Intense cold?
Hi Jacob
Ceres' sub-solar temperature is ~ 230 K which is enough for a noticeable vapour pressure over exposed ice. Indeed astronomers have reported frosts on Ceres for years. Kind of like Mars on a bad day temperature wise. Because of its orbital eccentricity the sub-solar temp can vary between 240 - 220 K thus creating some seasonal variation. Recent thermal evolution models actually predict about ~ 20 km of muddy-ice for the crust.
You've hit the nail on the head.
Adam