Strong winds from a South Pacific anticyclone triggered a massive sand and dust storm in southern Peru on Thursday, catching residents in coastal regions by surprise, authorities said.

Peru’s national weather service said wind gusts reached up to 50 kilometers (31 miles) per hour in the Ica region, about 400 kilometers south of Lima.

The effects of the unusual weather event were also felt in the regions of Arequipa, Moquegua, and Tacna – which borders Chile – where winds reached up to 32 kilometers an hour.

The weather agency said the “increase in wind speed, ranging from moderate to strong intensity,” is expected to continue along the Peruvian coast through Sunday.