Where I live, in December, it’s already night by 4pm, whereas in July, 4pm isn’t even the peak of heat yet. But if someone said “good evening” to me at 4pm in either of them, I’d prob accept it either way, and I’m a meteorologist

Also: In the UK and the US, the typical meteorological standard is just to split seasons by month (DJF MAM JJA SON) for easy stats reasons, but other countries have entirely different standards based on climate. Different people have different definitions and it’s completely fine