Dry Tortugas National Park sits about 70 miles west of Key West in the Gulf of Mexico. Its remote spot leads to some pretty unique weather patterns that really shape what visitors experience.
The park’s subtropical climate splits into two main seasons, and the differences between them can be dramatic. One week you might get flat, crystal-clear water perfect for snorkeling, and a few days later, rough seas and poor visibility can take over.
Winter brings strong cold fronts and wind, while summer lines up with hurricane season but often gives you ideal marine conditions. Weather affects everything here—ferry schedules, camping, snorkeling, even bird watching.
Because the park sits exposed in the open Gulf, even small weather systems can cause outsized impacts. That’s why keeping an eye on the forecast is so important if you’re planning a trip.
Overview of Climate in Dry Tortugas National Park
The park has a subtropical maritime climate, with warm temps from 65°F to 89°F all year. Wet and dry seasons are pretty distinct.
Dry Tortugas’ remote spot, 70 miles from Key West, means the weather’s influenced by the ocean and Caribbean currents more than anything on land.
Geographical Context and Location
Dry Tortugas National Park sits out in the Gulf of Mexico, about 70 miles west of Key West, Florida. It’s about as far south as you can get in the continental U.S.
The park is made up of seven little islands, all surrounded by warm ocean water. That water really drives the climate here.
Key geographical factors include:
- Latitude: about 24.6°N
- Surrounded by Gulf of Mexico waters
- Close to Caribbean currents
- Far from larger landmasses
Warm currents flow from the Caribbean, through the Gulf, and into the Atlantic, giving the park a microclimate that’s different from mainland Florida.
During summer, continental weather doesn’t really reach this far south. In winter, cold fronts sometimes drop down, bringing cooler temps and wind.
Tropical Climate Classification
Dry Tortugas falls into the subtropical maritime climate category. That means warm temps most of the year and not a lot of seasonal change compared to places farther north.
Temperature rundown:
- Summer highs: Up to 90°F (32°C)
- Winter lows: Around 65°F (18°C)
- Annual average: 83°F (28°C)
There are two main seasons. The wet season goes from mid-May through November and brings about 75% of the yearly 40 inches of rain.
The dry season runs from November through mid-May. Temps usually sit in the low 60s to mid-70s. Sometimes, cold fronts bring in cooler, drier air.
Humidity stays high all year thanks to the ocean. The heat index often feels hotter than the actual temperature.
Comparison with Broader Florida Climate
Dry Tortugas has steadier temps than the Florida mainland because the ocean moderates things. Northern Florida swings more between hot and cold, but the park stays pretty warm.
The park gets less rain than most of Florida—about 40 inches a year, making it one of the state’s driest spots.
Compared to mainland Florida:
- Temps are more stable
- Less rain overall
- Windier, thanks to ocean exposure
- More hurricane risk since it’s right in the storm zone
Mainland weather systems don’t reach the park as often as they do farther north. Summer storms pop up from local heat and moisture, not big weather fronts.
Winter gets windier and the seas rougher than on the mainland. Open water all around means choppier conditions, especially in the dry season.
Seasonal Weather Patterns
The park’s two main seasons shape everything for visitors. It shifts from a cooler, windier dry season to a hot, humid wet season with plenty of storms.
Dry Season Characteristics
The dry season goes from November to mid-May. Temps usually land between the low 60s and mid-70s.
Wind and Sea Conditions
Winter means more wind. That breeze kicks up rougher seas around the islands, so boaters should expect choppier water.
Temperature Patterns
Cold fronts sometimes sweep through in winter, bringing cooler air. Wind chill can make it feel colder than the thermometer says.
Precipitation Levels
Only about 25% of the annual rain falls during the dry season. When it does rain, it’s usually quick squalls that don’t last long.
Wet Season Characteristics
The wet season runs from mid-May through November. Temps climb into the upper 80s and low 90s, and humidity goes way up.
Heat and Humidity
The heat index can run 10-15 degrees hotter than the air temp. When it’s 90°F and humid, it might feel like 105°F. Sweating doesn’t cool you off as much in this kind of weather.
Thunderstorm Activity
Thunderstorms pop up almost daily in summer. Some last just a few minutes, others stick around for hours and can dump a lot of rain.
