You curse one creature you can see within range to feel the wrath of a winter storm. Each time the creature takes damage it also takes extra thunder, lightning or cold damage equal to your spellcasting ability ability modifier (your choice). For the duration, if the creature regains hit points or hit dice the amount is halved. If the target drops to 0 hit points before this spell ends, you can use a bonus action on a subsequent turn of yours to target a new creature that you can see within range.
At Higher Levels. When you cast this spell using a spell slot of 2nd you can maintain your concentration on the spell for up to 1 hours. When you use a spell slot of 3rd level you can maintain your concentration on the spell for up to 8 hours. When you use a spell slot of 4th level you can maintain your concentration on the spell for up to 24 hours. When you use a spell slot of 5th level you can maintain your concentration on the spell for up to 3 days.