Yahya related to me from Malik that he had heard that theMessenger of Allah, may Allah bless him and grant him peace, used tosay, "When a cloud appears from the direction of the sea and then goestowards ash-Sham, it will be an abundant source of rain." (ES)
USC-MSA web (English) reference: Book 13, Hadith 5 (ES)
Arabic reference (ES): Book 13, Hadith 456 (ES)