Nimbo is from the Latin word "nimbus" meaning rain. A Nimbostratus is a
cloud of the class characterized by a formless layer that is almost uniformly dark gray; it is a rain cloud of the layer type, of low altitude, usually below 8000 ft (2400 m) and sometimes down to 350 ft (100 m). Nimbostratus block a great amount of
sunlight as a result of its characteristic dense structure. Thickness of nimbostratus layer is usually 6500..10000 ft (2000..3000 meters), but can reach up to 15000 ft (4500 m) and down to 3500 ft (1000 m). Nimbostratus in rare cases can be very thin and accompanied by separate layer of
altostratus divided by cloudless layer.
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