The teenage boy went missing on Sunday afternoon. (Supplied)

In short: 

The search for a 16-year-old boy who was swept from rocks near Granite Island has resumed this morning.

Emergency crews were called to the area on Sunday afternoon, but were unable to find the teen.

Police say the search effort this morning is being hampered by dangerous weather conditions in the area.

A search and rescue operation for a teenage boy who was swept off the coast of Victor Harbor, a popular tourist town in South Australia, has resumed.

Emergency crews including South Australian Police, PolAir and the local sea rescue squadron attended an area close to Granite Island on Sunday afternoon after reports a boy was swept from rocks.

SA Police say the alarm was raised about 3:15pm on Sunday after the 16-year-old from Blair Athol, in Adelaide’s north, was seen to fall into the water.

“Unfortunately he wasn’t located, with search crews encountering some really rough conditions down there,” Senior Constable David Bacchus told ABC Radio Adelaide on Monday morning.

Police say Surf Lifesaving SA vessels are on stand-by this morning. (ABC News: Caroline Horn)

The search has now resumed in what will continue to be challenging conditions for crews, with a severe weather warning for damaging winds in place.

Senior Constable Bacchus said it would be a “tough day ahead” for volunteers and crews given the weather conditions.

SA Police said PolAir was searching waters near Granite Island on Monday morning, while officers and volunteers from the State Emergency Service were conducting foot searches of the area.

According to the Metropolitan Fire Service, the boy had been swept out and other swimmers tried to assist, but had to abandon their efforts.

Police are leading the search and rescue operation. (Supplied)

Witness Akash, who was at the scene, said he saw a mother crying and shouting.

“No one had any idea what was happening — but something is not right,” Akash said.

“We are praying.”