Charles Ellicott Commentary Exodus 9:24

"So there was hail, and fire mingled with the hail, very grievous, such as had not been in all the land of Egypt since it became a nation." — Exodus 9:24 (ASV)

Fire mingled with the hail. —Hebrew, a fire infolding itself in the midst of the hail. (and see the comment on Exodus 9:23.)