Imagine this, only going diagonally-up. Ripped by AJ Nitro.
the arcing snowball is an attack used by Bad Mr. Frosty in ClayFighter and ClayFighter: Tournament Edition. It's an anti air version of his snowball attack This is a charge attack, meaning that you have to hold a directional button back, then press the opposite of that directional button and the button that requires the attack to work (along with the strength of the button). In this case, you have to hold down for at least two seconds, then press up and kick (any strength will do) to use the attack.
In C2: Judgement Clay, the move returns but it's made by Frosty's evil clone Ice and it's renamed as "Stay Cool", but basically it's the same move and even with the same commands.
This move is very similar to Tiny's Arcing Medicine Ball.