Exodus Chapter 9 Verse 24 - 35
24.) So there was very severe hail, and lightning mixed with the hail, such as had not been in all the land of Egypt since it became a nation.
25.) The hail struck throughout all the land of Egypt all that was in the field, both man and animal; and the hail struck every herb of the field, and broke every tree of the field.
26.) Only in the land of Goshen, where the children of Israel were, there was no hail.
27.) Pharaoh sent, and called for Moses and Aaron, and said to them, "I have sinned this time. Yahweh is righteous, and I and my people are wicked.
28.) Pray to Yahweh; for there has been enough of mighty thunderings and hail. I will let you go, and you shall stay no longer."
29.) Moses said to him, "As soon as I have gone out of the city, I will spread abroad my hands to Yahweh. The thunders shall cease, neither shall there be any more hail; that you may know that the earth is Yahweh's.
30.) But as for you and your servants, I know that you don't yet fear Yahweh God."
31.) The flax and the barley were struck, for the barley was in the ear, and the flax was in bloom.
32.) But the wheat and the spelt were not struck, for they had not grown up.
33.) Moses went out of the city from Pharaoh, and spread abroad his hands to Yahweh; and the thunders and hail ceased, and the rain was not poured on the earth.
34.) When Pharaoh saw that the rain and the hail and the thunders were ceased, he sinned yet more, and hardened his heart, he and his servants.
35.) The heart of Pharaoh was hardened, and he didn't let the children of Israel go, just as Yahweh had spoken through Moses.