Amazon Rainforest: What Changes in High and Low Water Season

In the central Brazilian Amazon—around Manaus, the Rio Negro, Anavilhanas National Park, and the Juma River—the year is defined by water. River levels rise and fall dramatically, flooding forests for months and then revealing beaches, trails, and dry riverbanks. For travelers, this seasonal movement changes access, activities, scenery, and how you physically move through the landscape.

👉 If you’re starting your trip in Manaus, here’s what to see and do before heading into the rainforest.

This guide breaks down what actually changes between high-water and low-water months so you can plan your lodge stay with realistic expectations.

Arial view of Ponta Negra beach in Manaus, Amazon, Brazil

Understanding the Amazon’s Seasonal Cycle

Water levels near Manaus rise and fall by many meters each year. The cycle is broadly:

• High-water season: March–August

• Low-water season: September–February

These ranges shift slightly year to year, but the rhythm holds. The result is two versions of the Amazon—both beautiful, both accessible, but experienced in very different ways.

👉 For a clear overview of how lodge itineraries change across the seasons, read our guide to how Amazon jungle lodges work.

High-Water Season (March–August)

What the Amazon Looks Like

During the rise, the Amazon becomes a world of water:

• Forests flood, creating igapó—flooded forest corridors where tree trunks stand in several meters of water.

• Many sandbanks and river beaches disappear.

• Channels widen, and boats can glide deep into the forest.

This is the classic image many people imagine: a canopy mirrored in dark water and boats weaving between trees.

How You Travel

Expect boat-heavy transfers and excursions:

• Lodges often use long boat journeys instead of road segments because channels are full and navigable.

• Small canoes become the primary way to explore flooded areas.

You spend more time on water and less on foot.

Activities That Work Best

High water is ideal for:

• Canoeing through igapó and narrow forest waterways

• Exploring seasonal channels that dry out later in the year

• River-based wildlife observation along the Rio Negro

• Pink dolphin sightings in wider channels

• Photographing the scale of the floodplain

Some dry forest hikes still run, but many trails are underwater.

Good to Know

• Afternoon showers are more common early in the season, though usually short.

• Swimming is still possible in designated lodge areas.

• This period is generally cooler on the water, thanks to constant breeze.

Low-Water Season (September–February)

What the Amazon Looks Like

As water levels fall:

• White-sand river beaches appear—especially along the Rio Negro and in the Anavilhanas region.

• Trails open up in terra firme (dry forest).

• Riverbanks reveal the height the water reached just months before.

The forest feels more grounded, with clearer walking routes.

How You Travel

Transfers shift to road + short boat combinations where channels are too shallow. Boat rides still happen daily, but routes change based on water depth.

Activities That Work Best

Low water favors:

• Longer forest hikes on dry, accessible terrain

• Beach stops

• Caiman spotting along exposed banks

• Land-based wildlife observation (tracks, feeding areas, movement patterns)

• Fishing excursions, especially in Juma and lower Rio Negro areas

There is still canoeing, but fewer flooded-forest passages.

Good to Know

• Low water means more sun exposure on beaches and open forest.

• Some channels close completely until the next flood cycle.

• Trails are longer and more stable, making this the best season for people who prefer hiking over boating.

Wildlife: Which Season Is Better?

There is no single “best” season for wildlife in the Manaus region—just different experiences:

• High water: Boats access deeper forest edges where birds and monkeys move along the flooded canopy.

• Low water:Trails and riverbanks reveal footprints, feeding marks, and roosting areas; some species concentrate around shrinking water sources.

Birdlife, dolphins, caimans, and small primates can be seen year-round.

👉To see what a lodge stay looks like deeper inside the rainforest, here’s our review of Mirante do Gavião on the Rio Negro.

How Seasons Affect Activities

Nearly all Brazilian Amazon lodges (Rio Negro, Anavilhanas, Juma, Mamori) adjust their itineraries seasonally:

High-Water Lodge Days

• More canoe trips into igapó

• Extended boat tours

• Sunset and sunrise cruises

• Limited, shorter forest trails

Low-Water Lodge Days

• More trail hiking

• Visits to river beaches for swimming and rest

• Longer land-exploration outings

• Night walks

• Some fishing activities

Your overall schedule remains full—but the mix of water vs land shifts based on the river.

Comfort, Climate and Practical Tips

Heat & Humidity

Consistently warm year-round; heat feels sharper on open sand during low water and cooler on the river during high water.

Rain

Possible anytime, but December–May generally sees more frequent showers. They’re usually intense and brief.

Mosquitoes

Levels vary more by micro-environment than month. Blackwater regions (like much of the Rio Negro) typically have fewer mosquitoes than whitewater areas.

Packing Differences

• High water:

  • Waterproof bag

  • Light layers for breezy canoe rides

  • Footwear that can handle wet landings

• Low water:

  • Sturdy walking shoes

  • Strong sun protection for river beaches

  • Water shoes for sand and river entry

    
    

If you want a bit of everything:

May–June (late rise) or September–October (early fall) often provide access to both water and land experiences.