I have just finished the main quest line, and now every few hours I will fast-travel somewhere and a dragon corpse will drop out of the sky in front of me. It's always dead, the corpse is always empty, and it never decays to a skeleton or performs the Absorb Soul animation. So far I have been rained on by an ancient dragon in Whiterun, two elder ones in Riften and Sky Haven Temple, and other dragons at random times.
What has not happened yet, since I finished the main quest, is a random encounter with a living dragon. I don't know if this is related, but it seems odd. I don't remember this happening on my previous play-throughs. I have Dawnguard and Hearthfire installed, but otherwise the mods I am running are the same as I have been running for months.
Has anyone else encountered this particular problem and/or know how to stop it?