Pretty simple.
Its rather silly to see them sitting outside, dancing in the rain or by campfires when its raining.
Simple
Higgins - All inside Higgins by the fire place when Jason bursts through the door and kills Rob Dier...the counselors flee out windows and doors...problem solved
Crystal Lake - The counselors are dancing inside the cabin Alice was in, when Jason bursts through that door and kills someone with a throwing knife...problem solved
Packanack - Have one of the counselors go outside to stretch or have a smoke on the back porch while the counselors inside Packanack are dancing or chilling...Jason throws Rob Dier through the window...problem solved
Jarvis - Counselors are all inside the Jarvis House, then Jason bursts through the window and kills Rob Dier near the window...problem solved.