Hawaii is famous for sunshine, but rain is what keeps the islands so impossibly green. If you’re planning a move or a trip, understanding Hawaii’s rainy season is essential — not because it’ll ruin your plans, but because it shapes everything from where you live to what you’ll pay for rent.
The reality of Hawaii’s rainy season is nothing like what most mainlanders imagine. There are no week-long downpours. No gray, dreary skies for months on end. Hawaii’s rain is localized, often brief, and usually followed by the kind of rainbow you’ll never stop photographing.
Here’s everything you need to know about Hawaii’s weather patterns during the wet months.
September 2026: What to Expect Right Now
September marks the transition point of Hawaii’s year — the dry season (April–October) enters its final stretch, trade winds begin to ease, and the islands edge toward the wetter months ahead. Ocean temperatures remain near their annual peak at 79–82 °F. The tradeoff: September is one of the most active months of the Central Pacific hurricane season, and 2026 is proving that out. Here’s the island-by-island picture.
- Oahu: Waikīkī and the south shore remain largely sunny, though afternoon showers become more frequent than August. Honolulu averages about 0.6 inches in September (NOAA climate normals), a modest uptick from August. Trade winds can become less consistent as the wet season approaches. Ocean temperatures hold at 80–82 °F.
- Maui: The south and west coasts stay in dry-season mode through October. The road to Hana and Haleakālā’s windward slopes see afternoon showers as usual. September water conditions remain excellent for snorkeling on the leeward coast.
- Big Island: Kona, Waikoloa, and the Kohala resorts remain dry. Check the USGS Hawaiian Volcano Observatory status and the vog forecast map before booking leeward Big Island if you have respiratory sensitivities — trade-wind stalls that allow vog to build can occur in September.
- Kauai: Poipū and the south shore remain reliably sunny. The north shore and Na Pali interior see their usual windward showers. September boat tours from Port Allen or Kīkiaola Harbor generally run on calm seas, though swells can arrive with early-season storm systems.
Hurricane season — active threat now: August and September are the statistically most active months of Hawaii’s hurricane season (June 1–November 30). Active as of September 6, 2026: Hurricane Lowell (Category 3) is approximately 596 miles south-southwest of Lihue, moving north-northwest at 6 mph — a hurricane watch is in effect for parts of Hawaii. Tropical Storm Karina is approximately 717 miles from Hilo, moving northwest and posing no direct threat at this time. Track all active systems and official watch/warning areas at the NOAA Central Pacific Hurricane Center.
When Is Hawaii’s Rainy Season?
Hawaii’s rainy season — called “ho’oilo” in Hawaiian — runs roughly from November through March. The dry season (“kau”) covers April through October.
But calling it a “rainy season” is a bit misleading. It’s not like Southeast Asia where monsoons dump rain for weeks straight. The difference between seasons in Hawaii is more subtle:
- December and January are the wettest months across most islands
- June and July are typically the driest
- Average temperatures only drop about 5–8°F between seasons (highs of 80–85°F in summer vs. 75–80°F in winter)
- Rain often falls in short bursts — 15 to 30 minutes — then clears up
The real story isn’t when it rains — it’s where.
Windward vs. Leeward: The Side of the Island Matters More Than the Month
This is the single most important thing to understand about rain in Hawaii: the side of the island you’re on makes a much bigger difference than the time of year.
Every Hawaiian island has a windward side (facing northeast, toward the trade winds) and a leeward side (facing southwest, sheltered from the trades). The windward side gets dramatically more rain — year-round.
How Trade Winds Create Rain
Northeast trade winds carry moisture from the Pacific Ocean. When that moist air hits a mountain, it’s forced upward, cools down, and releases rain on the windward slopes. By the time the air crosses over to the leeward side, it’s already lost most of its moisture.
This is called orographic rainfall, and it creates some wild contrasts. On the Big Island, Hilo (windward) gets about 130 inches of rain per year — making it the wettest city in the United States. Meanwhile, the Kohala Coast resort area (leeward) averages just 10 inches annually. Same island, completely different climate.
Rainfall by Island: Where It Rains Most (and Least)
Oahu
Wettest areas: Windward side — Kailua gets about 50 inches/year, but the Ko’olau mountains behind it can top 250 inches. Mānoa Valley in Honolulu averages 150+ inches.
Driest areas: Waikīkī and the Ewa Plain average just 17–20 inches/year. If you’re staying in Waikīkī, you’ll barely notice the rainy season.
Pro tip: if you’re hiking on Oahu, trails on the windward side (like the Maunawili Falls Trail) will be muddier during rainy season. Plan your hikes for the morning when skies are usually clearest.
Maui
Wettest areas: The road to Hana and the northeastern slopes of Haleakalā. The Hana area averages 80+ inches/year.
Driest areas: Kīhei, Wailea, and Lahaina (West Maui) average 10–15 inches/year. These resort areas are practically desert-like compared to the lush east side.
Big Island (Hawai’i)
Wettest areas: Hilo and the Hamakua Coast are consistently drenched — 130+ inches/year in Hilo. The slopes of Mauna Kea and Mauna Loa on the windward side can see over 200 inches.
Driest areas: Kona Coast and the Kohala resorts (Waikoloa, Mauna Lani) average just 10–26 inches/year. This is why most Big Island resorts are on the west side.
