Rashi on Exodus 10:19/רש"י על שמות י׳:י״ט

1רוח ים is A WEST WIND.

2ימה סוף INTO THE RED SEA — I say that the Red Sea was, as to part of it, in the west opposite the whole southern side of Palestine, and was also eastward of the Land of Israel; therefore a west wind blew the locusts into the Red Sea which was in the opposite direction to the west of Egypt. Thus do we find mentioned regarding the boundaries of Palestine that it (the Red Sea) faces the east of Palestine, since it states, (Exodus 23:31) “[And I will set thy boundaries] from the Red Sea even unto the sea of the Philistines”, which means from east to west since the sea of the Philistines was in the west, as it is said of the Philistines, (Zephaniah 2:5) “the inhabitants of the sea-coast, the nation of the Cherethites (the Philistines)”.

3לא נשאר ארבה אחד THERE REMAINED NOT ONE LOCUST — not even those which they had salted — for they had salted some of them (Exodus Rabbah 13:7).