Why Did Hurricane Nolo Become Typhoon Nolo Overnight?

Nolo did not become a different kind of storm; crossing the International Date Line moved it into the basin where the same phenomenon is called a typhoon.

It was the same storm in a different naming zone. When a tropical cyclone crosses the International Date Line from the central Pacific into the western Pacific, forecasters switch from “hurricane” to “typhoon” because each ocean basin uses its own term. The Atlantic and eastern Pacific use hurricane, the western Pacific uses typhoon, and the Indian Ocean generally uses cyclone.

Nothing about that label change made Nolo stronger; in fact, its sustained winds eased from 115 mph to 100 mph as it crossed, and it remained over open ocean far from land. The useful habit is to treat the name as a location clue, not a danger rating. To judge risk, check the category, sustained wind speed, forecast cone, storm-surge outlook, and official local alerts.