Sahih Bukhari Volume 006, Book 060, Hadith Number 215.
Narrated By Abdullah (bin Mas'ud) : When the Prophet realized that the Quraish had delayed in embracing Islam, he said, "O Allah! Protect me against their evil by afflicting them with seven (years of famine) like the seven years of (Prophet) Joseph." So they were struck with a year of famine that destroyed everything till they had to eat bones, and till a man would look towards the sky and see something like smoke between him and it. Allah said:
"Then watch you (O Muhammad) for the day when the sky will produce a kind of smoke plainly visible." (44.10) And Allah further said: "Verily! We shall withdraw the punishment a little, Verily you will return (to disbelief)." (44.15) (Will Allah relieve them from torture on the Day of Resurrection?) (The punishment of) the smoke had passed and Al-Baltsha (the destruction of the pagans in the Badr battle) had passed too.