Denpasar has a high precipitation season that lasts from November to March and is dry for the rest of the year.  Maximum rain occurs in December, and the most minimum amount is in October, so if getting wet bothers you, try visiting in the summer and/or early fall (autumn).
Temperature, on the other hand, is fairly constant all year round, almost always in the seventies and eighties.

Weather will probably not deter you from departing to Denpasar, or to Bali in general, though both city and island make for excellent winter getaways for people living in colder climes.

A major event worth gearing your itinerary around would be the Bali Arts Festival , which is pretty much the greatest annual cultural tradition in the Indonesian region.  Taking place in the early summer every year, it opens with processions of costumes, dances, floats, and dolls, beginning in villages and then hitting the capital.

Entertainment in Denpasar in this period is vibrant, traditional, and nearly nonstop.  Checking out the capital during the Bali Arts Festival is an excellent way to hop into the city’s past.