Meteorology Part 2

air mass

A large volume of air that has nearly the same temperature and humidity at different locations at the same altitude.

air pressure

The force of air molecules pushing on an area.

dew point

The temperature at which air with a given amount of water vapor will reach saturation.

front

The boundary between air masses.

high-pressure system

A generally calm and clear weather system that occurs when air sinks down in a high-pressure center and spreads out toward areas of lower pressure as it nears the ground.

humidity

The amount of water vapor in air.

hurricane

A tropical low-pressure system with sustained winds of 120 kilometers per hour (74 mi/h) or more.

isobar

A line on a weather map connecting places that have the same air pressure.

lightning

A discharge of electricity from one part of a cloud to another or between a cloud and the ground, causing a bright flash of light.

low-pressure system

A large and often stormy weather system that occurs when air moves around and into a low-pressure center, then moves up to higher altitudes.

ocean current

A mass of moving ocean water.

storm surge

A rapid rise in water level in a coastal area that occurs when a hurricane pushes a huge mass of ocean water, often leading to flooding and widespread destruction.

thunder

The sound wave created by intensely heated air around a lightning bolt.

thunderstorm

A storm with lightning and thunder.

tornado

A violently rotating column of air stretching from a cloud to the ground.

tropical storm

A low-pressure system that starts in the tropics with winds of at least 65 kilometers per hour (40 mi/h) but less than 120 kilometers per hour (74 mi/h).

tsunami

A water wave caused by an earthquake, volcanic eruption, or landslide.

cold front

Cold air mass overtakes a warm air mass.

continental air mass

Air masses that build over land.

isotherm

A line on a weather map connecting places that have the same temperature.

maritime air mass

Air masses assembled over oceans.

occluded front

When two cold air masses collide and push a warm air mass up between them.

stationary front

When air masses tend to remain in place for a period of time.

warm front

Warm air mass overtakes a cold air mass.

weather box

An organized collection of symbols used to represent weather d