weather test hail mary (2.0)

What are eddies?

Whirls of air formed on the downwind side of an obstacle; size depends on the obstacle and wind speed. Can be small (microscale) or large (mesoscale) and include types like rotors

What are thermal circulations?

Circulations caused by temperature differences where warmer air rises and colder air sinks

What is a sea breeze?

A coastal wind that blows from the ocean toward land during the day as warm land air rises and cool ocean air moves in.

What is a land breeze?

A coastal wind that blows from land to sea at night as land cools faster than the ocean.

What is a mountain breeze?

At night

What is a valley breeze?

During the day

What are katabatic winds?

Strong

What are Chinook winds (Foehn winds)?

Warm

What are Santa Ana winds?

Warm

What are Hadley cells?

Thermally direct cells where warm air rises at the equator and cold air sinks around 30° latitude

What is the single-cell model of atmospheric circulation?

A theoretical model assuming a non-rotating

What is the three-cell model of atmospheric circulation?

A rotating Earth model where circulation divides into three cells per hemisphere—Hadley

What are jet streams?

Narrow bands of strong winds in the upper atmosphere (usually at the tropopause) that move west to east and influence weather patterns.

What are the main types of jet streams?

The subtropical jet stream (20°–30° latitude

What are ocean currents?

Continuous

What is the Gulf Stream?

A warm

What is the California Current?

A cool ocean current flowing southward along the U.S. West Coast.

What is upwelling?

The upward movement of cold

What is El Niño?

A periodic warming of surface waters in the eastern tropical Pacific that disrupts global weather patterns and cuts off nutrient-rich water near South America.

What is La Niña?

A cooling of Pacific surface waters that increases hurricanes and alters global circulation patterns.

What is an air mass?

A large body of air with similar temperature and humidity characteristics throughout.

What is a source region?

The area where an air mass originates and gains its temperature and moisture properties.

What are the classifications of air masses?

Continental (c)

What is a continental polar (cP) air mass?

Cold and dry air that forms over northern Canada and Alaska.

What is a continental arctic (cA) air mass?

Extremely cold and dry air that forms over the Arctic.

What is a maritime polar (mP) air mass?

Cool

What is a maritime tropical (mT) air mass?

Warm

What is a continental tropical (cT) air mass?

Hot

What are lake-effect snows?

Localized snowstorms that occur when cold

What is a front?

The transition zone between two different air masses with contrasting temperatures and densities.

What is a stationary front?

A front with little or no movement; winds blow parallel but in opposite directions.

What is a cold front?

A boundary where cold

What weather is associated with a cold front?

Short

What is a “back door” cold front?

A cold front moving south or southwest along the U.S. Atlantic coast.

What is a warm front?

A boundary where warm

What is overrunning?

When warm air is forced to rise over a cooler air mass ahead of a warm front.

What is an occluded front?

A complex frontal boundary formed when a cold front overtakes a warm front.

What is a cold-type occlusion?

An occlusion where the cold air behind the front is colder than the air ahead.

What is a warm-type occlusion?

An occlusion where the air behind the front is milder than the air ahead.

What is a dryline?

A boundary separating warm

How much can dew point change along a dryline?

Dew point temperatures may drop by up to 10°C (18°F) per kilometer.

What is a polar front?

A global boundary separating warm subtropical air from cold polar air; the birthplace of mid-latitude cyclones.

What is the polar front theory?

A theory describing how cyclones form

What is cyclogenesis?

The development or strengthening of a mid-latitude (extratropical) cyclone.

Where does cyclogenesis often occur?

In the Gulf of Mexico

What is a wave cyclone?

A mid-latitude low-pressure system that forms and travels along a front

What is a frontal wave?

The initial stage of a cyclone where a small disturbance forms along a stationary front.

What is an open wave?

A stage in cyclone development where both warm and cold fronts exist but have not yet occluded.

What is a lee-side low?

A low-pressure system that forms on the downwind (lee) side of mountain ranges.

What is a Nor’easter?

A strong coastal storm along the U.S. East Coast with northeast winds

What is convergence?

