MEXICO CITY (AP) — Hurricane Darby has strengthened into a Category 4 storm while far out in the Pacific west of southern Mexico, with forecasters saying it poses no threat to land.

Darby became a hurricane Sunday, and the U.S. National Hurricane Center says its maximum sustained winds had reached 140 mph by Monday afternoon. It was centered about 1,135 miles west-southwest of the southern tip of Mexico’s Baja California peninsula.

Darby is forecast to strengthen some more but then begin weakening by midweek and be a tropical depression by Saturday while approaching an area to the south of the Hawaiian Islands.