Large and powerful waves have been causing beach erosion and coastal inundation in parts of eastern NSW today, with waves washing onto properties at the storm-weary Collaroy Beach.

A large and powerful easterly swell has been hammering central NSW beaches on Thursday morning. This swell was produced by a very long fetch of powerful easterly winds blowing across the Tasman Sea in recent days.

Image: Modelled wind speed and direction on Wednesday, March 2, showing a long fetch of strong to gale force easterly winds stretching around 3,000km over the Tasman Sea.

These winds whipped up a powerful long-period swell that has prompted a severe weather warning for damaging surf and abnormally high tides, and a hazardous surf warning, in eastern NSW.

A waverider buoy located about 10 km to the east of Sydney’s Curl Curl Beach registered a maximum wave height of 8.8 metres at 9am AEDT on Thursday. At around the same time, the peak wave period was hitting 15 seconds, showing that this easterly swell was powerful. The swell was also coming almost directly from the east, which is a direction that is known to exacerbate erosion at NSW beaches.

The photos below capture the impact of this this large and powerful swell on Sydney’s Northern Beaches during Thursday morning’s high tide.

Image: Collaroy-Narrabeen, NSW on Thursday. Credit: Felix Levesque

Thursday’s waves were lapping at the recently installed sea wall at Collaroy, which was installed to protect properties following damage from another East Coast Low in June 2016. However, other properties further down the beach had waves washing over their yards on Thursday morning.

Image: Thursday's swell lapped against Collaroy's sea wall. Credit: Felix Levesque

Wind and waves should ease gradually over the coming days, however a hazardous surf warning has already been issued for the entire NSW coast on Friday.