The Big Island is extreme — it contains 10 of the world’s 14 climate zones, from tropical rainforest to subarctic at the summit of Mauna Kea.
Kauai
Wettest areas: Mount Wai’ale’ale is one of the wettest spots on Earth, averaging about 450 inches (37 feet!) of rain per year. The North Shore and the interior are consistently wet.
Driest areas: Poipū on the South Shore averages about 30 inches/year and is one of the sunniest spots in Hawaii. Waimea on the west side is also relatively dry.
What Does Rainy Season Actually Feel Like?
Forget everything you know about “rainy seasons” from other places. Here’s what rain in Hawaii is actually like:
- Short showers: Most rain falls in quick 10–30 minute bursts, not all-day soakers
- Warm rain: Water temperatures hover around 75°F even in winter, so getting caught in a shower is more refreshing than miserable
- Highly localized: It can be pouring in Mānoa Valley while Waikīkī (3 miles away) is bone dry
- Morning clearing: Mornings are usually the driest part of the day; rain tends to build in the afternoon
- Rainbows everywhere: Hawaii is literally called the “Rainbow State.” The combination of frequent showers and sunshine makes double rainbows a regular occurrence
The most disruptive weather during rainy season comes from Kona storms — low-pressure systems that bring winds from the south or southwest (the opposite of normal trade winds). These can dump heavy rain on normally dry leeward areas and cause flooding. They happen maybe 3–5 times per winter and usually last 2–3 days.
How Rainy Season Affects Daily Life in Hawaii
Housing and Rent
Rain patterns directly affect real estate prices. Leeward, sunny areas command higher rents. A 2-bedroom in dry Kailua-Kona now averages around $2,800/month (as of June 2026), while a similar 2-bedroom in rainy Hilo runs about $2,200/month. The windward side still offers cheaper housing — but the gap has narrowed considerably over the past year.
If you’re looking for affordable places to live, check out our guide to renting in Hawaii.
Outdoor Activities
Rainy season doesn’t shut down outdoor life — it just shifts your timing. Surfers love winter because the North Shore swells pick up massively (this is when the famous Pipeline and Waimea Bay competitions happen). Camping is still doable, though windward campgrounds get soggy.
Whale watching season (December–April) coincides almost perfectly with rainy season. Humpback whales migrate to Hawaii’s warm waters to breed, and you can often spot them from shore — rain or shine.
Driving
Flash floods are the main concern during heavy rain events. Streams that are bone-dry in summer can become raging torrents within minutes. Never cross a flooded road or stream. The North Shore of Oahu’s Kamehameha Highway occasionally floods and closes during big storms.
Tips for Dealing With Hawaii’s Rainy Season
- Stay on the leeward side if you want maximum sunshine — Waikīkī, Kīhei, Kona, Poipū
- Pack a light rain jacket — umbrellas are less practical in trade winds
- Plan outdoor activities for the morning — rain usually builds in the afternoon
- Download a radar app — the Windy app or Weather.gov Hawaii radar lets you see exactly where rain cells are in real time
- Embrace it — some of Hawaii’s most magical moments happen right after a rain shower (think waterfalls at full force, rainbows over the ocean)
- Check surf conditions — winter swells mean amazing surf watching even if you don’t surf
- Drive carefully — roads get slick and visibility drops fast in tropical downpours
Best Time to Visit Hawaii to Avoid Rain
If rain is a dealbreaker for you, aim for June through September. These are the driest months across all islands. For a fuller calendar of tradeoffs across weather, prices, and crowds, see our guide to the best month to visit Hawaii. But honestly? Even during peak rainy season, most visitors barely notice the rain — especially if you’re staying in a leeward resort area.
The “worst” month for rain is typically December, but even then, Waikīkī averages only about 3 inches for the entire month. That’s less than most mainland cities get in their driest month.
One caveat for late-season planners: Hawaii’s hurricane season overlaps with the tail end of summer through November, so August–October trips carry a small risk of tropical-storm-related disruptions. For more on what to expect weather-wise before making the move, read our full Hawaii weather guide.
Frequently Asked Questions
Does it rain every day in Hawaii during rainy season?
No, not even close. Even during the wettest months, most areas — especially leeward resort zones — see sunshine for the majority of the day. Windward areas might get daily showers, but they’re usually brief. Many days during “rainy season” are completely dry and sunny.
What is the rainiest month in Hawaii?
December is generally the rainiest month across most Hawaiian islands. January and February are close behind. However, rainfall varies dramatically by location — a rainy month in Waikīkī still means less total rain than a dry month in Hilo.
Should I avoid visiting Hawaii during rainy season?
Absolutely not. Winter (November–March) is actually one of the best times to visit. Hotel rates are lower than peak summer, whale watching season is in full swing, the North Shore surf is pumping, and the rain rarely disrupts plans. Just stay on the sunny leeward side and you’ll be fine.
Which Hawaiian island gets the least rain?
The Big Island’s Kohala Coast (Waikoloa/Mauna Lani area) and Maui’s Kīhei/Wailea coast are the driest populated areas in Hawaii, averaging just 10–15 inches of rain per year. Lāna’i is also notably dry, averaging about 15–18 inches annually on its leeward coast.