What to look for in nature in Hawaii this December

Yes, and December is when the chorus begins in earnest. NOAA’s humpback sanctuary for the islands says that from December through April the song of male humpbacks becomes the dominant background sound underwater in many parts of the islands, and that a single singer can be heard several miles away. The sanctuary uses that sound to track how many whales are around. Recorders at six sites off Maui put the loudest stretch in February and March, so December is the overture.

The whales come to breed, not to eat. NOAA Fisheries says the North Pacific animals build up blubber on their summer feeding grounds in Alaska and western Canada and live off it through the winter, and that some cover the 3,000 miles from Alaska to Hawaii in as few as 28 days. Calves are born here after a pregnancy of about 11 months, already 13 to 16 feet long, so a mother with a calf later this winter may well have mated in these same waters a year before.

A puzzle for this winter: after the 2014–15 season, those Maui recorders picked up less than half as much song energy in the peak months, coinciding with a marine heat wave in the North Pacific and the strong El Niño that followed. The authors could not say whether fewer whales came, whether they arrived later, or whether they behaved differently. With another powerful El Niño building, the chorus is worth listening to closely.

In November and December, so this is the month of sitting still. DLNR’s species account gives those two months for egg laying, a single egg per pair, and July for the chicks to leave. Audubon’s field guide puts incubation at an average of 64 to 65 days, shared by both parents, which means the eggs laid this month will start hatching around late January and February. While one bird sits, its mate may be away feeding at sea for days at a time, sometimes weeks; when it returns, the pair swap places and the hungry one heads out to feed.

Birds with eggs have mostly stopped dancing; the dancers still on the colony are largely young birds that have yet to breed.

Counting opens Monday, December 14, and closes Tuesday, January 5, 2027. Every circle, 15 miles wide and fixed from year to year, gets one count day, when teams follow set routes and record every bird they see or hear. Hawaiʻi Audubon Society lists circles on Oʻahu, Hawaiʻi Island, Maui, Lānaʻi, Molokaʻi and Kauaʻi, and asks newcomers to sign up ahead of time with each circle’s compiler for a route and a day. Last season the Waipiʻo circle in central Oʻahu counted on December 14, 2025, and the Honolulu circle on January 4, 2026; the compilers usually announce this winter’s dates in late fall.

The results are surprisingly rich. In the 124th count, the Honolulu circle tallied 3,143 red-footed boobies and 169 white terns, the manu-o-Kū that nest in city trees; Kapaʻa on Kauaʻi found 351 Hawaiian ducks; North Kona logged an ʻiʻiwi; and a white wagtail turned up as a first record for the state. Two seasons earlier, Līhuʻe counted 148 nēnē, a record, and Midway reported 1,855 kōlea.

On the high summits, yes. The Center for Maunakea Stewardship at the University of Hawaiʻi at Hilo says it usually snows on Maunakea a few times a year. On January 5 and 6, 2026, a storm left 8 to 10 inches around the summit, and snow also showed on webcams on Mauna Loa; the road closed while crews brought out a snow blower, two plows and a loader. A December 21, 2022, storm was worse, with winds over 100 mph, sleet, freezing rain and more than 6 inches of snow that set into hard ice and drifts, closing the road for days.

The long-term numbers say how rare real cold is. At the Mauna Loa slope station near the observatory, about 11,000 feet up, the 1991–2020 normals give 4.4 nights in an average December at 32 °F or below, rising to 6.3 in January and 9.1 in February. The ranger station on Haleakalā, near 7,000 feet, averages none. The summits above both are colder still, and every station in the table below, from sea level to 7,000 feet, averages no freezing nights at all.

Maunakea is among the most sacred places in Hawaiʻi; the stewardship center asks visitors to treat it that way, snow or no snow.

Very, on the windward side, and wetter than most visitors expect almost everywhere else. In a normal December Hilo gets about 12 inches, with a tenth of an inch or more falling on about 16 days. Līhuʻe and the Haleakalā ranger station get more rain in December than in November, and even dry Kahului and Kona pick up. Honolulu’s December normal is a modest 2.18 inches. Temperatures barely move: Honolulu airport averages about 82 °F by day and 69 °F at night.

