1) Bit of a nasty fall 2) Golf-ball comparison 3) Hard precipitation 4) Particle of ice 5) Precipitation pellet 6) Small pellet of ice 7) Storm pellet 8) Summon actress sharon 9) Water ice 10) Winter pelter Found on https://www.crosswordclues.com/clue/hailstone
(from the article `climate`) The hailstones that fall from deep, vigorous clouds in warm weather consist of a core surrounded by several alternate layers of clear and opaque ice. ... True hailstones, the third type, are hard pellets of ice, larger than 5 mm (0.2 inch) in diameter, that may be spherical, spheroidal, conical, ... Most ... Found on http://www.britannica.com/eb/a-z/h/5
Hail'stone` (-stōn`) noun A single particle of ice falling from a cloud; a frozen raindrop; a pellet of hail. Found on http://www.encyclo.co.uk/webster/H/5