Wow. We are on the same sheet today. I was going to ask almost the exact same question.

First, the boss would either do a transfer of power in a way that does not diminish his standing but expresses his belief the best chance for survival is for that person to be giving orders. Or you tell him you will give him he can be the leader your his trusted adviser and does what you say. It sound draconian but a team needs only one leader.
Next, make sure everyone stays in one area to increase room temperature.
Next, have a group insulate the room to create more heat.
Next, have someone take a head count with everyone's name and number.
Next, have a group bring all the food, water, blankets (etc) they can to the room.
Next, have a group catalog our assets for use and prepare a rationing system for food and water.
Next, find a way to receive communications and transmit our situation (a car radio, a cell phone, laptop wifi).
Next, have a group locate playing cards, iPods, board games, books, magazines for people to stay busy.
Next, observe for those that are engaged and those that are losing it. Manage the minds of the people. Find out what strengths you have in the people around you.
Next, after getting feedback from all the above have a meeting with everyone and lay out what the plan will be for the next several hours or days to keep people warm, fed, hydrated, happy, hopeful.