Ar-Rum 30:51

Wala-in arsalna reehanfaraawhu musfarran lathalloo min baAAdihiyakfuroon

But if We should send a [bad] wind and they saw [their crops] turned yellow, they would remain thereafter disbelievers.

Should We send a (harmful) wind, and they see it (the tillage) turning yellow, then they will turn ungrateful, even after all the aforesaid (bounties of Allah).