May is our very favorite month for a Hawaii vacation. The weather tends to be great and the crowds and costs are down. Ocean conditions tend to be calmer compared to winter months. It’s practically the perfect time to visit the Hawaiian Islands.
Let’s look into weather details, festivals and much more helpful things to know to enjoy the very best Hawaii vacation in the month of May.
How’s the weather in Hawaii in May?
Temperatures
The weather in May is not as hot as the summer and early autumn months. For the islands of Oahu, Maui and Hawaii (Big) Island, you can expect the daytime high temperatures in the mid-80s Fahrenheit (roughly 29° to 30°C). The northernmost Hawaiian island, Kauai, typically experiences slightly cooler temperatures. In Kauai, you can expect daytime highs in the lower 80s (roughly 27°C).
Nighttime lows will dip to the upper 70s Fahrenheit (21-ish °C). You may want to have a light sweater or jacket on hand in the evenings.
Rain
Historically, May is not a rainy month for Hawaii. Of course it’s a good idea to be prepared for a quick rain shower by wearing quick-drying clothing when you’re out hiking or sightseeing.
More weather information
For more information about Hawaii weather, check out our guide to Hawaii weather’s patterns and forecasts.
What should you pack for a May vacation in Hawaii?
With warm, tropical weather, short-sleeves and shorts are good daytime options. For hikes and sightseeing adventures, it’s always a good idea to pack quick-drying shirts, shorts or trousers. For daytime shoes, you’ll want to wear comfortable walking or trail trekking shoes that you don’t mind getting muddy. See our guide to the essential shoes for a Hawaii vacation.
For evening wear, Hawaii is quite casual, so ladies might want to pack casual summer dresses or perhaps resort wear tops with nice shorts, skorts, and trousers. For men, we suggest that your summery shirts, like polos or short-sleeve button downs, along with nice shorts. Because the temperatures will start to dip a bit after one of Hawaii’s amazing sunsets, a light sweater would be good to have on hand. (Pro Tip: You’ll likely want to wear a sweater or jacket on your flight to Hawaii anyway. So you won’t need to pack another one.)
For our expert packing tips from our many trips to Hawaii, see our Hawaii vacation packing guide. We provide many packing details that you might not have considered or be aware of.
Hawaii ocean conditions in May
By May, the big ocean swells of winter are over. May ocean conditions tend to be relatively calm. Some seasonally-operated ocean tours begin in May.
No matter what time of the year you visit the Hawaiian Islands, you must respect the power of the ocean. It’s very, very important to know ocean safety.
Experts advise swimming at Hawaii beaches that are monitored by lifeguards. For snorkeling, I recommend you choose an organized-tour company as they are more informed of the safer spots and tend to keep an eye out for their snorkelers’ safety.
Natural Occurrences in Hawaii in May
Some special seasonal occurrences to note are:
- Lahaina Noon is a fascinating phenomenon that happens twice a year, in May and July. Lahaina Noon happens when the Sun passes directly overhead for locations on Earth in the tropics. The angle is such that an upright object, like a flagpole, will not have a shadow. See this link for the list of locations, dates and times that you can observe a Lahaina Moon in Hawaii.
- Jacaranda trees are adorned with stunning lavender-hued blooms. Jacaranda trees are typically found in the upcountry areas of the islands, such as the Kula area on the slopes of Haleakala.
- Though the humpback whale season is over, if you’re really lucky, in early May, you might see a whale lingering before their journey back to Alaska. It’s not very likely that you’ll see one, but keep a look out when you are on ocean tours. We have seen humpbacks as “late” as the first week in May.
There’s no seasonality with volcano activity, but, Kilauea has been erupting in a very interesting on-again-off-again eruption pattern. Since December 2024, there have been 18 different eruption episodes. These episodes have included lava fountains reaching heights of nearly 1,000 feet (300 meters) in the air. If this pattern continues and you’re vacationing on the Big Island, check to see what’s happening with Kilauea for your opportunity to see this incredible sight.
Hawaii Night Sky Viewing in May
Hawaii is an outstanding place to stargaze! That is due to the limited light pollution. So, do take advantage of the opportunity to see the stars.
Here are some of the top things you’ll need to know for stargazing this May:
- See this link to find moonrise and set times. Ideally, you’ll want to minimize stargazing when the moon is shining as the light washes out the visibility of fainter stars and planets.
- The Eta Aquarids Meteor Shower peaks overnight May 4-5. See this link for more information.
May Festivals and Special Events in the Hawaiian Islands
Cultural festivals offer a fantastic way to learn more about Hawaii. Here are the major cultural festivals happening this May.
Hawaii, the Big Island
May 1 – Lei Day is a statewide celebration of the Hawaiian Lei. The official Lei Day is May 1, however, celebrations might be held on other days. Here’s what we know for 2025 Lei Day:
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- Waikoloa Beach Resort is hosting several Lei Day celebrations on Saturday, May 3.
- Check with the concierge at your accommodation for other potential celebrations.
May 17-25 – Honoka’a Western Week
May 25-31 – Ka’u Coffee Festival
Maui
May 1 – Lei Day is a statewide celebration of the Hawaiian Lei. The official Lei Day is May 1, however, celebrations might be held on other days. Check with the concierge at your accommodation for potential celebrations. Here’s what we know for Lei Day 2025 on Maui:
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- May 1 – Lei Day at Maui Ocean Center
- Check with the concierge at your accommodation for other potential celebrations.
Oahu
May 1 – Lei Day is a statewide celebration of the Hawaiian Lei. The official Lei Day is May 1, however, celebrations might be held on other days. Here’s what we know for Lei Day 2025:
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- May 1 – 97th Lei Day Celebration In Kapiolani Park (in Waikiki area)
- May 1 – Hawaiian Airlines May Day 2025 at the Bishop Museum
May 7, 10, 13, 14 and 15 – 2025 World Fireknife Competition at the Polynesian Cultural Center
May 26 -Memorial Day Events – A ceremony at Punchbowl and Lantern Floating Festival are two of Hawaii’s top Memorial Day events. Check our Oahu Memorial Day Events page which will be updated for 2025 in May.
Kauai
May 1 – Lei Day is a statewide celebration of the Hawaiian Lei. The official Lei Day is May 1, however, celebrations might be held on other days. Here’s what we know for Lei Day 2025:
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- May 1 – May Day is Lei Day – The Ohana Pomroy Legacy at the Kauai Museum Courtyard
May 3 – Waipa Aina Festival 2025
May 4 – Kauai Steel Guitar Festival
May 10 – 2025 Kauai Okinawan Festival
Is the month of May a crowded time to visit the Hawaiian Islands?
Overall, May is not a busy month for visitors to Hawaii, however there are a couple of busier periods worth noting. First, Japan’s Golden Week runs through May 6, 2025, so Waikiki, in particular, tends to be a bit busier with tourists visiting from Japan.
At the end of the month, Memorial Day is observed. With the three-day holiday weekend, Hawaii can be a little busier with visitors from the US Mainland.
Final notes about visiting Hawaii in May
If you need suggestions for what to see and do on your Hawaii vacation, check out our Hawaii vacation itineraries which ensure you get to experience all the “must see and do” sights and activities.
We hope you enjoy your May visit to the beautiful Hawaiian Islands!
Sheila Beal
