None the wiser, the good people of Ivarstead believed it to be a blessing from the Greybeards and forevermore celebrated this day as the Rain of Bears




Sources:
Skyrim
My Skyrim pony mod
https://www.youtube.com/watch?v=PqXKcJnaVj4
http://skyrim.nexusmods.com/mods/26677
http://steamcommunity.com/sharedfiles/filedetails/?id=107533396

Original Skyrim pony horse and voice pack mod by zdzichorowerzysta
https://www.youtube.com/watch?v=tcCetcbp5oM
http://skyrim.nexusmods.com/mods/16978
http://www.skyrimnexus.com/mods/6569
http://skyrim.nexusmods.com/mods/6436

Original pony models by KPshadowsquirrel
http://kp-shadowsquirrel.deviantart.com/art/Pony-Model-Download-Center-215266264

Explosion sound effect from
http://www.mediacollege.com/downloads/sound-effects/explosion/