It’s been exactly one month since the historic schooner Nina was last heard from off the northwestern coast of New Zealand, but a missing text message from that fateful day has reignited hope that the six Americans and one Brit lost at sea may still be alive.

Nina’s seven-team crew included commercial captain David Dyche III, 58; his wife, Rosemary, 60; and their son David IV, 17; their friend Evi Nemeth, 73; Kyle Jackson, 27; Danielle Wright, 18; and Briton Matthew Wootton, 35. The group departed from a marina in Opua, about three hours north of Auckland, on May 29, and has not been seen by any other vessel in the area since June 4, when the U.S.-flagged ship was 425 nautical miles (685 kilometers) northwest of Cape Reinga.

Rescue Coordination Center New Zealand, or RCCNZ, released the last known communication from the 70-foot (21m) vessel Thursday after receiving long-awaited information from satellite phone company Iridium and the U.S. State Department. “Thanks, storm sails shredded last night, now bare poles. Going 4kt 310deg will update course info 6PM (sic),” the undelivered text message read.

Authorities suppose the 84-year-old ship likely sank in high seas that day, but have continued searching in case the seasoned sailors are still alive aboard a life raft. Nigel Clifford, Maritime New Zealand’s general manager for safety and response services, said the team had “grave concerns,” but would not give up hope of finding survivors.

“The text message clearly indicates that the Nina was affected by the storm, but gives no indication of immediate distress,” Clifford said. He added that the contents of the text message were considered, along with all other information, in the decision to continue the search effort.

“While it shows that Nina had survived the storm up to that point, very poor weather continued in the area for many hours and has been followed by other storms. The text message, in isolation, does not indicate what might have happened subsequently. However, the text message states that Nina’s course information would be updated in just over six hours’ time, at 6 p.m.”

The award-winning racing schooner was built in 1928, but was equipped with a satellite phone, a spot device that allows regular tracking signals to be sent manually and an emergency beacon. Yet, Clifford said there had been no further transmissions from Nina since the missing text, nor distress messages from either of the two distress alerting devices on board, perhaps indicating a hasty departure.

RCCNZ began its investigation June 14 following concerns from family and friends after the crew did not complete the 1,100-nautical-mile journey across the Tasman Sea to their intended destination of Newcastle, Australia. The agency’s records show that conditions at the last known position of the vessel on June 4 were quite rough, with winds of 50 mph (80 kmh), gusting to 68 mph, and swells up to 26 feet (8 meters).

The final text message, uncovered Thursday, was likely sent to New Zealand meteorologist Bob McDavitt, who took the last known satellite phone call on June 3 from 73-year-old Nemeth, a revered computer scientist on board the ship. “The weather’s turned nasty, how do we get away from it,” she said. The meteorologist then advised the crew to head south and brace for a storm with strong winds and high seas. He exchanged a series of texts with Evi but the replies stopped coming.

To date, RCCNZ has coordinated seven search missions, coving a combined area of more than 615,000 square nautical miles, making it one of the largest-ever searches of the waters around New Zealand.