Scud

From Glossary of Meteorology



scud

Ragged low clouds, usually stratus fractus or cumulus fractus, that occur below the main cloud base.

They are often found in the vicinity of rainshafts. Several mechanisms may explain their occurrence. They may represent rising air that has greater-than-average humidity due to the evaporation of rain or water on the ground. They may evaporate before reaching the main cloud due to mixing with the intervening dry air. Scud may also be attributed to the breakup of raindrops. The breakup fragments that are able to accumulate in regions of high humidity in rainshafts may be the source of some scud.
See pannus.


Copyright 2024 American Meteorological Society (AMS). For permission to reuse any portion of this work, please contact permissions@ametsoc.org. Any use of material in this work that is determined to be “fair use” under Section 107 of the U.S. Copyright Act (17 U.S. Code § 107) or that satisfies the conditions specified in Section 108 of the U.S.Copyright Act (17 USC § 108) does not require AMS’s permission. Republication, systematic reproduction, posting in electronic form, such as on a website or in a searchable database, or other uses of this material, except as exempted by the above statement, require written permission or a license from AMS. Additional details are provided in the AMS Copyright Policy statement.