Well, that's just a psycological referrence to the bombardment. Of course fog and heavy rain aren't the results of plasma bombing, but it gives the sunny place a much more heavier environment and tension after-bombing.
But I too preferred Kotor I Dantooine over Kotor II one. See, it's just like Korriban on both games: The first one had an academy, quests (a lot), different groups fighting, some challenging creatures and the rest. But everything we see on the two is recycled planets, with a few new areas and a lot of cut old areas.
