Three Orange County beaches–Bolsa Chica, Surfside and Sunset–have been closed as of Thursday evening due to shark sightings.

KTLA reports that a surfer at Sunset Beach encountered a particularly aggressive juvenile great white shark, though no contact was made.

The shark sightings occur just ahead of a busy weekend at the coast, as residents seek relief from a heat wave. The National Weather Service is also warning of strong rip currents through Sunday evening.