Assertion: cirrostratus | /r/CapableOf | signal the beginning of a warm front
Facets:
value: sometimes
type: TEMPORAL
Source sentences:
text: Cirrostratus clouds sometimes signal the beginning of a warm front if they form after cirrus and spread from one area across the sky and thus may be signs that precipitation might follow in the next 12 to 24 hours  or as soon as 6–8 hours if the front is fast moving.
text: Cirrostratus clouds sometimes signal the beginning of a warm front and thus may be signs that precipitation might follow in the next 12 to 24 hours .