Here's what I notice when I read a lot of first chapters in a short window: the mistakes stop being invisible.
Starting with weather is almost always announcing that nothing has happened yet. It's the written equivalent of clearing your throat before speaking.
The opening dream sequence belongs in the same category as the character studying themselves in a mirror. Both are the writer's camera facing the wrong direction. The reader didn't show up to watch your protagonist observe themselves. They showed up to be pulled somewhere.
Backstory in chapter one is the writer explaining why you should care, instead of making you care. The explanation is always less convincing than the evidence would've been.
If you can cut the first chapter entirely and start with chapter two, you probably should. Most writers can. The instinct to "set the scene" before anything happens is one of the hardest habits to break because it feels responsible, like stretching before a run.
"She had always been different from the others" is a placeholder sentence, standing in for a first chapter that hasn't been found yet.
Donna Tartt opens The Secret History by telling you who died. That's a deliberate promise, not a spoiler in any conventional sense. The question the novel needs you to ask isn't "who died?" but "how did the narrator come to understand what that meant?" Most first chapters set up the wrong question entirely, and then the writer spends three hundred pages answering a question nobody was asking.
The prologue in genre fiction is often the information the writer couldn't figure out how to embed in the actual story. It sits outside the narrative like a sticky note on the front cover.
A first chapter that ends with the protagonist going to sleep hasn't started.