The big rains of Hoʻoilo usually come with Kona lows, slow storms that pull moist southerly winds across the islands and soak the leeward sides that the trade winds leave dry, and with cold fronts that sweep in from the northwest with a band of heavy showers and a shift to cool northerly winds behind. The Western Regional Climate Center notes that the number of Kona storms varies widely from one winter to the next.

Our cloud forecast shows when a band of showers is due, and the current conditions page lets you watch the wind swing round and the pressure dip as a Kona low comes near.

It may well, though December itself is the least likely month to show it. The Climate Prediction Center’s mid-September update rated the chance of an exceptionally powerful El Niño lasting through the islands’ cool season at better than ninety percent. NOAA’s Pacific ENSO Applications Climate Center notes that these events tend to peak in December, which is how the name, the Spanish for the Christ Child, came about. For Hawaii it sums up the usual effect as more rain at the start of the wet season and then rapidly less, along with weaker trade winds that can turn westerly at times.

DLNR’s drought program puts the chance of drought during the wet season after an El Niño at about 70 percent, with below-normal rain common through the following winter and spring. When a strong event was building in 2023, the Honolulu forecast office’s wet-season outlook warned of rain-fed pasture and crops drying out, catchment tanks running low, brush fires out of their usual season, and a better chance of large north shore surf, especially in January and February. It also reminded readers that a single downpour can still bring a flash flood in a dry winter.

NOAA’s winter outlook is due out on October 15, and its maps for Hawaii will appear with the rest on the Climate Prediction Center’s 90-day outlook page. The Honolulu forecast office usually issues its own wet-season rainfall outlook for the state in mid-October as well.

On Haleakalā, the park’s free Forest Bird Hikes go on into December, on Tuesdays and Wednesdays, December 1, 2, 8, 9, 15 and 16, from 9 to 10 a.m. A park biologist leads each one from the picnic shelter at Hosmer Grove, near 7,000 feet, into the native shrubland and forest edge where ʻapapane, ʻiʻiwi and ʻamakihi feed. Come in a warm layer and a rain shell; December mornings up there average in the mid-40s.

Nēnē are deep in their breeding season. DLNR says most clutches are laid between October and December and take about a month to hatch, so goslings hatch all through the winter. The national park on Kīlauea closes sensitive brooding areas to protect young families and says cars kill more adult nēnē in the park than anything else.

Clean your boots before and after any native forest walk. Rapid ʻŌhiʻa Death spreads on soil and wood, and a quick brush and a spray of rubbing alcohol is how hikers help stop it.

Two very different plants stand out this month: a native tree the forest birds depend on, and an invasive shrub dressed like a holiday decoration.

Barely. Sitting between 19 and 22 degrees north, the islands have the longest winter days of any state: about 10 hours 48 minutes in Līhuʻe at the solstice and 10 hours 57 minutes in Hilo and Kona. From December 1 to the solstice, the cities in the table give up only four to six minutes, and by New Year’s Eve most have won back a minute or two.

The odd part is the timing. The earliest sunsets have already come and gone: Honolulu’s sun sets at 5:48 p.m. from about November 21 to December 1, with the true minimum around November 26, and by December 31 it sets at 6:01. The mornings go the other way, and Honolulu’s sunrise slips from 6:53 a.m. on December 1 to 7:09 on the last day of the year, reaching its latest, 7:12, in mid-January. So a December evening walk gets a little more light each week, while the walk to the school bus gets darker.

To find first and last light for your own beach, valley or lookout, drop a pin in the sunrise and sunset calculator.

Times are Hawaii Standard Time. December brings the year’s best meteor shower with almost no moon in the way, and the biggest-looking full moon of 2026. The solstice, when the sun stands farthest south, comes at 10:50 a.m. on Monday, December 21.

Before you set an alarm for 2 a.m., check whether trade-wind showers will clear on the sky and cloud outlook, and look up rise and set times for your island on the moon phase calendar.

