Answer: clouds

AnswerCrossword Clue
CLOUDS

Mare's-tails.

CLOUDS

Cumulus and cirrus

CLOUDS

They may rain on your parade

CLOUDS
Water droplets aloft
CLOUDS
They rain on your parade
CLOUDSSymbols of impending trouble
CLOUDSThey keep people off beaches
CLOUDSObscures
CLOUDSSilver-lining items
CLOUDSCumuli.
CLOUDSPlanes may bisect them
CLOUDSCirrus, nimbus, cumulus, etc.
CLOUDSRain makers.
CLOUDSClear sky's lack
CLOUDSSky sights
CLOUDSSun blockers
CLOUDSStorm warnings
CLOUDSRain omens
CLOUDS"Ice cream castles in the air," in a Mitchell song