A potential catastrophic Hurricane Willa swept towards Mexico's Pacific coast with winds of 250 km/h, threatening a stretch of high-rise resort hotels, surfing beaches and fishing villages.
After briefly reaching Category five strength, the storm's maximum sustained winds weakened slightly to Category four.
But it remained "extremely dangerous" and was expected to bring "life-threatening storm surge, wind and rainfall" to parts of west-central and southwestern Mexico ahead of an expected landfall tomorrow, the US National Hurricane Centre said.
Hotel workers started taping up windows, and officials began evacuating thousands of people and closed schools in a low-lying landscape where towns sit amid farmland tucked between the sea and lagoons.
A decree of "extraordinary emergency" was issued for 19 municipalities in Nayarit and Sinaloa states, the federal Interior Department announced.