Originally Posted by
chevvron
Are you referring to military 'colour states'? If so, they are still used.
Red is cloud ceiling (not base) less than 200ft and visibility (not RVR) less than 800m.
Correction: Red is >3/8 cloud below 200ft
or visibility (not RVR) less than 800m. But I’m unfamiliar with the flag system so can’t say whether it was the same. It seems unlikely to me that there would be different shades of yellow for 1 and 2 but ISTR that those were adopted later.
