Wind and rain caused the thunderstorm to dump sand and dust it had picked while passing over the coastal town of Onslow on its way out to the Indian Ocean, Bureau of Meteorology forecaster Austen Watkins said. (Perth Weather Live / Brett Martin)
Meteorologists call the freaky phenomenon a "haboob." (Perth Weather Live / Brett Martin)
A tugboat worker who captured some shots of the event said visibility was reduced to a few hundred feet and swells rose about six feet. (Perth Weather Live / Levi Cooper)
"It was like a big dust storm under a thunderhead, there was a lot of lightning but not a lot of rain," Martin told the West Australian. (Perth Weather Live / Alicia Gomersall)