On a September evening in La Fortuna, the clouds sit low on the flanks of the volcano, the air smells of wet earth and wood smoke, and the streets around the central park fill with children carrying paper lanterns they made at school. Cattle country, rainforest and a steaming river all meet here, and in the green season the whole landscape looks freshly washed. This is La Fortuna in the heart of the rainy season: soft light, loud frogs, quiet trails and warm water to soak in while the rain falls.
What is the weather like in La Fortuna in September?
In La Fortuna, September brings warmth, humidity, and rain most days, along with mild temperatures that barely shift from morning to night.
| Month | Average high (°F) | Average low (°F) | Rain days |
|---|---|---|---|
| August | 80.3 | 70.3 | 24.6 |
| September | 81.0 | 70.2 | 25.8 |
| October | 79.9 | 70.1 | 26.0 |
Think of it as a month of showers rather than a month of storms. Mornings are often the best part of the day, with soft light, birds active along the paths and a good chance of seeing the cone of the volcano before clouds gather around it.
Nothing is guaranteed, though, and the summit may stay wrapped in cloud for days at a time. Rain can arrive at any hour, but afternoons are the usual time for a heavy downpour.
The warmth never really lets go. Afternoons are muggy enough that a light, quick-drying shirt feels right, and nights are comfortable without a jacket, though a thin layer helps when you sit outside after a shower. Trails turn muddy, rivers run full and the waterfalls are most powerful, which is a real reward for visitors willing to get a little wet.
Days are close to evenly split between light and dark, with about twelve hours of daylight in the middle of the month. That makes an early start sensible: you get the clearest hours before the clouds build, and you are back at the hotel or in a hot spring pool when the rain begins.
What to do in La Fortuna in September
The big date of the month is Independence Day on September 15, and in La Fortuna it starts the evening before. At dusk on the 14th, children walk through town in the Desfile de Faroles, carrying paper lanterns (faroles) that glow orange, yellow and red against the wet pavement.
The next morning brings school bands, drums and flags down the main street, with families watching from the sidewalks. It is a small-town celebration, local and unhurried, and visitors are welcome to stand along the route and watch.
On the holiday, the aroma of cooking drifts through town: corn tortillas sizzling on griddles, gallo pinto (rice and beans) for breakfast, and the casado, the plate of rice, beans, plantain, salad plus a choice of meat or fish that stands as the standard lunch at little family spots called sodas. In a wet month, a hot bowl of soup or a cup of coffee from a local farm tastes especially good.
The La Fortuna Waterfall
Just beyond town, a long staircase curls down through the trees to reach the waterfall, which drops into a deep green basin. In September, after weeks of rain, the water arrives with force and the mist drifts across the lower steps. The stairs are slick, so good shoes with grip matter more than anything else you bring.
A plunge in the pool at the bottom is a big draw, yet a river running high can be swift, so look at the water before entering and follow the signs and whatever the staff on site tell you. Arrive early, while the steps are quieter and the glow is gentle. The climb back up is the real workout, so take it slowly and plan a late breakfast or a hot soak afterward.
Hot springs in the rain
If one thing fits September, it is soaking in warm river water while a shower patters on the leaves overhead. The springs around La Fortuna range from big resort complexes with swim-up bars and a dozen pools to quieter, more natural spots where the thermal water mixes with a cool stream. Rain makes the whole scene feel more private, and steam rising off the pools against the dark forest is a lovely sight in the late afternoon.
Resort-style springs suit families and anyone who wants a long evening in a more polished setting. The smaller ones suit couples and travelers who prefer a calmer, less polished experience. Both work well after a morning outdoors, when your legs are tired from stairs and trails. Bring a towel and sandals, and keep your phone in a dry bag, since the showers do not ask permission.
Hanging bridges and rainforest walks
The hanging bridges run through the forest canopy near the volcano, and September is a rich time to walk them. Everything is dripping and green, ferns and bromeliads cling to every branch, and the forest is loud with frogs, insects and birds. Mist often fills the gaps between the trees, which gives the bridges a quiet, slightly mysterious feel.
A guided walk is the best way to spot wildlife. With a trained eye, you may see sloths, toucans, monkeys or tiny frogs on leaves, though animals are always a chance and never a promise. Morning is the most active time. Wear a rain jacket and shoes that can get wet, and bring a small pack cover for your camera.
Beyond these three, the lake at the foot of the volcano is a peaceful place for a kayak or a slow boat ride when the clouds lift, and the town park, with its cathedral and its resident iguanas and sloths in the trees, is a pleasant stop at the end of a day. Chocolate and coffee farms around town offer tastings that work well on a gray afternoon, and many local restaurants serve fresh tilapia, grilled meats and tres leches cake after dark.
A two-day itinerary for La Fortuna in September
Day 1 is for the big natural sights, done early before the clouds close in. Head to the waterfall once breakfast is over, while the pool stays empty and the steps are still cool. Return to town for a late lunch at a soda, with a casado or a plate of fresh fish, then take a break at your hotel while the first afternoon rain passes.
In the late afternoon, head to a hot spring and stay through dusk. September works best in this sequence: you get your exercise during the brightest part of the day, you take your soak when rain tends to fall, and whether you eat at the springs or back in town, the day closes with no reason to be on dark roads.