1. Walk with a park biologist looking for honeycreepers at Haleakalā’s Hosmer Grove on December 1, 2, 8, 9, 15 or 16, 9 to 10 a.m. The hike itself is free; bring binoculars and a jacket.
2. Pull weeds in the rainforest. Hawaiʻi Volcanoes National Park lists a volunteer restoration morning on Saturday, December 5, 8:45 a.m. to noon (check the park calendar for later Saturdays), meeting at the Kīlauea Visitor Center parking lot. Wear closed shoes, long pants and rain gear; the park provides tools and gloves, and volunteers under 18 come with a parent or guardian.
3. See feathers become art. Every Wednesday in December (the 2nd, 9th, 16th, 23rd and 30th), Puʻukoholā Heiau National Historic Site on the Kohala coast offers a demonstration of hulu aliʻi, chiefly featherwork, at the visitor center from 10 a.m. to 1 p.m. A good way to talk with children about the forest birds whose feathers made royal cloaks.
4. Watch a fishpond wall go up. At Kaloko-Honokōhau National Historical Park, stone-setter Benson Chong demonstrates traditional dry-stack wall building on Wednesday, December 16, 10 to 11 a.m.
5. Visit Waimea Valley on a royal birthday. The valley marks Prince Lot Kapuāiwa’s birthday on Friday, December 11, and Princess Bernice Pauahi Bishop’s on Saturday, December 19, with half-price admission for kamaʻāina with a state ID, 9 a.m. to 4 p.m.
6. Join a bird count. Ask Hawaiʻi Audubon to match your family with a Christmas Bird Count team, or start a Kōlea Count of your own yard on December 1.
7. Stay up for the Geminids on December 13, or watch the Cold Moon rise at sunset on December 23.
8. Greet 2027 at Makapuʻu. For years Hawaii State Parks has led a First Day Hike on the Makapuʻu Point Lighthouse Trail at Kaiwi State Scenic Shoreline on New Year’s Day, with the pū blown to the four directions, chant and taiko at sunrise; on January 1, 2026, gates opened at 5:30 a.m. for about a mile of paved trail to the overlook. Watch DLNR’s state parks announcements in December for the 2027 details, and bring a flashlight and a warm layer.

The Naturalist’s Field Journal is made for a family’s winter notes, and the index of month-by-month nature guides covers other states. Last month’s page for the islands is at November in Hawaii.

• Kauaʻi’s state parks. After Hurricane Lowell, DLNR reopened only a few Kauaʻi lands in late September. Waimea Canyon and Kōkeʻe state parks, Hāʻena and Polihale, and the Nā Pali Coast wilderness park with the Kalalau Trail remained closed with no reopening date, and Kōkeʻe Road was still shut. Check DLNR’s latest notices before planning any Kauaʻi hike.
• Ice and snow up high. Freezing fog, ice and snow can close the Maunakea summit road with little warning, and Haleakalā’s summit can drop below freezing on winter mornings. Go up with a full tank, warm clothes and gloves, and turn back if the weather turns. Altitude sickness is a real risk above 9,000 feet.
• Flash floods. A Kona low or a stalled front can turn a dry streambed into a torrent in minutes, even when it is not raining where you stand. Do not cross flowing water on foot or by car, and stay out of the ocean near stream mouths after heavy rain. Leptospirosis is a risk in fresh water, especially with cuts.
• Winter surf. North- and west-facing shores take the biggest swells of the year. Watch from well back, keep off wet rocks and ledges, swim only at guarded beaches, and believe the lifeguards’ signs.
• Kīlauea. As of October 1, Halemaʻumaʻu’s vents were still glowing and spattering after 54 fountaining episodes since December 2024, the alert level stood at WATCH, and the volcano observatory said a 55th episode could come. Read the daily update before you go, and avoid vog if you have heart or lung trouble.
• Short days. Most of the month the sun is down between about 5:40 and 6 p.m., earliest in Hilo, and twilight is brief this close to the tropics. Start long hikes early and pack a headlamp.
• Hunting seasons and blaze orange. Under the state’s game bird rules, the season runs from the first Saturday in November to the last Sunday in January, in 2026–27 from November 7 to January 31, mostly on weekends and state holidays; DLNR had not posted its unit-by-unit announcement for the season by early October. On Kauaʻi, bowhunters may take deer daily in Unit F, and on Saturdays, Sundays and state holidays in Units J and K, until the end of December, and in Unit D archery deer hunting runs alongside the regular pig season on weekends and holidays through December. Pig and goat hunting is open all year in many units statewide. Where firearms are allowed, hunters and anyone with them, guides, helpers and companions alike, must wear an outer shirt, vest, jacket or coat in commercially made blaze orange (solid fabric, or mesh with openings of an eighth of an inch or less) that can be seen from front and back; any orange camouflage pattern is banned. Hikers in hunting areas are wise to wear something bright too.