Spring time in Marathon, Florida
Spring is one of the most refreshing and enjoyable times to visit Marathon in the Florida Keys. With warm breezes, rising water temperatures, and fewer crowds than the winter season, it’s the perfect window for travelers who want sunshine, outdoor adventure, and that signature laid-back island vibe.
Here’s everything you need to know about visiting Marathon in the spring — from average seasonal temps to top activities, events, and FAQs.
Average Spring Temps
& Climate
March: High 79°F / Low 69°F
April: High 83°F / Low 72°F
May: High 87°F / Low 76°F
Humidity Index
Generally 73–75%, which is much more comfortable than late summer
Rainfall
Light to moderate spring showers
Average of 2–3.3 inches of rain per month
May sees a slight uptick as the Keys approach the wet season
Water Temperatures
March: ~74°F
April: ~78°F
May: ~80–81°F
These warming water temps make spring an excellent time for snorkeling, swimming, boating, or simply relaxing seaside with your toes in the sand.
Top Things to Do in Marathon During the Spring
Snorkeling & Diving
Reefs come alive with colorful fish, turtles, and crystal-clear visibility. It’s the ideal season for exploring Sombrero Reef, Coffins Patch, or taking a guided dive trip.
Fishing (Offshore & Inshore)
Spring is prime time for sailfish, mahi-mahi, snapper, tarpon, and more. Whether you're hopping on a charter or casting from shore, fishing conditions are excellent.
Kayaking, Paddleboarding & Boating
Mild winds and gentle currents make April and May fantastic months to rent a kayak, join a mangrove paddle tour, or enjoy a sunset boat cruise.
Spring Seasonal Events
Marathon Seafood Festival
(March)
Seven Mile Bridge Run
(April)
Islamorada Island Fest
(April)
Mother's Day Dolphin Tournament
(May)
Is Spring a Good Time to Swim in Marathon?
Absolutely. Water temps warm from the mid-70s to low-80s by May, making swimming and snorkeling very comfortable.
Are There Fewer Crowds in Spring?
Yes. After the winter rush, spring becomes more peaceful and affordable, with easier reservations for charters, rentals, and activities.
Does It Rain A Lot in Spring?
Spring brings light rain — mostly quick showers. May starts to see slightly more rain, but it’s still far from the heavy summer wet season.