It's possible to save a few more seconds if executed more perfectly, but I'm tired of doing all this again.

This strat requires Freezing Wave on Day 2. Preparations:

Items that should be in the inventory at the end of Day 2:

• Extension Cord (saves a few seconds unplugging the AC and going to another room. This immediately forces Day 2 to be Freezing Wave since Heat Wave cannot be survived without electricity)
• Shovel
• Full Fuel Caninster
• Bandage
• Duct Tape

Map preparations before the day:

• The car and the bridge should be repaired
• The car should be fueled and parked at the restaurant (any better place?)
• All places accessed for fast traveling
• The front door or the window in the living room should be left open (saves a few seconds opening them)
• The hatch in the roof should be left open (saves <1 second opening the hatch. A short but stable time save)