Neptune.
The cold atmosphere and temperature causes so much ice and snow-like conditions it's physically unable for any species to habitat there.
[This is my 1st Answer ever, I hope i did this correct]
Hoth
Pluto is covered with frozen gases that make snow and ice on the planet. True :) -AGC
What snow planet?
About 3/4 of a billion years ago ... the ice-ball (or snow ball) Earth, when the entire planet was covered in snow & ice, the seas frozen.
In usual text, snow-covered would probably be hyphenated - otherwise the sentence could be misinterpreted - consider the difference between the concept of "snow-covered mountains" and the sentence "snow covered mountains".
Because it's covered by a snow cap
An avalanche is like a rockslide, but on a snow-covered mountain.
Because it's covered by a snow cap
Pure As the Blood Covered Snow was created in 2003.
steep snow-covered hill, and a trigger
Snow-clad; snow-covered.
Earth