Because Philippines is above the Equator that is directly heated by the sun....:)
The climate of the Philippines is very warm, and the mountains there are not particularly tall.
In general because its colder up there.
Precipitation tends to occur as rain or snow on mountaintops because as air rises up a mountain, it cools down. When the air cools, it can no longer hold as much moisture, causing the water vapor to condense and form clouds. This can lead to rain or snow depending on the temperature at higher elevations.
Temperature decreases with altitude because pressure decreases. This is the primary reason you can get snow at low latitudes but at high elevations. At elevations above 15-20,000 feet, you can even have glaciers, which is essentially snow that falls and doesn't melt.
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".
The same reason there are waterways in every other country! Rain, melting snow on mountaintops, rivers formed from oceans, etc.
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.
It is cold at very high elevations. Most rain originates as snow at high elevation, which then melts before reaching the ground.