The best time to visit Kauai depends on what you want from the water. Ask the crews at Port Allen and you get two answers. The captains love summer, when the ocean goes flat and the boats get into the sea caves. The whale watchers love winter, when the humpbacks are breaching off every harbor and the north shore surf is huge.
Here is how the year actually goes, from people who are out on it every day.
The short version
- Best overall: April, May, September and October. Calm seas, the Hanalei boats running, fewer people, lower prices.
- Best for the sea caves and snorkeling: June through September. The flattest water of the year on every coast.
- Best for whales: January and February, with the season running December to March.
- Best value: late April to mid June and September to early December, outside the holidays.
- Watch out for: the north shore in winter, when the surf closes Hanalei Bay to boats and the beaches to swimmers, and hurricane season, June to November, which rarely matters but is worth insurance.
Water temperature and swell by season
| Months | Water temp | What the ocean is doing |
|---|---|---|
| Dec to Mar | 74 to 76°F | Big north swells. North-shore beaches dangerous, Hanalei boats stopped. South and west shores calm. Whales everywhere. |
| Apr to May | 76 to 78°F | Swell fading. Hanalei boats restart. Snorkeling returns to Nā Pali. |
| Jun to Sep | 79 to 81°F | Flat, warm, clear. Sea caves open, Tunnels snorkelable, best season on the water. South shore gets its own small summer swell. |
| Oct to Nov | 78 to 79°F | First north swells arrive. Hanalei runs sightseeing-only, then stops. Whales return in November. |
Month by month
January and February
Peak whale season and peak winter. Daytime highs around 78°F, cool nights, and rain on the north shore most days. The north swells are at their biggest, which closes Hanalei to boats and makes the north-shore beaches dangerous; swim at ʻAnini, Poʻipū or Salt Pond instead. The Nā Pali boats run from Kekaha and Port Allen with whale watching in place of snorkeling, and the Kekaha catamaran is the calmest ride. The helicopter sees waterfalls at full volume. Book the tubing for a rainy day. Holiday and President’s Day weeks are expensive.
March
Whales still here but thinning out, swell easing. The Hanalei season starts in March in a good year, so the Hanalei catamaran becomes possible, with cancellations still common. Spring break brings families and the tubing sells out; book it before you fly.
April and May
Our favorite months. The swell is gone, the water is warming, the Hanalei boats are running, the Nā Pali rafts are getting into the caves again, and the crowds and prices drop after Easter. The island is at its greenest after winter rain. The Wailua kayak has a full waterfall and a dry trail.
June, July and August
Summer: flat, warm, sunny and busy. This is the best season on the water by a distance. Every Nā Pali boat is running, the sea caves are open on most mornings, the snorkel stops happen, and Tunnels and Kēʻē on the north shore are calm enough to snorkel from shore. The trade-offs are families everywhere, the highest room rates outside Christmas, and afternoon trade winds that make the morning departures the smart ones. The raft is at its best now.
September and October
The locals’ summer. The water is at its warmest, the ocean is still flat into early October, the kids are back in school and prices fall. Hurricane season is technically open but Kauai sees a real threat about once a decade; buy insurance and do not worry. The first north swells arrive in late October, when the Hanalei boats switch to the shorter sightseeing tour.
November
The shoulder. Rain picks up on the north shore, the swell builds, and the first whales arrive in the second half of the month. Hanalei runs sightseeing tours when the bay allows; Kekaha and Port Allen run every day. Thanksgiving week is busy; the two weeks either side are quiet and cheap.
December
Whale season proper, winter swell, and the holidays. The first three weeks are calm and good value; Christmas to New Year is the most expensive and crowded stretch of the year, and every tour on this site sells out. If you are coming for the holidays, book the boats, the helicopter and the tubing the day you book the flights.
Which tours to book when
- Any month: the Kekaha boat, the Port Allen raft, the helicopter, the Wailua kayak on weekdays, the zipline and the tubing.
- March to December only: the Hanalei catamaran, with snorkeling March to September.
- December to March only: whale watching on any Nā Pali trip.
- June to September for: sea cave entries, snorkel stops and shore snorkeling at Tunnels.
A note on rain
Kauai is the wettest of the main islands and the north shore is the wettest part of it, but the rain is local. Waiʻaleʻale gets 450 inches a year; Poʻipū gets about 35. A rainy morning in Hanalei is usually a sunny one in Kōloa, 90 minutes away. If the forecast is wet, go south and west, or go tubing. For where to base yourself by season, see the regions map, and for the full list of trips, the ranked list.
Written by Kauai locals who spend their days on the water and the trails. How we make money.
