Since the question posed was about the Shard WM Tower I found out the mage that created the storm cloud was known only as "The Mage of Storms", this is from The History of Dertalriosh Endaertheal'a, Volume Two, Spear of Sun's Flame Descending by Melear Kadriash'nar'a.

War Mage Kadriash along with a young unnamed female moon mage bested the Storm Mage, the War Mage GuildLeader took advantage of Kadriash's control over the cloud & a bard coined the term for the tower.. StormWill.

Kadriash become guildleader later on, and his daughter Melear followed in his footsteps.

Just a piece of info for those that were asking for it.

G.