I volunteered for 9 hours three years ago for The Rim Fire, near Yosemite. It was at the Sonora Fair Grounds, and the Red Cross had set up. I started in the old folks room, setting up privacy screens and making beds for the elderly. It was horrible to see very old people in various medical shape come into the room with their clothes on their back, clutching purses and each other. Volunteer nurses and two Dr's were there.
In another of the Fair grounds halls, were the families. Mothers, fathers, kids and teenagers who were so horrified to be seen there. I helped set up cots - about 400 of them. Food banks from all over came with highly organized routines of feeding the evacuees. Certainly many of these groups had drilled and planned and were under the direction of the Red Cross man in charge.
Another room was for people with pets. Humane society came with crates for the displaced pets. Pets had to stay outside so you can imagine all the dogs and cats under canopies. (100 degrees most days) One lady had her two parakeets - they were the re- incarnation of her two children who had died years earlier. The RC didn't allow her parakeets to be in this hall, so the first night she slept outside with them. Mental health came in and found her and the birds a temp home at a volunteer's house.
As the fire ebbed and flowed and moved, people drifted away from the Fair grounds. It was finally shut down about 2.5 - 3 weeks after the beginning of the Rim Fire.
What an operation that was! I was impressed at the skills and organization of it all.