Mr Spraggs was a regular visitor to Phuket for six years and was well known in Ao Chalong yachting circles.
Police said that during the storm he tried to push a nearby boat away from his yacht and lost his balance, hitting his head on the nearby boat as he fell. He lost consciousness and fell into the water, where he drowned, police said.
“After he fell from the deck, a friend on another boat nearby went to help him and pulled him out of the water, but was unable to revive him,” said Pol Capt Chianchai Duangsuwan, of Chalong police.
Capt Chianchai said that there was a storm in the area at the time and it was raining heavily, a factor he believed might have contributed to Mr Spraggs' accident.
Phuket Cruising Yacht Club club captain Brent McInnes said Mr Spraggs had been involved with the club for a year or so.
"He was a boat owning member of the club. He used to come down the place every day – he was a friendly happy guy. He would talk with most people who came in, and he lived on his boat in the Chalong anchorage."
Mr McInnes described Mr Spraggs as a "cruising yachtie".