Here are some other ways to describe it:
* Whimsical: Impulsive, unpredictable, and often charmingly playful.
* Fickle: Changing frequently, especially as regards one's loyalties or affections.
* Erratic: Not regular or consistent; unpredictable.
* Mercurial: Subject to sudden or unpredictable changes of mood or mind.
Examples:
* "The capricious weather made it difficult to plan outdoor activities."
* "Her capricious nature made it hard to know what to expect from her."
* "The stock market is often capricious, with prices fluctuating wildly."