´It was narrated that Ibn Abbas said:` "The Messenger of Allah said; 'Fast when you see it and stop fasting when you see it, and if it is obscured from you (too cloudy), then complete thirty (days)."'
Hadith ReferenceSunan an-Nasa'i / The Book of Fasting / Hadith: 2126
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:إسناده صحيح