Because of Mars' very low atmospheric pressure, any water that tried to exist on the surface would quickly boil away. atmosphere as well as around mountain peaks. No precipitation falls however.

When did Mars last rain?

Once upon a time (about 3.7 billion years ago, to be exact), there was rain on Mars. In fact there was enough liquid water on the Red Planet to create vast valley networks and overflowing crater lakes. But these conditions didn't last long. The poor planet lost its atmosphere and became a frozen wasteland.

Does it snow or rain on Mars?

While the red planet's thin atmosphere and bitter cold temperatures keep these frozen clouds from ever falling in the form of rain and snow we see here on Earth, there is actually a type of precipitation on Mars. "This precipitation most likely takes the form of frost," NASA explains.