I thought it was the sailors?
You are obviously more familiar with mariners........... applicable to both according to the Met Office..
Red sky at night
The concept of "Red sky at night, shepherd's delight. Red sky in the morning, shepherd's warning" first appears in the Bible in the book of Matthew. It is an old weather saying often used at sunrise and sunset to signify the changing sky and was originally known to help the shepherds prepare for the next day's weather.
Despite there being global variations in this saying such as "Red sky at night, sailors delight. Red sky in morning, sailors warning", the scientific understanding behind such occurrences remains the same.
How many of these weather sayings do you recognise and is there any truth to them?
www.metoffice.gov.uk