Yes, you can snorkel in Key West in winter, and the boats run every month. From November to February the water at NOAA’s Key West harbour gauge averages 78.3 °F in November, 75.3 °F in December, 72.5 °F in January and 73.8 °F in February, and the reef offshore can dip into the mid-60s °F after a cold front. Days are mild and dry, with average highs in the mid to upper 70s °F. The catch is wind: winter cold fronts make the seas rougher, and an operator will move a trip when it is unsafe to go out. Wear a wetsuit in January and February if the boat has one, and book your snorkel day early in your stay.
Some trips plan for the cold. Danger Charters’ Half-Day Trip with Kayaking, Snorkeling and Sunset lists “comfortable wetsuits for the winter months” among its inclusions. It sails a schooner limited to 20 guests from the base of Opal Key Resort & Marina, runs four and a half hours and costs from $125 per person (checked November 2026), with 4.9 from 1,832 reviews on Viator. Our review explains the day.
Half-Day Trip from Key West with Kayaking, Snorkeling & Sunset
- 4.9/5 (1,832 reviews)
- About 4.5 hours
- Free cancellation
- Operated by Danger Charters
Includes Use of snorkeling equipment · Wetsuits for the winter months · Professional guide
You'll choose your date and complete the booking on Viator. Free cancellation under Viator's standard terms; the booking page shows the deadline.
Winter water and air temperature
The table puts the four winter months and March side by side. Water figures are NOAA’s long-term monthly means for the Key West harbour gauge. Air figures are National Weather Service 1991-2020 normals; the NWS publishes two Key West tables that differ by a degree or two, so each figure is the range across both. Rain is from the NWS Key West table.
| Month | Water (mean) | Average high | Average low | Rain |
|---|---|---|---|---|
| November | 78.3 °F (25.7 °C) | 80.6 to 81.0 °F | 69.8 to 72.2 °F | 3.28 in |
| December | 75.3 °F (24.1 °C) | 76.9 to 77.7 °F | 66.0 to 68.3 °F | 2.22 in |
| January | 72.5 °F (22.5 °C) | 74.7 to 75.8 °F | 62.9 to 65.5 °F | 2.01 in |
| February | 73.8 °F (23.2 °C) | 76.5 to 77.4 °F | 64.3 to 67.1 °F | 1.96 in |
| March | 75.9 °F (24.4 °C) | 78.8 to 79.6 °F | 66.8 to 69.3 °F | 1.41 in |
Two caveats sit behind the water numbers. The gauge is in the harbour, so reef water can differ by a few degrees. And single winters run cooler than the long-term average: in January 2025 the gauge averaged about 70 °F, with a lowest reading of about 65 °F. Fury Water Adventures says its reef water “can dip into the mid-60s” in winter. Our water temperature by month page has the whole year.
Cold fronts, wind and trips that do not go
Fronts are the winter story. The National Park Service, describing the weather around the Dry Tortugas west of Key West, says winter cold fronts push cool, dry air south and bring cooler, windier conditions, and that winter is typically windier than summer, so seas are usually rougher. The Key West harbour gauge shows the same thing in its average wind: about 8 to 10 knots from January to April, against about 5 to 6.5 knots in July and August. It is a sheltered gauge, so the open water is windier still.
What that means for you:
- A front can make the boat ride out to the reef choppy. Low-star reviews of Key West reef trips mention choppy rides and shorter snorkel stops; if you get seasick easily, take medication before the trip, as the CDC advises, and sit away from the bow.
- On some days the operator decides not to go. Fury says its tours “will not depart in unsafe weather conditions” and that “every effort will be made to reschedule your tour during your stay.” Nobody publishes how often winter trips are cancelled, so plan as if it could happen to you.
The practical fix is timing. Book your snorkel trip for the first or second day of your stay, keep a later day free, and choose a listing with free cancellation. Every reef trip on our best Key West snorkeling tours page shows its policy on the listing.
Other experiences
Other Key West snorkeling trips to compare
More ways to explore the area. Each listing shows its own cancellation policy.
