The sister of missing British yachtsman Steve Warren said her family was "shocked" that the US Coast Guard called off the search "so quickly".
Kay Coombes told ITV News: "I understand the weather conditions were very poor ... but they might have missed something because the weather conditions were so bad.
"What we're asking is 'Keep searching. The weather conditions may be improving - please keep searching'."
With no sign of a life raft or of debris, and with nearly 20,000 square miles having been searched, the hunt continues for another day.
Veteran yachtsman Tony Bullimore tells ITV News that there is a "strong possibility" the yachtsmen are still alive in the life raft.