Manuel Antonio in the Rainy Season (Green Season): Honest Guide to May to November

⭐ Best green season windows: July and November. July sits at about 15 rain days thanks to the mid-season veranillo, and November eases back to about 15 as the season turns. Both carry the green season upside, low crowds and low rates, without the full weight of the September and October wet stretch.

The green season is the version of Manuel Antonio most planning quietly steers you away from, and in our view that is a mistake for a large group of visitors. This is when the rainforest above the beach actually looks like rainforest: dense, dripping, loud with birds, and largely free of the queue that forms at the park gate between Christmas and Easter. The sea does not cool down, the wildlife does not leave, and the difference in what you pay is substantial.

We'd book this if value, wildlife, whales or surf drive your trip and you can accept losing most afternoons to rain. The tradeoff is not subtle. September and October are genuinely wet, park trails are muddy and slick on the steeper sections, and a few small businesses shut for the quietest weeks. Our national park tour guide and things to do guide cover what the season does best, and our rainy vs dry season comparison puts the two halves of the year side by side.

Calling May to November one season flattens some very real differences. The wet half of the year has a shape: an abrupt start in May, a build through June, a mid-July pause, a September and October peak, and a clear improvement through November.

The mid-July veranillo

One quirk is worth planning around. Mid-July brings the veranillo, the "little summer", a short drier spell that interrupts the wet season pattern. It is not a guarantee, but it is why July averages about 15 rain days rather than the 18 to 22 of the months around it. Add the first humpbacks of the southern migration and July becomes the strongest all-round month of the green season. Our July guide covers how that plays out in practice.

The September and October floor

These are the wettest months in Manuel Antonio at roughly 21 and 22 rain days, and also the cheapest and emptiest. Rooms are at their lowest of the year, the park trails can feel close to private, and some restaurants and smaller operators take their annual closure. Whales are still offshore through much of this window. What typically happens is that travellers who arrive expecting wet afternoons enjoy these weeks enormously, while travellers expecting beach days from breakfast to sunset do not. Our October guide covers the wettest month in detail, and the September guide the quietest.

Temperature and Humidity

Nothing much happens to the thermometer. Green season highs run 30 to 32°C (86 to 90°F) and nights sit at about 23°C (73°F), which is within a degree or two of February. What changes is how it feels: humidity is high, the air is heavy after a shower, and clothes take a long time to dry. Pack quick-dry fabrics rather than cotton and you remove most of the discomfort. UV stays very high through cloud, so sunscreen is not optional just because the sky is grey.

Rain Pattern

The typical green season day is not a washout. Mornings frequently start bright or lightly overcast, cloud builds through late morning, and showers arrive in the afternoon, sometimes as a heavy multi-hour downpour with thunder. September and October break this pattern more often, with rain that starts earlier and lingers. Our take: treat mornings as your working hours and put anything weather-dependent, including the national park, before noon every single day.

The Sea, the Surf and the Beaches

This is the part that surprises people. The Pacific here sits at 28 to 29°C (82 to 84°F) every month of the year, so swimming at Playa Espadilla and the sheltered Playa Manuel Antonio inside the park is comfortable in the green season exactly as it is in the dry one. Swell is bigger and more consistent in these months, which is a plus for surf lessons and a minor caution for weak swimmers, since rip currents strengthen with the larger sets. Heavy rain can also push river runoff along the coast for a day or two, which clouds the water and takes the shine off snorkelling.

Rain day counts are abstract. What those numbers translate to on a real itinerary is far more useful, so here it is.

• You lose afternoons, not days. The standard pattern is a workable morning followed by showers from early afternoon. A trip built around 7 AM starts loses very little; a trip built around lazy 11 AM departures loses a lot.
• The park is best first thing anyway. Wildlife is most active in the early morning, which happens to be the driest part of a green season day, so the right plan for the weather is also the right plan for the animals.
• Trails get muddy and slick. The main park circuits are well maintained, but the steeper connectors and the Cathedral Point loop hold water. Closed shoes with grip make a real difference.
• Boat trips are morning trips. Whale watching, sailing and the mangroves all read better before the wind and rain build.
• Surf gets bigger. Good news for lessons and for watching, worth respecting if you swim.
• Roads and drives take longer. Sustained rain slows the coastal route and the inland run toward Nauyaca and the Savegre, so build slack into long day trips.
• Cancellations are rare but possible. Most tours run in rain. Rafting and offshore boat trips are the two most likely to be adjusted for safety after a heavy spell.
• Some places are shut. A handful of restaurants and smaller operators close for a few weeks in September or October. Check before you build an evening around one specific place.

The travellers who struggle in the green season are the ones running a fixed, back-to-back schedule. Leave one flexible day and the season stops feeling like a gamble.

