Cold air is more dense than warm air, so when a warm air mass meets a cold air mass, the cold air ends up below the warm air. Once the air has risen, it cools and clouds can form.
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Cloud Formation Due to Weather Fronts
Weather fronts can cause clouds to form. Fronts occur when two large masses of air collide at the Earth's surface.
Warm fronts produce clouds when warm air replaces cold air by sliding above it. Many different cloud types can be created in this way: altocumulus, altostratus, cirrocumulus, cirrostratus, cirrus, cumulonimbus (and associated mammatus clouds), nimbostratus, stratus, and stratocumulus.
Cold fronts occur when heavy cold air displaces lighter warm air, pushing it upward. Cumulus clouds are the most common cloud types that are produced by cold fronts. They often grow into cumulonimbus clouds, which produce thunderstorms. Cold fronts can also produce nimbostratus, stratocumulus, and stratus clouds.
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When a front passes over an area, it means a change in the weather. Many fronts cause weather events such as rain, thunderstorms, gusty winds, and tornadoes. As a cold front passes there may there may
...more Altocumulus clouds (weather symbol - Ac), are made primarily of liquid water and have a thickness of 1 km. They are part of the Middle Cloud group (2000-7000m up). They are grayish-white with one part
...more Altostratus clouds (weather symbol - As) consist of water and some ice crystals. They belong to the Middle Cloud group (2000-7000m up). An altostratus cloud usually covers the whole sky and has a gray
...more Cirrocumulus clouds (weather symbol - Cc) are composed primarily of ice crystals and belong to the High Cloud group (5000-13000m). They are small rounded puffs that usually appear in long rows. Cirrocumulus
...more Cirrostratus (weather symbol - Cs) clouds consist almost entirely of ice crystals and belong to the High Cloud (5000-13000m) group. They are sheetlike thin clouds that usually cover the entire sky. The
...more Cirrus (weather symbol - Ci) clouds are the most common of the High Cloud (5000-13000m) group. They are composed entirely of ice and consist of long, thin, wispy streamers. They are commonly known as
...more Cumulonimbus (weather symbol - Cb) clouds belong to the Clouds with Vertical Growth group. They are generally known as thunderstorm clouds. A cumulonimbus cloud can grow to such heights that it actually
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