Another interpretation of flood stories would be consistent with a large plasma phenomenon, such as a meteorite impact, or (though unpopular, and mostly wrong) Velikovskian discharges between planets, with EDM going on.

Ignoring some of the Velikovskian flak, meteorites might display similar phenomena, though not as long-lastingly or stably as a plasma discharge between bodies.

Long story short, most "flood stories" describe "waters from heaven," but make a definite distinction between heavenly "water" and regular water. Generally heavenly "waters" were fire-like, and the "waters" were often accompanied by a rain of salt, or "brimstone" or "sand/gravel." This is generally consistent to SOME degree with meteorites, in terms of breaking up into tiny, tiny pieces which would probably resemble said sand/gravel/brimstone/salt.

However, meteorite impacts are generally too small/transient in my opinion for the widespread devastation of the world. Perhaps local devastation, certainly, and the plasma would certainly seem fire/water-like, to those who don't understand what it is.

However, if one stray into the EU model (taking it to the next extreme) briefly, don't worry, we'll come back to sanity eventually, their viewpoint is that the "axis mundi," (or world axis, pillar of the gods, pillar of the sun, world tree, etc.) which is a GLOBAL mythology not confined to any one region, is actually a mythological counterpoint to a very real giant plasma/electrical discharge between planets which may have occurred during early human history. It was generally described as a pillar of light, leading to "the sun" (or at least a large glowing orb in the sky, which may or may NOT have been the current sun, according to the EU model there are a few intereting, if vague, references in mythology to the "true sun" as if there were at some point more than one stellar body that may have filled that role). And the mythology basically said that if the pillar or tree were ever uprooted or moved its waters would flow forth doing great devastation to whatever they touched. Again, with the attendant fire/water duality and sand/gravel, or salts accompanying the discharge of the heavenly "waters." EU model says this was a giant plasma discharge between charged bodies, involving EDM machining among other things (literally breaking up the ground on one body, slicing and dicing it and transporting it wholesale as sand/gravel to another body). But, that's yet to be fully researched/substantiated.

Getting back to the main point, a plasma discharge from a meteorite might transiently meet some of the descriptions of "flood stories," including the fire/water duality and the sand/gravel references that generally accompany flood stories. And the impact of the object or the shockwave from its explosion/breakup in the atmosphere could potentially cause said tsunamis, and/or other oddities of biblical and other similar stories.

And, if they watched the skies at all, and were somewhat lucky in their observations, they might have seen a comet or asteriod develop a coma and thus "seen it coming." Of course if one takes the EU model seriously (I'm still not totally sold on all aspects of it, though a few are interesting), it would certainly be hard to miss the 'axis mundi' or any changes or movement of it. Considering it seemed to be well known to be dangerous and/or deadly if it was "uprooted."

But again, just another oddball explanation to deal with some oddball anomalies in the historic and/or mythohistoric record. But, if we look at accounts of the Tunguska event, in some regards, they bear striking resemblance to "flood" mythology... I'm sure quite a few that witnessed it thought the world was ending... ;o] Houses collapsing of their own accord, people suddenly being knocked to the ground by some unseen force, intense heat everywhere, a sound like barrages rockets going off everywhere, trees suddenly bursting into flames and being flattened.

Anyway. All sorts of oddball fun.