Hurricane Erick had strengthened to a Category 4 storm as it approached the coast but weakened to a Category 2 storm before making landfall on Thursday.

Hurricane Erick slammed into Mexico’s Oaxaca state as a dangerous Category 3 storm Thursday morning, unleashing powerful winds at the coast and heavy rains that have caused deadly flooding in the region.

Forecasters expected up to 16 inches of rain could fall across Oaxaca and Guerrero, with lesser totals in Chiapas, Michoacan, Colima and Jalisco states. The rainfall threatened flooding and mudslides, especially in areas with steep terrain.