"Weather on the 1s" is a slang term that means to be very lucky or fortunate. It's like saying "everything is going your way."

Here's why it's called "weather on the 1s":

* The number 1 is often associated with luck, success, and being on top.

* Weather on the 1s implies that everything is going perfectly, like a smooth and constant flow of luck.

Example:

"I aced my exam, got a promotion at work, and won the lottery last week. I guess I'm weatherin' on the 1s!"

It's important to note that this slang term is informal and might not be understood by everyone.