For those unaware, Los Angeles has several microclimates. The picture of palm trees swaying in the air while women roll around on skates is of Venice Beach, which has a much milder climate than inland areas. Downtown is right in the middle of the Basin, which due to being surrounded by mountains and hills becomes a stew of moisture, smog, and heat. The result is rather unpleasant summer weather from June to September. In fall, several heat waves can bring misery all the way through December, but Halloween is traditionally thought of as either the last hot night or first cold night of the year. If you are able to live near the ocean, especially South Bay, the weather is a lot better and living without A/C is actually viable. If on the other hand, you live in the valley, the north part of LA above the basin, or far to the east closer to the desert, it’s even more hot and frail people can actually die without air conditioning.