The Hawaiian Islands are at risk of significant impacts from PTC 1-C, particularly due to heavy rainfall and potential flooding. Rainfall totals of 5-10 inches, with isolated areas receiving up to 20 inches, could lead to life-threatening flash floods and mudslides, especially in mountainous regions. Gusty winds may also cause localized damage, including downed trees and power lines. The exact locations of the heaviest rainfall remain uncertain, and residents and visitors are urged to stay informed as the system approaches.