Hurricane Risk
Dry Tortugas sits in one of the most hurricane-prone spots in the country. Atlantic hurricane season is June 1 through November 30. The park sometimes closes before, during, or after big storms.
Transitions Between Seasons
Spring and fall bring gradual changes between the two main seasons. These are usually the nicest times to visit.
Spring Transition
April and May usually have the best weather—moderate temps and lower humidity. Storms start to pick up as summer approaches.
Fall Transition
October and November see less rain and fewer storms. Hurricane season is still going, but the risk drops off toward late fall. Temps start to cool, but it’s a slow shift.
Monthly Weather Variations
Weather shifts through the year, with winter lows in the mid-60s and summer highs over 90°F. The park averages about 36 inches of rain, and skies tend to be clearer from October to May.
Temperature Ranges by Month
Winter is the coolest stretch. January is coldest, with lows around 64°F and highs up to 74°F. February warms up a bit, from 64°F to 75°F.
Spring brings steady warming. March runs 67°F to 78°F. April gets warmer, 70°F to 81°F. May kicks off the hot season, 74°F to 86°F.
Summer is the hottest. June goes from 77°F to 90°F. July stays hot, 78°F to 91°F. August is peak heat—78°F to 92°F.
Fall cools off slowly. September is still hot, 77°F to 90°F. October cools to 75°F to 85°F. November drops to 71°F to 79°F. December rounds it out at 66°F to 76°F.
Rainfall and Humidity Patterns
The park gets about 36.4 inches of rain over 88 days each year. Summer has the most rain, around 3.6 inches a month.
Summer rain mostly comes from quick, heavy afternoon storms. They blow in fast and clear out just as quickly. Humidity stays high, making everything feel even warmer.
Winter and spring are drier. The clearer season is from late October through May, so you get more predictable weather. Rain is lighter and less frequent.
Humidity never really drops, thanks to the ocean. In summer, the combo of heat and humidity can feel overwhelming.
Average Daily Sunshine
Clear skies are most common from October through May. That’s the best stretch for sunshine and outdoor plans.
Clouds build up more in the summer. Even with more rain, you’ll still get sunny breaks between storms. Mornings tend to be clearest; clouds roll in by afternoon.
Daylight hours change with the seasons. Winter days are shorter but sunnier. Summer brings long days, but clouds and storms can pop up anytime.
Weather can shift fast out here. Always check the latest forecast, since marine conditions matter more than what’s going on back on the mainland.
Extreme Weather Events
Dry Tortugas faces two main types of severe weather: hurricanes and summer thunderstorms. Both can mess with your plans or even close the park.
Hurricanes and Tropical Storms
The park’s location, 70 miles west of Key West, puts it right in the path of hurricanes. Hurricane season runs June 1 to November 30.
Hurricanes form over warm water and get stronger as they move through the Caribbean and Gulf. The park’s remoteness makes it especially vulnerable.
Storm breakdown:
- Tropical Depression: Winds up to 38 mph
- Tropical Storm: 39-73 mph
- Hurricane: 74+ mph
- Major Hurricane: 111+ mph (Category 3-5)
The park might close before, during, or after big storms. You can check conditions at 305-242-7700 before heading out.
Strong hurricanes bring storm surge, flooding, and dangerous seas. The islands don’t offer much shelter from hurricane winds.
Thunderstorms and Wind Events
In summer, thunderstorms hit almost daily from mid-May through November. Warm, humid air and unstable skies set the stage.
Storms can be quick or drag on for hours. Some dump several inches of rain in no time.
Winter brings its own issues—stronger winds and rougher seas. Cold fronts from the mainland make boat travel tough.
Waves and chop pick up in winter, sometimes making snorkeling or diving tricky, even if the sun’s out.
Lightning is a real danger during summer storms. If you hear thunder, it’s best to get inside.
How Weather Affects Park Activities
Weather shapes everything at Dry Tortugas, from ferry rides to snorkeling. Being so far from Key West, the park’s especially exposed to tropical systems and rough seas.
Best Times for Visiting and Outdoor Activities
April and May usually give you the best shot at good weather. Temps run from the low to mid-80s, and humidity isn’t as bad as in summer.
Winter (December-March) brings comfortable temps—65-76°F. But cold fronts can make things windy and the seas rough. Ferry rides get bumpy, and water sports aren’t always easy.
