Weather Fronts

Created by: Joshua Ortiz

What is a Front?

A front is a boundary separating two air masses of different densities

Cold Front

A fast moving front that is formed when a cold air mass moves under a warm air mass which is less dense and pushes air up. When a cold front is formed it can cause thunderstorms, snow storms, or showers. The clouds that form in this front are cumulonimbus clouds and Anvil cirrus clouds. After the front passes, the weather begins to settle showers continue after the front moves on then a gradual clearing returns.

Warm Front

A warm front is formed when a warm air mass pushes into a cold air mass followed by warmer weather. When a warm front is formed it can cause light rain, showers, or sometimes light snow. The clouds that form in a warm front are altocumulus, altostratus, cirrocumulus, cirrostratus, cirrus, cumulonimbus, nimbostratus, and stratocumulus. After the front passes, it is followed by warmer, milder weather.

Stationary Front

A stationary front is formed when the warm air and the cool air meet in the middle and none of them are strong enough to push each other so they form a standoff. When a stationary front is formed it can cause rain in a place for sometimes many days. The clouds that form in a stationary front are stratiform (stratus, nimbostratus, altostratus, cirrostratus). After the front passes the weather could be either a warm or cold front if the wind direction starts changing so the front will start to move again.

Occluded Front

A occluded front is formed when a warm air mass is between two cooler air masses, the cool air mass moves underneath the warm air mass because it’s denser and the warm air mass pushes it upward. When a occluded front is formed it can cause light rain and strong winds in the area. The clouds that form in a occluded front are a complicated mixture of those associated with warm and cold fronts. After the front passes the weather could be with two types of occlusion, warm and cold: In a cold occlusion, the air mass overtaking the warm front is cooler than the cool air ahead of the warm front, and plows under both air masses. In a warm occlusion, the air mass overtaking the warm front is not as cool as the cold air ahead of the warm front, and rides over the colder air mass while lifting the warm air.
What are weather fronts?