The most useful thing to understand about Manuel Antonio's climate is that temperature barely moves all year, while the number of wet days swings sevenfold. Daytime highs sit between 30 and 33°C every month, nights hold around 23°C, and the sea stays at 28 to 29°C. What actually changes your trip is how many days see rain, and when.

Full Month-by-Month Figures

What the Numbers Actually Mean

Three things stand out. First, February and March are the driest months by a wide margin at roughly three rain days each, which is why the dry season peaks then rather than in December. Second, October is the wettest at around 22 rain days, with September just behind. Third, the transition is abrupt rather than gradual: April jumps from about 6 rain days to 17 in May, so the season flips within weeks rather than easing in.

The temperature column is almost a flat line, and that is the point. Most people don't realize that choosing when to visit Manuel Antonio is a decision about rain, humidity and crowds, not about heat. The sea is swimmable at 28 to 29°C every month of the year.

ℹ️ Figures are typical monthly averages drawn from our month-by-month Manuel Antonio guides and are indicative rather than exact. Conditions vary year to year, so treat these as the shape of the year rather than a forecast.

The green season is genuinely excellent for some travellers and genuinely wrong for others. Being honest about which group you fall into is the most useful thing this guide can do for you.

Come in the green season if you are

• Budget-conscious. Rooms and tours are at their lowest of the year, with September and October the cheapest weeks of all.
• Wildlife-focused. The park is lush and quiet, birdlife is loud, and night tours are at their yearly best.
• Here for whales. Humpbacks are offshore roughly July to October, squarely inside the green season.
• A surfer or learning to surf. Swell is bigger and more consistent than in the dry months.
• Crowd-averse. September and October are the emptiest weeks on the central Pacific by a clear margin.
• Flexible. If you can shuffle an activity by a day when the forecast turns, the season costs you almost nothing.

Choose the dry season instead if you are

• Here for full beach days. This is the decisive one. If your picture of the trip is sunrise-to-sunset on the sand, May to November will frustrate you and December to April will not.
• Set on clear-water snorkelling. Runoff after heavy rain repeatedly clouds visibility.
• On a short, fixed itinerary. Two or three days with no slack and a packed plan is exactly where wet afternoons hurt.
• Travelling with small children or anyone unsteady. Slick trail sections and constant mud make the dry months considerably easier.
• Set on a specific restaurant or small operator. Some close for a few weeks in September and October.

We think the tradeoff is a straightforward one: you swap guaranteed afternoons for lower prices, a greener forest and far fewer people. Our rainy vs dry season comparison and our best time to visit guide work through it in more detail if you are still deciding.

Green season packing is not about staying dry, which is unrealistic on a humid Pacific coast. It is about drying out fast and keeping your footing.

• A light rain jacket or poncho, not an umbrella. Packable and hooded beats anything you have to hold on a trail.
• Closed shoes with real grip. The single highest-impact item. Trail runners or light hiking shoes beat smooth soles on wet park trails.
• A second pair of shoes. Nothing dries overnight in this humidity, so you want dry footwear for the next morning.
• Quick-dry clothing only. Synthetic or merino. Cotton stays wet for days here.
• Dry bags or zip-lock bags. For phone, camera and passport; day packs are rarely as waterproof as they claim.
• Reef-safe sunscreen. UV stays very high through cloud this close to the equator.
• Insect repellent. Mosquito activity is noticeably higher in the wet months.
• Swimwear you will actually use. The sea is 28 to 29°C every month, so morning swims are on regardless.
• Binoculars. Cheap ones transform the park and the mangroves, especially when the light is flat.

• Book park entrance ahead. Manuel Antonio National Park caps daily visitors year-round, so tickets should be secured in advance rather than bought at the gate.
• Treat mornings as your only reliable hours. Cloud builds through late morning and showers usually arrive after midday.
• Keep one flexible day. A single unplanned day turns a washed-out afternoon into a rescheduled activity rather than a lost one.
• Pick July or November if you can choose. Both sit at about 15 rain days and carry the green season upside with meaningfully less rain than June, August, September or October.
• Time it for whales. Humpbacks are offshore roughly July to October, which pairs neatly with the veranillo in July.
• Do not build the trip around uninterrupted beach days. Swim in the morning, treat afternoon sun as a bonus.
• Book sheltered activities as backups, not fillers. Chocolate tours, cooking classes and the mangroves are the ones that work whatever the sky does.
• Grip matters more than waterproofing. The steeper park connectors and the Cathedral Point loop are slick all season.
• Book less far ahead, and ask about rates. Availability is wide open in September and October, which is why they are the cheapest weeks of the year. Our hotels guide covers where to stay.
• Check for closures. Some restaurants and smaller operators take their annual break in the wettest weeks.
• Planning around a specific month? Our May, June, August and November guides cover the rest of the season.