Clouds are simply pockets of moisture in the air. If the moisture becomes saturated it will turn into liquid and fall to the ground as rain, snow, sleet, or hail, depending on air temperature. The point at which moisture turns into a liquid is called the dew point.
Clouds are named for their shape. Stratus (layered) clouds are flat. Cumulus (accumulated) clouds are chubby. If the clouds are raining, the term “nimbus” is added: “nimbostratus” or “cumulonimbus.” High clouds are identified by the prefix “alto,” as in altostratus. Broken clouds are called “fracto,” as in fractocumulus.
So let’s discuss cloud cover, also known as sky condition. Clear (abbreviated SKC) means there are no clouds in the sky (except maybe a tiny wisp of a cloud on the horizon). Scattered (SCT) means that 1/8 to 1/2 of the sky has cloud coverage. Broken (BKN) means that 5/8 to 7/8 of the sky is covered with clouds; also known as “mostly cloudy.” Overcast (OVC) means what it says: the entire sky is covered with clouds (except maybe a tiny blue spot on the horizon). These terms are important because VFR pilots must abide by ceiling limits. A ceiling is the lowest broken (more than 5/8 coverage) or greater layer of clouds.
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You’ll learn more — much more — about clouds and weather in ground school. For now, just remember that you are a student pilot, meaning that you’re supposed to stay away from clouds.
"Man cannot discover new oceans unless he has the courage to lose sight of the shore."
-- Andre Gide