Our first trip to Kaua'i was many years ago and we splurged and rented a convertible. We were staying near Prince Kuhio Park (Poipu area) and figured we'd have nice weather "most" of the week. Well, it rained 5 of the 7 days we were there.

Plenty to do even if it rains. Kids are less picky than adults.
Rain is forecast for the next 10 days. Hiking is dangerous when the trails are wet. Be careful.
https://www.wunderground.com/forecas...=localwx_10day