I battle with lv34 Piloswine in Mahogany Gym. it use Hail, and my attack like Flame Wheel and Surf is miss! tail whip is miss too... and when he use Blizzard to my pokemon, it hits me 5 times! that's unfair...
Only pokemon with the ability snow cloak get their evasions increased here are the pokemon with snow cloak http://pokemondb.net/ability/snow-cloak
As Pakey said, but about Blizzard...well, it gets 100% accuracy in hailstorm
Evasiveness is risen if the opponent has the ability snow cloak.
same thing with sandstorm and sand veil.