Albert Barnes Commentary Exodus 14:21

"And Moses stretched out his hand over the sea; and Jehovah caused the sea to go [back] by a strong east wind all the night, and made the sea dry land, and the waters were divided." — Exodus 14:21 (ASV)

A strong east wind - The agency by which this was effected was natural (Compare to Exodus 15:8 note), and the conditions of the narrative are satisfied by the hypothesis that the passage took place near Suez.

The waters were divided - That is, there was a complete separation between the water of the gulf and the water to the north of Kolsum.