It is a type of granule de glace produced in specific conditions. Cf. this from Météo-France. So it's not really clear what the "second kind" listed as "SHPL" or "SHGS" is.
The dictionary also has neige fondue for sleet according to its British usage, which someone ought to check up on as well. Giboulée is in the dictionary as the sudden springtime shower which produces ice pellets.