The horizontal inflow of air that causes rising motion and low pressure.

What is divergence?

The horizontal outflow of air that promotes sinking motion and high pressure.

What is the role of the jet stream in cyclones?

The polar jet stream provides upper-level divergence

What is a jet streak?

A region of very strong winds within the jet stream that enhances convergence and divergence

What is the World Meteorological Organization (WMO)?

A United Nations agency that coordinates the international exchange of weather data and certifies weather observation procedures.

What is the National Center for Environmental Prediction (NCEP)?

A U.S. government center that collects

What is Doppler radar?

A radar system that measures wind speed and direction by detecting frequency shifts of precipitation particles moving toward or away from the radar.

What does radial velocity measure?

The component of motion directly toward or away from the radar beam.

What is the forecast funnel?

A sequence of steps forecasters use to analyze current and projected conditions

What tools do forecasters use?

Maps and charts

What is AWIPS?

The Advanced Weather Interactive Processing System—a computer system that integrates radar

What is a meteogram?

A time-series graph showing how weather variables (temperature

What information does a meteogram include?

Temperature

What is a sounding?

A vertical profile of temperature

What does a sounding show?

The stability

What is numerical weather prediction (NWP)?

Weather forecasting using computer models that solve mathematical equations describing atmospheric behavior.

What is an analysis in NWP?

A chart that represents the current observed state of the atmosphere.

What is an atmospheric model?

A set of equations that describe the current state of the atmosphere and predict future conditions.

What is data assimilation?

The process of integrating real-time observational data into a numerical model to improve forecasts.

What is a prognostic (prog) chart?

A forecast chart showing expected future conditions

What is resolution in NWP?

The distance between model grid points that determines how detailed the forecast can be.

Why can computer-based forecasts go wrong?

Models may have limited global coverage

What is an ensemble forecast?

A forecasting technique that runs multiple models or simulations with slightly different starting conditions to show uncertainty and confidence.

What is a spaghetti plot?

A chart showing multiple ensemble model runs to visualize forecast variability.

What is a persistence forecast?

A simple forecast assuming current weather conditions will continue.

What is a steady-state (trend) forecast?

A forecast assuming weather systems will move at the same speed and direction as they have been.

What is the analog method?

A forecast based on comparing current weather patterns to similar historical ones.

What is a statistical forecast?

A forecast based on mathematical relationships and past performance of models.

What is a probability forecast?

A forecast that expresses the likelihood of specific weather events based on climatological data.

What is a climatological forecast?

A long-term forecast based on the climate averages of a region rather than current conditions.

What is a weather types prediction?

A forecast method that categorizes atmospheric patterns into groups to help predict similar outcomes.

What is a nowcast?

A forecast that predicts conditions over the next few hours.

What is a short-range forecast?

A forecast covering about 6 hours to a few days.

What is a medium-range forecast?

A forecast extending 3 to 8 days ahead.

What is a long-range forecast?

A forecast covering periods beyond 8 days.

What is a seasonal outlook?

A forecast extending 3 months to a year

How accurate are short-term forecasts?

Forecasts from 12–24 hours are generally very accurate.

What is forecast skill?

The measure of how much more accurate a forecast is compared to persistence or climatology.

How do mid-latitude cyclones typically move?

In the same direction and at the same speed as they have moved during the previous 6 hours.

How do lows and highs move?

Lows move toward the greatest pressure drop

How do meteorologists use 500-mb charts?

To identify troughs

What is a valid forecast sign of approaching rain?

Falling barometric pressure

What is a thunderstorm?

A storm that contains lightning and thunder

What triggers thunderstorms?

Turbulent eddies

What defines a severe thunderstorm?

A thunderstorm producing large hail

What is an ordinary cell (air-mass) thunderstorm?

A thunderstorm produced by local convection in a conditionally unstable air mass with minimal wind shear.

What are the stages of an ordinary cell thunderstorm?

Cumulus stage

What is a multicell thunderstorm?

A group of thunderstorms

What is a gust front?

The leading edge of cold downdraft air from a thunderstorm.

What is a microburst?

A localized downburst less than 4 km in diameter.