Summer (June-November) is hot and humid, with temps up to 88-90°F. The heat index often tops 105°F because of high humidity. Thunderstorms are frequent but usually don’t last long.
Most rain falls from mid-May to November. August and September are the wettest months and line up with peak hurricane season.
Best times for activities:
- Snorkeling/Diving: Best visibility in calmer winter months, though the water’s cooler
- Birdwatching: Spring migration (April-May) is excellent
- Fort Jefferson Tours: Good year-round, but in summer, go early to beat the heat
Weather-Related Travel Tips
Ferry services to Dry Tortugas rely on sea conditions and weather forecasts. Winter often brings rough seas that can lead to trip cancellations or bumpy rides.
Check the offshore weather forecast before you head out. The National Weather Service shares marine forecasts just for the Dry Tortugas area.
If winds climb above 25 knots, expect ferry service to get suspended. It happens more often than you’d think.
Packing Essentials by Season:
- Summer: Lightweight, breathable clothes, rain gear, and extra sunscreen
- Winter: Light jacket, windbreaker, and layers for those weird temperature swings
Seaplane flights deal with the same weather headaches. Thunderstorms or high winds can keep planes grounded.
If there’s a tropical storm warning or hurricane watch, park access might be off-limits. Once winds hit 39 mph, the park usually shuts down.
Camping out there? You’ll need to prep for the weather. Summer storms can bring lightning, and winter cold fronts sneak in with chilly temps and strong winds.
Safety Considerations and Preparedness
Heat-related illness is the big weather risk in summer. High temperatures and humidity crank up the heat index fast.
Keep an eye on the heat index—it tells you how hot it actually feels, not just what the thermometer says. When it’s 90°F and humid, that number can jump to 105°F or higher.
Heat Safety Measures:
- Do outdoor stuff early, before it gets brutal
- Find shade at midday when the sun’s relentless
- Drink water often, even if you don’t feel thirsty
- Watch for heat exhaustion: dizziness, nausea, rapid heartbeat
Summer thunderstorms bring lightning—seriously dangerous stuff. Fort Jefferson’s metal structures attract strikes, so get inside if a storm rolls in.
Hurricane season? It gets intense. The park sits in a hurricane hotspot, so have an evacuation plan and check weather updates often.
Emergency Weather Resources:
- Park contact: 305-242-7700 for up-to-date info
- National Weather Service marine forecasts
- NOAA Weather Radio for ongoing updates
Strong currents and rough seas add extra risks. Winter cold fronts can whip up bigger waves and make swimming dangerous around the islands.
Accessing Weather Forecasts for Dry Tortugas National Park
Getting reliable weather info is a must out here. The park sits 70 miles west of Key West, so it’s not like you can just pop back if things change.
The National Weather Service gives the most accurate forecasts. Plenty of online platforms help you plan your trip, but some are better than others.
Where to Find Current Weather Updates
The National Weather Service is your go-to for official Dry Tortugas forecasts. Their marine updates matter most since you have to take a boat or seaplane to get out there.
AccuWeather offers long-range forecasts, up to 90 days out. They break down daily highs, lows, and rain chances just for the park.
Check the park’s official site at nps.gov/drto for current conditions and any weather-related closures. Staff update it regularly during storms.
Weather.com and other big weather sites use data from Key West Airport. It’s about 70 miles east, but it’s the closest solid weather station.
If you’re boating, tune into marine weather radio on VHF channels for real-time updates. They’ll cover wind, waves, and visibility—stuff you really need to know.
Interpreting Forecasts for Trip Planning
Heat index readings really matter in the summer, especially when temperatures hit 90°F and humidity climbs. Don’t just check the air temperature—keep an eye on that heat index before heading out.
Wind forecasts can make or break a boat trip to the park. When winds stay above 15-20 mph, smaller boats can face rough seas and a pretty bumpy ride.
Thunderstorm probability jumps from May through November, which is the wet season around here. Storms pop up fast and sometimes stick around for hours.
Extended forecasts give you a shot at picking the best travel dates. The 10-14 day outlook shows general trends, but honestly, details after five days get fuzzy.
Hurricane season stretches from June through November, so you’ll want to keep an eye on tropical weather. Severe storms can shut the park down completely, so it’s smart to keep your plans flexible.