Hailstorm

Currently, Minecraft has four types of weather: Clear, Rain, Snow and Thunderstorm.
Out of these four, Thunderstorm is the only one to pose any actual threat.
What about a new one, called Hail?

Hail can occur anywhere Rain or Snow can, but much more rarely. It is more likely to occur in cold or snow biomes. During Hail, small Hailstone entities will spawn. Mostly, the Hail looks like more rapidly falling Snow, but the Hailstone entities spawn
in a 16- or 32- block radius of the player. When Hailstone entities spawn, they'll fall down quickly and if any entity
is hit, the Hailstone entity will die, causing 1 point of damage (), a helmet could decrease that damage. If the Hailstone falls on ground, it will cause a small ice particle effect. This entity wouldn't cause the smoke particles on death, unlike other entities. For obvious reasons, too many of them can't spawn at once. When falling on a surface, it will cause a quiet sound respective to the material it fell on, for example, falling on iron would cause a metallic sound.

Rarely, a Giant Hailstone could spawn, causing 4x () as much damage as a normal Hailstone. It would also be physically larger. The sound produced by the Giant Hailstone would be deeper than the one by a normal Hailstone. Rarely, Giant Hailstones could cause minor damage to blocks. With a eight out of one chance, the Hailstone could drop as a Hailstone item, which, if the player had at least nine of them, could be crafted into an Ice Block, however, once in inventory, the Hailstone item would "melt", disappearing if it's been in inventory or a storage item for more than 30 seconds, because otherwise, Ice blocks would be too easy to acquire.

Apologies for the lack of pictures, and the horribly edited cover picture.