The Bureau of Meteorology has now cancelled a severe thunderstorm warning for the Illawarra.
While the immediate threat has passed, the BOM will continue to monitor the situation and issue further warnings if necessary.
A regional warning for severe thunderstorms is still in effect for large hailstones and heavy rainfall in the Newcastle, Gosford, Sydney, Penrith, Parramatta and Katoomba areas.
A general storm warning remains in effect for the Illawarra, however the region is not expected to experience severe weather conditions.
For emergency help in floods and storms call the SES on 132 500.