MEXICO CITY (AP) — Tropical Storm Beatriz formed off Mexico’s southern Pacific coast Thursday and was forecast to strengthen rapidly to hurricane as early as Friday as it moves closer to the coast.

Beatriz was about 110 miles (180 kilometers) south of Acapulco late Thursday and moving west-northwest at 12 mph (19 kmh) with sustained winds of 40 mph (65 kmh), according to the United States National Hurricane Center.

A hurricane warning was in effect from Zihuatanejo to Playa Perula. The storm was expected to slow its forward movement over the weekend, and dump heavy rain as it scrapes along several southern Mexican states.

Meanwhile, Hurricane Adrian continued to spin away from land into the open Pacific. Late Thursday it was about 450 miles (725 kilometers) south of the southern tip of Baja California, moving west-northwest at 7 mph (11 kmh). It had sustained winds of 85 mph (140 kmh), but posed no threat to land.