SnorkelForecast Field Atlas / Seasonal planning

Best Places to Snorkel in December

Where to snorkel in December: compare historical wave, wind, calm-water and temperature evidence at monitored destinations worldwide.

December is summer south of the equator and winter to the north. Northern tropical escapes and southern temperate reefs both merit comparison, but Australia's tropical wet and stinger seasons demand caution.

Choose the coast and the day, not just the month. Summer does not guarantee calm water. Historical model scores reflect conditions at monitored model points—not reef quality, underwater visibility, wildlife or clearance to enter the sea.

Original comparable model evidence

December conditions by destination

These locations have a full year of comparable model observations. The table uses December data only, not the annual average; it is not a complete ranking of all the world’s reefs. Importantly, the model averages nighttime hours scored zero, so even a top place can have a modest score. This is not a percentage of safe snorkeling time.

Destinations compared
11
Countries represented
5
Observed month
Dec 2025
MODEL #01 / 11 MONITORED Cozumel Mexico 56% calm sampled hours · 28.3°C sea MODEL #02 / 11 MONITORED Key Largo USA 66% calm sampled hours · 24.8°C sea MODEL #03 / 11 MONITORED Maui USA 51% calm sampled hours · 26.0°C sea
Comparable December marine model conditions. More points means more favorable modelled conditions, not a safety rating.
Destination Model score /100 · night included Calm sampled hours Sea temperature Hemisphere
01 Cozumel Mexico · Water temperature history 26.4 56%54% calm mornings 28.3°C Northern
02 Key Largo USA · Water temperature history 26.1 66%58% calm mornings 24.8°C Northern
03 Maui USA · Water temperature history 24.1 51%57% calm mornings 26.0°C Northern
04 Bahia Honda USA · Water temperature history 23.1 46%44% calm mornings 25.6°C Northern
05 Roatán Honduras · Water temperature history 22.0 23%19% calm mornings 28.2°C Northern
06 Looe Key USA · Water temperature history 21.9 43%41% calm mornings 25.9°C Northern
07 Kauai USA · Water temperature history 20.0 0%0% calm mornings 25.9°C Northern
08 Dry Tortugas USA · Water temperature history 19.9 28%26% calm mornings 25.1°C Northern
09 Oahu USA · Water temperature history 18.7 0%0% calm mornings 26.0°C Northern
10 Kralendijk Bonaire · Water temperature history 16.7 3%4% calm mornings 28.0°C Northern
11 Mallorca Spain · Water temperature history 15.1 48%43% calm mornings 16.7°C Northern

South of the equator

Southern Hemisphere destinations

December to February is Southern Hemisphere summer, but tropical Australia may have marine stingers, wet weather and cyclone exposure. Temperate New Zealand and southern Australia can also have cool water and exposed coasts.

No qualifying southern locations in the current comparable cohort; this is not a finding that southern snorkeling is worse.

Southern locations to investigate · unranked

These existing forecast destinations do not have comparable monthly scores yet and are not recommendations for this month.

  • Jervis BayTemperate New South Wales shore snorkeling; check exposure, swell and rainfall.
  • Ningaloo ReefWestern Australian fringing reef; safe access and tide windows vary by site.
  • Great Barrier ReefQueensland tropical reefs; summer overlaps marine-stinger, wet and cyclone seasons.
  • Goat Island Marine ReserveNew Zealand temperate-water reserve; local water temperature and swell matter.

North of the equator

Northern Hemisphere destinations

December to February is Northern Hemisphere winter. Some tropical reefs remain visitable, but Hawaii's north and west shores can have dangerous surf; compare the specific coast before travelling.

  1. Cozumel26/100 · Mexico
  2. Key Largo26/100 · USA
  3. Maui24/100 · USA
  4. Bahia Honda23/100 · USA
  5. Roatán22/100 · Honduras
  6. Looe Key22/100 · USA

How to use this comparison

Historical, not a live forecast

The sampled month is part of the 1 Oct 2025–30 Sep 2026 historical window. Models are not underwater observations or predictions for next year. Follow each location report for the current forecast.

Coverage before ranking

Each listed destination meets a 12-month coverage check with at least 20 qualified days per month and 18 hourly samples per day. No partial-year comparisons or mixed scoring profiles.

What 25/100 means

The all-hours Snorkel Score includes night hours scored zero. A 25/100 score does not mean a reef is poor or 25% of hours are safe. Calm-share is a wind-and-wave threshold, also not a safety guarantee. Visibility, shorebreak and hazardous currents require local checks.

Underlying data: Open-Meteo Marine API and historical weather. View the annual comparison. Commercial listings never affect the order.