Precipitation occurs when moist air rises to cooler altitudes, condensing the water out of the air into droplets. Once these droplets become heavy enough, often by coalescing around motes of dust or other particles, they fall out of the cloud as precipitation. Without significant updrafts bringing more moisture to the cloud layer, the condensed water may remain light enough to stay aloft, which is why not every cloud brings rain.Know More
Rain clouds may form in a variety of meteorological conditions. Commonly, they occur across frontal boundaries, where a mass of warm air is forced upward by a cold front, pushing a large amount of moisture into the upper atmosphere. This is the cause of long, soaking rains due to the sheer amount of condensation produced by the updrafts. Air masses may also be pushed upward by topographic features like mountains, producing rain on the lee side of these geologic features.
Another type of rain is produced when the sun's heating creates a convective current in the atmosphere. This energy heats the air near the ground, causing it and its moisture to rise in a relatively small area. This pattern tends to create small, isolated showers that can be extremely vigorous but may not move quickly, a common weather pattern in the summer months.Learn more in Clouds
Most commonly, rain clouds that produce a steady rain are referred to as nimbostratus clouds. These clouds appear low in the sky and are a medium to dark gray color. Sometimes stratus clouds are associated with a light drizzle.Full Answer >
Cumulonimbus clouds, also known as thunderheads, release hail and rain in conjunction with updrafts. Ice crystals ride such updrafts into the air and then fall through the clouds, collecting water droplets as they drop. Once water droplets freeze onto ice crystals, hailstones are created. Cumulonimbus clouds release rain when they have reached their moisture saturation point.Full Answer >
Dark rain clouds are called stratus clouds. They are rainy, dense, dark or snowy clouds that sometimes appear as white cottony clumps surrounded by blue sky.Full Answer >
Clouds are formed when moist, warm air rises and expands in the atmosphere. The rising water vapor condenses and forms small water droplets which make up the clouds. When the water vapor cools, the low temperature of air lowers its capacity to hold water vapor.Full Answer >