Noah's flood? Was there rain before it?

I have recently been pointed to a fairly old article on the Canopy Theory, entitled "Does the Canopy Theory Hold Water?" from Perspectives on Science and Christian Faith, December, 1985. The purpose of the article is to examine the theory that most, or all, of the water that appeared at the time of Noah's Flood was because of a canopy of water vapor that was over the earth before the flood. The author, Thomas Key, argues pretty convincingly that this could not have worked.

I was struck by this statement in his article:

What about the assertion that there was no rain or snow prior to the Flood, and that the only way that plants were watered was by mist (Gen. 2:6) and rivers (Gen. 2: 10)? The references in Genesis do not limit the watering of plants only to a single mist or even to a series of mists and by a river or rivers. Genesis 2:10-14 describes four large rivers in existence before the numerous and complex events of the Sixth Day. These huge rivers obviously could not have come from a mere mist that occurred once or even many times. Rivers come from rains and melted snows. They also come from underground streams. However, underground streams also come from rains and melted snows. The four large rivers in Eden, which went over "The whole land of Ethiopa" [sic] (Gen. 2:13) to Assyria (Gen, 2:14) and included the Euphrates (Gen. 2:14) would have required rains, rains, and more rains over an extended period of time. No mere mist will ever do as an adequate explanation for these vast rivers, and certainly not a mere mist that occurred only a few hours or literal days before.

In other words, it must have rained before the flood. I checked, and found no statement in the early part of Genesis that says that Noah and his contemporaries had never experienced rain, although I have heard people say that they didn't.

Thanks for reading.