What to wear to snorkel in winter
The cold part of a winter trip is usually the ride back, wet and in the wind, more than the swim itself. Dress for both.
- In the water: a wetsuit in January and February, a rash guard at least from December to March. Fury says travelers visiting in January or February “may prefer to use the wetsuits we provide.” Danger Charters lists winter wetsuits on its half-day trip above, and Honest Eco lists “wetsuits during winter” on its kayak, guided snorkel and morning sail. If your listing says nothing, ask the operator or bring a thin neoprene top from home.
- On deck: a dry long-sleeve top or light jacket, a towel, and a hat. Average winter lows are in the 60s °F, and the breeze on a moving boat makes it feel cooler.
- For the sun: you still need protection in winter. NOAA recommends long sleeves, hats and a rash guard to cut the sunscreen you put in the water, and Fury requires reef-safe sunscreen without oxybenzone or octinoxate on its boats.
Fury also asks you to bring photo ID and a major credit card on most trips, and to arrive at least 30 minutes before the printed time.
Which winter trips make sense
All the usual trip types run in winter, but a few suit cool water and wind better than others.
- Shorter swims with more on deck. A dolphin-and-snorkel combination splits the trip between watching from the boat and one snorkel stop. Fury’s Dolphin Watch and Snorkel runs at 10:00 a.m. and 2:00 p.m. See our dolphin snorkel guide.
- Protected water. Danger Charters’ listings describe sailing in the calm, protected waters of the Key West National Wildlife Refuge, and its snorkeling is in that shallow backcountry, not on the offshore reef. Our comparison of catamarans and small boats covers the difference.
- A stay-dry option for anyone in your group who does not want to swim in winter water. Fury’s glass-bottom boat shows the reef through the hull; see our glass-bottom boat guide.
One thing to know before you plan around a sunset two-reef trip: Sunset Watersports’ 2 Reef Snorkel Tour and Sunset Cruise has no Viator dates until 7 March 2027, and its GetYourGuide copy first showed a bookable date of 31 January 2027 when we checked. In winter, look at Fury’s sunset snorkel trips instead.
Winter month by month
Each month has a different booking decision, and each has its own guide.
- November: the warmest of the four, with water averaging 78.3 °F and hurricane season ending on 30 November. A swimsuit and rash guard are usually enough.
- December: water averaging 75.3 °F, the start of the coolest stretch, plus Christmas and New Year dates to check on the booking calendar.
- January: the coolest water of the year at 72.5 °F and the coolest nights. Wetsuit month.
- February: 73.8 °F and the start of the warm-up, with spring break approaching in March.
If you can choose freely, our best time to snorkel in Key West guide weighs winter against spring, summer and hurricane season.
Frequently asked questions
What is Key West weather like in winter?
Mild and dry. Average highs from December to February are about 75 to 78 °F and lows about 63 to 68 °F in the NWS 1991-2020 normals, and it is the dry season, with about 2 inches of rain a month. Cold fronts bring cooler, windier spells.
How cold is the water in Key West in winter?
The harbour gauge averages 75.3 °F in December, 72.5 °F in January and 73.8 °F in February. Reef water can dip into the mid-60s °F after a front, according to Fury.
Do snorkel trips get cancelled in winter?
Some do. Operators do not leave the dock in unsafe weather, and winter is windier than summer. Fury says it tries to reschedule you during your stay. No one publishes cancellation rates, so book early in your trip and keep a spare day.
How can I check Key West snorkeling conditions today?
Look at the wind and water temperature on the National Data Buoy Center’s KYWF1 station page for Key West, check the marine forecast, and call the operator the evening before. The crew decides on the day.
Do I need a wetsuit to snorkel in Key West in winter?
Fury suggests one for January and February visitors, and Fury and Danger Charters provide them. In November and December a rash guard is usually enough unless you feel the cold.
Pick your morning or afternoon
Reef trips leave Key West most days of the year. Wind decides which reef the captain chooses, so check your date and book with free cancellation where you can.
Check dates and prices