New warnings after Melb-Tas ferry crash

The Spirit of Tasmania's crew could have had up to 15 minutes to stop the ferry running aground at a Melbourne beach if severe weather warnings were better communicated.

Instead they had just a few minutes to try to keep the ship from hitting the beach during a sudden storm in January 2016.

Australia's national transport safety investigator says while the squall left little time for the crew to respond, the bad weather had been predicted 15 minutes before the ferry broke its moorings at Port of Melbourne.

Some crew and 120 passengers were on board and vehicles were still boarding when the wind speed of 50km/h accelerated to 110km/h within minutes.

The sudden change increased the wind loading on the ship six-fold.

"With the strong winds pushing the stern away from the wharf, the ship's aft mooring lines failed in rapid succession," the Australian Transport Safety Bureau report, released on Thursday, said.

As all but two of its 10 moorings broke, the Spirit of Tasmania II swung towards the shore and ended up perpendicular to the Station Pier about 6pm on January 13, 2016.

Passengers were served food and drink before the ship was brought back alongside the pier at 7.05pm.

The bureau noted the crew's swift response to the emergency, but said the ship's operator, TT-Line, used adverse weather procedures that didn't take into account all the necessary factors to defend against significant, short-term weather events.

It also found the port authority had been contacting a number of port users and warning about severe weather since 5.25pm, but didn't notify the Spirit.

The report says the port authority has improved the way it communicates official weather warnings and urged all masters of ships to listen in at all times.

TT-Line has changed the way it moors its ships and how it monitors weather, including having an alarm sound if winds exceed 65km/h.