Day 2 belongs to the forest and the lake. Book a morning walk on the hanging bridges, since wildlife is more active early and the light through the mist is lovely. Stop afterward for coffee and a bite at a roadside cafe, and then spend the early afternoon on the lake shore or on a farm tour with chocolate and coffee tastings, which are comfortable under a roof if the rain arrives.
When rain shows up, you have easy options: a tour of a farm, a leisurely lunch, a class in cooking or one more soak in a hot spring. If your trip falls on the evening of the 14th, finish the day in the central park for the lantern parade, then have dinner at one of the small restaurants nearby.
Is La Fortuna busy in September?
No, September is one of the quieter months in La Fortuna, with fewer tour groups and plenty of space on the trails.
The rainy season keeps many international visitors at home, so you will find more room at hot springs, shorter waits at the waterfall stairs and a calmer pace in the park and on the street. Costa Rican families do travel around Independence Day, so the days near the holiday bring more local visitors, more traffic on the roads and fuller restaurants at dinner time.
Compared with the dry months, September generally feels quieter. Still, book early if your trip includes the holiday weekend, since the best small hotels and the most popular dinner spots can fill with domestic travelers. For the quieter weeks, a booking a little closer to the trip is usually fine.
Book the activities that matter most to you first, especially if you want a morning guided walk or a particular hot spring. That is especially true if you want a specific morning slot, as the early hours are the most useful ones in a wet month. Restaurants rarely require a table far in advance, except for the larger springs complexes with set dinners.
What to pack for La Fortuna in September
Pack for warm days, wet trails and frequent showers, and keep your layers light and quick to dry.
- A light rain jacket or poncho, since showers can arrive at any hour and umbrellas are awkward on narrow trails.
- Shoes with strong grip, because the waterfall stairs and forest paths are slick after rain.
- A second pair of shoes or sandals for the hot springs and for days when the first pair stays wet.
- Quick-drying shirts and shorts, which dry far faster than cotton in humid air.
- For your phone, passport and camera, bring zip bags or a dry bag.
- Insect repellent and sunscreen, since both mosquitoes and the sun are active in the clear hours.
Good to know before you go
The U.S. State Department rates Costa Rica Level 2, ‘Exercise increased caution,’ due to crime; it says petty crime is common throughout Costa Rica and that violent crime also affects tourists, including armed robbery, homicide and sexual assault.
September is the heart of the green season, so plan your outdoor time for the morning and keep the afternoon flexible. When heavy rain falls, keep the afternoon flexible and avoid rushing from one stop to the next. Independence Day brings local celebrations and busier roads around the date, so confirm your hotel and transport early if you travel then.
Book the activities that matter most to you first, usually a guided walk or a particular hot spring, and fit the rest around them. Keep a little slack in the schedule, because a day of steady rain is a good day for a soak, a long lunch and a farm tour.
La Fortuna in September vs August and October
Going a month earlier brings a similar landscape with a touch less rain, and more of the summer vacation crowd. August has slightly more visitors and a livelier atmosphere at the springs and on the trails, while the weather is almost the same as September. It suits travelers who want a bit more company and a few more drier hours.
Going a month later puts you in the wettest stretch of the year. October brings the heaviest rain, deeper mud, higher rivers and the quietest streets, and the green is most intense. It suits travelers who want solitude, lush scenery and the lowest crowds, and who accept that some outings may be washed out. The Independence Day lanterns are a September moment and will be over by then.
If you want the lantern parade and a moderate crowd, choose September. If you need the most reliable chance of dry mornings, shift earlier. If you love empty trails and do not mind rain, shift later.
Is September a good time to visit La Fortuna?
If you don’t mind rain as part of the experience, September may be a wonderful time to visit La Fortuna, with its green scenery, quiet trails and warm water.
It will suit travelers who like soaking in hot springs, walking in cloud forest and watching waterfalls at full strength. It also suits families and couples who want a slower pace and enough room at the attractions to enjoy them. It will not suit anyone who needs a guaranteed clear view of the volcano, or who wants every day to be dry and sunny from sunrise to sunset.
On arrival, settle in and book a morning outing first, then add a hot spring evening once you know how the weather is behaving. What makes September special here is the pairing of the wet, green forest with the small-town glow of the faroles on the evening before Independence Day, when children carry their paper lanterns through the streets under the clouds.
Sources
- Open-Meteo / ECMWF ERA5, normals 1991-2020 computed for the grid cell at 10.4679N 84.6427W, checked October 8, 2026
- sunrise-sunset.org, sunrise and sunset calculated for the 15th of the month, checked October 8, 2026
- U.S. Department of State, Costa Rica Travel Advisory, issued April 1, 2026 (https://travel.state.gov/content/travel/en/traveladvisories/traveladvisories/costa-rica-travel-advisory.html), read via the State Department open data API on October 8, 2026
- U.S. Department of State, Costa Rica Travel Information, Entry and exit requirements (https://travel.state.gov/content/travel/en/international-travel/International-Travel-Country-Information-Pages/CostaRica.html), checked October 8, 2026
To plan your stay
- Things to Do in La Fortuna: Arenal Volcano, Hot Springs, the Waterfall and Day Trips
- Where to Stay in La Fortuna: Town Center, Volcano Road, Hot Springs Strip and Lake Arenal
- La Fortuna vs Monteverde: Hot Springs, Cloud Forest, Weather and Which to Choose
- Day Trips from La Fortuna: Rio Celeste, Arenal Volcano Park, Monteverde and Hot Springs