weather & climate

Dry adiabatic lapse rate

The rate at which an unsaturated air parcel cools as it ascends, approximately 5.5º F per 1000 feet.

Wet adiabatic lapse rate

The rate at which a saturated air parcel cools as it ascends, approximately 3.2º F per 1000 feet.

Rainshadow effect

A phenomenon in which an area on the leeward side of a mountain experiences significantly less precipitation due to descending, warming air.

Isobar

A line connecting points of equal air pressure.

Atmospheric pressure at sea level

Standard value of approximately 1013.25 millibars.

Coriolis force

A force caused by Earth's rotation that affects the direction of winds and ocean currents.

Horse Latitudes

Regions located at approximately 30 degrees latitude characterized by low wind and stable weather.

Air pressure gradient

The difference in air pressure between two areas that causes wind to flow from high to low pressure.

Coriolis effect

The deflection of moving objects, including air, due to Earth's rotation.

Katabatic winds

Cold winds that flow down from elevated terrains downhill, often occurring at night.

Chinook winds

Warm, dry winds that descend the leeward side of mountains, often causing rapid warming.

Broadcast Meteorology

The field of meteorology focused on presenting weather information to the public through various media.

Undergraduate Degree

A degree in Meteorology or a related Atmospheric Science field required for becoming a broadcast meteorologist.

Summer Internship

Hands-on experience at a TV station that helps aspiring meteorologists gain contacts in the field.

Mega Doppler Radar

The most powerful radar in SE Texas, used to detect precipitation intensity and particle velocities.

Chroma Key

A technique that uses a green screen to allow meteorologists to display weather data behind them during broadcasts.

AccuWeather Planner

A forecast tool that provides viewers with detailed weather forecasts for different times of the day.

Networking Sites

Platforms like Facebook and Twitter that broadcast meteorologists maintain for audience engagement.

Severe Weather Desk

A dedicated workstation for monitoring dangerous weather conditions using advanced radar technology.

Eyewitness Weather

The branding used by ABC-13 Houston for its weather forecasting segment.

Tim Heller

The Chief Meteorologist at ABC-13 Houston, known for his work in broadcast meteorology.

Hadley Cells

Atmospheric circulation cells that exist between the equator and about 30° latitude, driving trade winds.

ITCZ (Inter-Tropical Convergence Zone)

A region near the equator where the northeast and southeast trade winds converge, characterized by low pressure and rain.

Subtropical High Pressure Belt

A belt of high pressure located around 30° latitude characterized by dry air and desert conditions.

Doldrums

A region near the equator where winds are light and variable, often leading to calm conditions.

Westerlies

Wind systems that blow from the west in the mid-latitudes (30°-60°), causing varied weather conditions.

Polar High Pressure Belt

A region of high pressure at the poles characterized by very cold, dry air.

Trade Winds

Steady winds that blow from east to west between the equator and the subtropics.

Equatorial Low Pressure Belt

The area around the equator with rising air, warm temperatures, and moist conditions.

Monsoon

Seasonal prevailing wind patterns that cause wet and dry periods, especially in South Asia.

Polar Front

The transition zone between cold polar air and warmer air from the mid-latitudes, often associated with storm development.

Subpolar Low Pressure Belt

A belt of low pressure around 60° latitude where warm, moist air meets cold polar air.

Atmospheric Pressure

The force exerted against a surface by the atmosphere, caused by the weight of air.

Barometer

An instrument used to measure atmospheric pressure.

Typhoon Tip

The strongest hurricane on record, reaching a minimum pressure of 870 millibars.

Pressure Gradient Force

The force that causes air to move from areas of high pressure to areas of low pressure.

Centripetal Force

A center-seeking force that directs wind in a curved path.

Coriolis Effect

The deflection of moving air caused by the rotation of the Earth.

Hadley Cells

Large scale patterns of atmospheric circulation that lead to trade winds and affect climate.

Global Winds

Winds that are affected by the uneven distribution of solar energy across the Earth's surface.

Variations in Pressure

Changes in air pressure that can occur both vertically and horizontally.

Siberian Winter of 1968

Event noted for the highest recorded atmospheric pressure of 1084 millibars.

Upper-Level Winds

Winds that occur at high elevations in the troposphere with high wind velocities, where friction is not a factor.

Geostrophic Winds

Winds that blow parallel to the isobars and do not form closed circles, typically found at higher altitudes.

Gradient Winds

Upper-level winds that flow in circles around closed circular isobars, associated with low and high-pressure systems.

Subtropical Jet Stream

High-speed winds that flow above the Subtropical High Pressure areas, influencing severe weather in the southern US.

Latitudinal Winds

Upper-level winds flowing parallel to lines of latitude, exhibiting a North-South temperature gradient with little East-West change.

