Weather the Storm

• WOTC Official Reminder Textofficial rules
  Storm — When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.

• WWizards of the Coast2019-06-14
  Official Ruling
  Storm counts spells cast before the spell with storm was cast. Spells cast after the spell with storm was cast but before the storm ability resolves aren't counted.
• WWizards of the Coast2019-06-14
  Official Ruling
  The copies storm creates are created on the stack, so they're not cast. Abilities that trigger when a player casts a spell (such as storm) won't trigger.
• WWizards of the Coast2019-06-14
  Official Ruling
  The storm ability and the copies it creates all resolve before the spell with storm. They resolve even if the spell with storm is countered.

Rulings via Scryfall