vicissitudinary

Example:Her moods were as changeable as the weather, making it hard to predict her behavior.

Definition:May be changed; likely to be different from one time to the next; unpredictable; liable to change character, form, or position.

Example:The weather was so variable that no one could predict its behavior accurately for more than a day ahead.

Definition:Capable of or tending to change; not permanent or constant; changing from one state or condition to another; liable to become different; variable.

Example:His behavior was so unpredictable that his colleagues were always on their guard.

Definition:Not able to be predicted or foreseen; not conforming to usual or expected patterns; not predictable.