As far as I know, Storm spells and stormsurge give no boosts to WS damage. Initially, the storm simply changes the weather, giving magical attacks the same effects as if the weather was present in the zone. This only applies to spells and magical weaponskills. Stormsurge adds an enhancement to base attributes such as str, dex, but nothing else.
The suggestion presented by Luvbunny was that all weaponskill damage of the appropriate skillchain property would get a boost from the storm spells as well, meaning firestorm would boost the damage of a physical weaponskill as long as it was of the liquefaction, fusion, or light SC properties. It would not need to be a fire elemental magical attack to gain the boost, as it currently needs to be.
