Abate

The storm abated.

Abate [uh-beyt] 
Verb 
- (of something perceived as hostile or dangerous) become less intense or widespread
- to deduct from an amount or subtract

Synonyms:

decrease, decline, diminish, subside

Usage:

1. We waited for the storm to abate.

2. The action carried out will not be sufficient to abate the odour

Antonyms:
increase, intensify