[al-toh-strey-tuh s, -strat-uh s]
- a cloud of a class characterized by a generally uniform gray sheet or layer, lighter in color than nimbostratus and darker than cirrostratus: of medium altitude, about 8000–20,000 feet (2450–6100 meters).
Origin of altostratus
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for alto-stratus
Alto-stratus is a grey or bluish veil through which the sun and moon are faintly visible, occasionally giving rise to coronæ.Sounding the Ocean of Air
A. Lawrence Rotch
Through openings in these clouds an upper layer of cirro-stratus or alto-stratus may almost invariably be seen.
- a layer cloud at an intermediate height of about 2400 to 6000 metres (8000 to 20 000 feet)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- A mid-altitude cloud that extends in flat, smooth sheets or layers of varying thickness. Altostratus clouds generally form between 2,000 and 6,100 m (6,560 and 20,000 ft) and often produce long, steady rain showers. See illustration at cloud.
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