Air Fronts

Air Fronts

Responsible for changing weather conditions

Weather Fronts

mark the boundary between two air masses. A "front" is the military word used to describe where two armies meet for battle.

Open Ended

Many movies are about war and portray battle scenes. Name a movie you've seen that has an interesting battle scene in it.

A Front: When two opposing air masses (armies) meet

• there can be large temperature differences on either side of the front

• when a front passes there is often a change in wind direction and temperature

Cold front

• Occurs when a colder air mass overtakes a warmer air mass.

• The cold front moves faster than the warm air and pushes it upwards

• Results in heavy rain and violent thunderstorms

• Cold fronts are big bullies!

Open Ended

Describe the most extreme or the most violent weather event you have ever experienced.

The symbol for a cold front is

sharp blue triangles pointing in the direction of air movement

Multiple Choice

A cold front is

• Occurs when a colder air mass overtakes a warmer air mass.

• Warm air steadily rises about cooler air to create gentle rain showers

• Occurs when a cold front catches up and overtakes and captures a warm front

• Boundary between two air masses that are not moving

Warm front

• Move more slowly than cold fronts

• Warm air steadily rises about cooler air to create gentle rain showers

• Warm fronts are passive!

The symbol for a warm front is

rounded red half circles pointing in the direction of air movement

Multiple Choice

An warm front is

• Occurs when a colder air mass overtakes a warmer air mass.

• Warm air steadily rises about cooler air to create gentle rain showers

• Occurs when a cold front catches up and overtakes and captures a warm front

• Boundary between two air masses that are not moving

Occluded front (to close up)

• Occurs when a cold front catches up and overtakes and captures a warm front

• The cold and warm front are at different temperatures as is the "less cold" air mass

• Results in a mix of rain and thunderstorms

The symbol for an occluded front is

rounded purple half circles (warm air) and triangles (cold air)

Multiple Choice

An occluded front is

• Occurs when a colder air mass overtakes a warmer air mass.

• Warm air steadily rises about cooler air to create gentle rain showers

• Occurs when a cold front catches up and overtakes and captures a warm front

• Boundary between two air masses that are not moving

Stationary front

• Boundary between two air masses that are not moving

• Results in clear to partly cloudy skies and occasional light rain.

• A face off! A stare down!

The symbol for a stationary front is

rounded red half circles (warm air) and blue triangles (cold air) on either side of the line

Multiple Choice

A stationary front is

• Occurs when a colder air mass overtakes a warmer air mass.

• Warm air steadily rises about cooler air to create gentle rain showers

• Occurs when a cold front catches up and overtakes and captures a warm front

• Boundary between two air masses that are not moving

Multiple Choice

A cold front is

• Occurs when a colder air mass overtakes a warmer air mass.

• Warm air steadily rises about cooler air to create gentle rain showers

• Occurs when a cold front catches up and overtakes and captures a warm front

• Boundary between two air masses that are not moving

Multiple Choice

An occluded front is

• Occurs when a colder air mass overtakes a warmer air mass.

• Warm air steadily rises about cooler air to create gentle rain showers

• Occurs when a cold front catches up and overtakes and captures a warm front

• Boundary between two air masses that are not moving

Multiple Choice

An warm front is

• Occurs when a colder air mass overtakes a warmer air mass.

• Warm air steadily rises about cooler air to create gentle rain showers

• Occurs when a cold front catches up and overtakes and captures a warm front

• Boundary between two air masses that are not moving

Multiple Choice

A stationary front is

• Occurs when a colder air mass overtakes a warmer air mass.

• Warm air steadily rises about cooler air to create gentle rain showers

• Occurs when a cold front catches up and overtakes and captures a warm front

• Boundary between two air masses that are not moving

Open Ended

Weather data shows that over the past 25 years, the amount of water vapor in the troposphere is increasing. How might global warming be responsible for this? Explain your answer.