Weather vs Whether
Quick answer: Weather is what the sky is doing — rain, sun, snow. Whether introduces a choice or possibility (whether or not). If you could swap in 'if', you want whether.
Weather
Noun: the state of the atmosphere — rain, sunshine, wind, temperature.
“The weather turned cold overnight.”
Whether
Conjunction: introducing alternatives or a possibility.
“I don't know whether she's coming.”
How to remember it
The sEA affects the wEAther — both have EA.
Common mistake
'Wether or not' — that spelling is actually a neutered ram; you want whether.