Was Aquinas wrong to deny water above the firmament, and how does Augustine read Genesis literally?

Thomas starts his paragraph in the Summa by saying we really cannot believe that there is water above the firmament, that it is written for ignorant people. But that is what the text says. Psalm 148:4 says, praise the God of the heavens and the waters above the heavens, and the heavens are called the firmament in Genesis 1 and throughout the Bible, those words being interchangeable. So a Psalm tells us there is water above the firmament. And Augustine, the very man who found it hard to give a literal interpretation of Genesis 1, is the one who, in his literal interpretation, which came before his spiritual interpretation, says that here the Bible says there is water above the firmament, and though we cannot see it, we have to believe by the authority of Scripture that it is there. That is one of my favorite passages in Augustine: no holds barred, this is what Scripture says, so this is what we will believe, taking Scripture at face value as written by the hand of God, who does not lie. Thomas, on the other hand, says there is no water above the firmament, that it was just written for ignorant people, and that is one of the reasons, among many, why I take everything Thomas says with a grain of salt, even though he is a good man and very helpful in many ways.