Or HaChaim on Exodus 14:23/אור החיים על שמות י״ד:כ״ג

1 וירדפו מצרים, Egypt pursued, etc. Even though the Torah says: "the cloud remained in place" (verse 20), what is mentioned here occurred in daylight already at a time when the cloud was not as impenetrable so that the Egyptians could begin to discern where the Israelites were positioned. This enabled them to start their pursuit.