← Cloud Types Export Options Alphabetize Word-Def Delimiter Tab Comma Custom Def-Word Delimiter New Line Semicolon Custom Data Copy and paste the text below. It is read-only. Select All Altocumulus Gray layers of cumulus clouds that cover the sky Altostratus Sheets of gray, dark clouds that bring rain or snow Cirrocumulus Rippling rows of white fleecy clouds Cirrostratus "see-through" white clouds, may be a sign of storms Cirrus Thin, wispy white clouds made of ice crystals Cumulonimbus Dark, towering clouds; Thunderclouds Cumulus Fluffy, white clouds Nimbostratus Thick, low sheet-like clouds that cover the sky Stratocumulus Rounded heaps of white or gray clouds Stratus Grayish-white sheets Fog A low stratus cloud that touches the ground Contrail the cloud of condensation and ice crystals created by an aircraft