Meridional Winds

Upper-level winds with developed ridges and troughs, creating both North-South and East-West temperature changes.

El Niño Southern Oscillation (ENSO)

An ocean-atmosphere phenomenon occurring every 3-7 years, caused by changes in ocean, wind, and pressure systems in the eastern Pacific.

Cyclonic Winds

Winds that flow counter-clockwise in the Northern Hemisphere around areas of low pressure.

Anticyclonic Winds

Winds that flow clockwise in the Northern Hemisphere around areas of high pressure.

Polar Jet Stream

A high-velocity wind stream located within the Upper-Level Westerlies that impacts weather by converging cold polar and warmer mid-latitude air.

Atmospheric Pressure

The force exerted against a surface by the atmosphere, resulting from the weight of air above.

Pressure at Sea Level

1013.2 millibars, the standard atmospheric pressure measurement.

Typhoon

A hurricane occurring in the Eastern Hemisphere.

Barometer

An instrument that measures atmospheric pressure.

Highest Pressure on Record

1084 millibars, recorded during the Siberian Winter of 1968.

Pressure Gradient Force

The amount of pressure change over a given distance, which drives wind.

Centripetal Force

A center-seeking force that directs wind in a curved path.

Coriolis Effect

The deflection of air due to Earth's rotation, causing winds to shift to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.

Hadley Cells

Convection cells established by warming air at the equator which rises and spreads as it moves toward the poles.

Global Wind Circulation

The large-scale movement of air that distributes thermal energy across the planet.

Continental-Scale Winds

Horizontal and vertical movement of air across large areas.

Pressure Gradient Force

The force that drives air from areas of high pressure to areas of low pressure.

Coriolis Effect

The apparent deflection of moving air or water caused by the rotation of the Earth.

Cyclone

A low-pressure system characterized by air converging counter-clockwise and rising vertically.

Anticyclone

A high-pressure system where air diverges clockwise and descends, generally associated with fair weather.

Convergence

The process where winds come together leading to rising air.

Orographic Lifting

The lifting of air over mountains causing cooling and condensation.

Frontal Wedging

When warm and cold air masses meet, causing the warm air to rise.

Convective Lifting

Lifting of air due to differential heating of the Earth's surface, causing varying temperatures.

Rain Shadow Effect

A region that receives significantly less precipitation due to being located on the leeward side of a mountain range.

Sea Breeze

A wind that blows from the sea to the land, caused by the differential heating of land and water.

Land Breeze

A wind that blows from the land to the sea, occurring at night when land cools faster than water.

Valley Breeze

A breeze that originates in the valley and flows upwards during the day.

Katabatic Wind

Cold, dense air flowing down a slope due to gravity.

Chinook Wind

A warm dry wind that descends the eastern slopes of the Rockies.

ITCZ (Inter-Tropical Convergence Zone)

A band of clouds that represents a continual low pressure zone with year-round precipitation.

Hadley Cells

Large-scale atmospheric circulation cells that are formed by rising air at the equator and sinking air around 30° latitude.

Subtropical High Pressure Belt

A pressure belt located at 30° N/S characterized by dry air and descending air, leading to deserts.

Trade Winds

Steady winds that flow from the subtropical high pressure belts towards the equator, influenced by the Coriolis effect.

Westerlies

Winds that blow from the west between 30° and 60° latitude in both hemispheres.

Polar Front

The boundary between cold polar air and warm air from the south, creating low pressure as warm air rises.

Doldrums

A region around the equator characterized by weak, variable winds and the convergence of the trade winds.

Polar Easterlies

Cold, dry winds that blow from the east between 60° and 90° at both poles.

Subpolar Low Pressure Belt

Located between 55° and 70° N/S, created by the collision of Subtropical Highs and Polar Highs.

Monsoon

Seasonal winds that bring heavy rainfall, significantly impacting agriculture and the climate in regions like South Asia.

Cloud

Visible aggregates of minute droplets of water or tiny ice crystals suspended in the atmosphere.

Nephology

Branch of meteorology that studies clouds.

Condensation nuclei

Dust, smoke, ash, or salt particles that water vapor condenses around to form clouds.

Orographic lifting

Uplift of air caused by mountains.

Frontal wedging

Uplifting of air that occurs when a cold front meets a warm front.

Convergence

When winds from different directions meet and force air upward.

Convective lifting

Uplifting of warm air due to heating at the surface.

Cirrus

High, white, thin clouds that appear as extended wispy fibers.

Stratus

Layered clouds that cover most of the sky with no distinct breaks.

Cumulus

Puffy clouds that resemble cauliflower.

Cirrocumulus

Puffy, high elevation clouds indicating fair weather.

Nimbostratus

Uniform dark gray clouds that completely block sunlight and indicate precipitation.

Cumulonimbus

Towering cumulus clouds with anvil heads that indicate severe weather.