The SES received about 30 calls for help between Saturday evening and Sunday afternoon.

Calls were mainly about fallen trees in Wollongong and Shellharbour.

Westerly winds reached up to 60km/h on Sunday, causing problems for the annual Wings over Illawarra air show and creating chilly conditions for the region's first Color Run.

Winds are expected to drop to 20km/h on Monday but swells are expected.

The Roads and Maritime Service has issued an alert about dangerous surf, warning skippers to be on high alert.

Rock fishers should also check weather forecasts to decide if it is safe to fish.