "the little boy" - which refers to the
Christ Child.
FOG
A cloud with its base at the Earth's surface.
FUNNEL CLOUD
Often the initial phase of a tornado, it's a rotating column of air
extending from a cloud but not reaching the ground.
HEAT INDEX
An index that combines the air temperature and relative humidity to
determine an apparent temperature - how it really feels to the human
body.
HIGH
A region of air with higher-than-normal barometric pressure, around
which winds blow clockwise. Usually associated with fair weather.
HEAT LIGHTNING
Ordinary lightning that is too far away for its thunder to be heard;
a misnomer.
HIGH
A region of air with higher barometric pressure than the area
surrounding it, around which winds rotate clockwise; usually
associated with fair weather.
HURRICANE
The largest storm system on the planet, it's the most powerful
tropical system with winds of 74 mph or more.
Saffir-Simpson Damage Scale
|
Category |
Wind Speeds |
Storm Surge |
|
1 |
74-95 mph |
4-5 Feet |
|
2 |
96-110 mph |
6-8 Feet |
|
3 |
111-130 mph |
9-12 Feet
|
|
4 |
131-155 mph |
13-18 Feet |
|
5 |
156+ mph |
More than 18 Feet |
JET STREAM
Strong winds at about 35,000 feet aloft that divide air masses of
different temperatures, and often act as steering currents for
weather systems.
LA NINA
Condition where the central and eastern tropical Pacific Ocean
waters turn cooler than normal. Opposite of El Nino!
LOW
A region of air with lower barometric pressure then the area
surrounding it that rotates counter-clockwise; usually associated
with stormy weather.
METEOROLOGY
The study of the atmosphere and atmospheric phenomena as well as the
atmosphere's interaction with the Earth's surface, oceans and life
in general.
NEXRAD
An acronym for Next Generation Weather RADar, the main component of
NEXRAD is Doppler radar.
PRECIPITATION
Any form of water particles - liquid or solid- that falls from the
atmosphere and reaches the ground.
RELATIVE HUMIDITY
The ratio of the amount of water vapor in the air compared to the
amount of water vapor the air (at a certain temperature) can hold.
SHOWERS
Precipitation which comes and goes at an unsteady rate, could be
rain or snow.
STATIONARY FRONT
A boundary separating two air masses that shows little or no
movement.
TORNADO
The most violent of all storms, it's a strong, rotating column of
air extending from the base of a cumulonimbus cloud to the ground.
TROPICAL DEPRESSION
A tropical cyclone with maximum sustained winds near the surface of
less than 39 mph.
TROPICAL STORM
Tropical cyclone with 39 to 73 mph sustained winds; it's just one
step below hurricane status.
TROPICAL WAVE
A disturbance moving off the western coast of Africa toward the
Caribbean and eastern North American coastal regions which may
eventually develop into a hurricane.
WARM FRONT
The leading edge of a warm air mass advancing onto a cold air mass.
WEATHER
The condition of the atmosphere at any particular time and place.
WIND CHILL
The cooling effect of the combination of temperature and wind,
expressed as the loss of body heat.