Manaus sits in the heart of the Amazon rainforest at 3°S latitude, giving it a tropical rainforest climate (Köppen Af) with consistent heat, oppressive humidity, and heavy rainfall year-round. There are no real seasons in the traditional sense: temperatures stay between 23°C and 33°C (73-91°F) every month. What changes is the rainfall. The wettest months run from December through May, when monthly rainfall exceeds 260mm. The drier months from June through November still see rain most days, but in shorter, lighter bursts. Annual rainfall totals around 2,300mm (91 inches), making Manaus one of the wettest major cities in Brazil. The city’s weather is driven by the Intertropical Convergence Zone (ITCZ), which brings the heaviest rains when it passes overhead between March and May. Sunshine hours range from about 3.5 per day in February and March to 7 per day in August. For help deciding when to plan your trip based on this data, see the best time to visit Manaus guide.
Manaus Weather by Month: Monthly Breakdown
January
Average high: 31°C (88°F). Average low: 23°C (73°F). Rainfall: 270mm (10.6 in) over 23 rainy days. Humidity: 85%. Heavy afternoon downpours almost daily, typically between 14:00 and 17:00. About 4 hours of sunshine per day. The Rio Negro is rising and jungle trails become muddy.
February
Average high: 30°C (86°F). Average low: 23°C (73°F). Rainfall: 280mm (11 in) over 22 rainy days. Often the wettest month by accumulation. Carnival falls here some years and parades happen rain or shine. Humidity peaks at 86%. Sunshine: just 3.5 hours per day.
March
Average high: 30°C (86°F). Average low: 23°C (73°F). Rainfall: 310mm (12.2 in) over 25 rainy days. The most rain days of any month. The Amazon River reaches its highest levels, submerging forest trails. This is actually the best month for flooded forest (igapó) canoe excursions, since waterways extend deep into the jungle. Humidity: 86%. Sunshine: 3.5 hours.
April
Average high: 30°C (86°F). Average low: 23°C (73°F). Rainfall: 300mm (11.8 in) over 23 rainy days. Rain tapers slightly from the March peak. The Festival Amazonas de Opera runs at Teatro Amazonas. River levels remain at their annual maximum, ideal for boat trips through the flooded forest. Humidity: 85%. Sunshine improves to 4.5 hours.
May
Average high: 31°C (88°F). Average low: 23°C (73°F). Rainfall: 235mm (9.2 in) over 22 rainy days. A transitional month: the first half is still wet, but the second half sees more frequent dry spells. Humidity drops to 83%. River levels begin their slow descent. Sunshine: 5 hours per day.
June
Average high: 31°C (88°F). Average low: 23°C (73°F). Rainfall: 130mm (5.1 in) over 16 rainy days. The dry season establishes itself. Rain still falls regularly but in shorter, lighter bursts. Jungle trekking conditions improve as trails dry out. The Festival de Parintins happens in late June about 420km downstream. Humidity: 81%. Sunshine: 6 hours.
July
Average high: 31°C (88°F). Average low: 23°C (73°F). Rainfall: 100mm (3.9 in) over 13 rainy days. One of the two driest months. Storms are brief, 30 to 60 minutes rather than all-afternoon events. River beaches expand as water levels drop. Humidity: 79%. Sunshine: 6.5 hours. Peak month for jungle lodges and river cruises.
August
Average high: 32°C (90°F). Average low: 23°C (73°F). Rainfall: 70mm (2.8 in) over 10 rainy days. The driest month. River beaches reach their maximum size. Humidity: 77%, the lowest of the year. Sunshine peaks at 7 hours. Forest hiking trails are in their best condition all year. Things to do in Manaus include jungle treks, river beaches, and wildlife spotting.
September
Average high: 33°C (91°F). Average low: 24°C (75°F). Rainfall: 85mm (3.3 in) over 11 rainy days. The hottest month, with highs frequently touching 34-35°C (93-95°F). River beaches remain excellent. By late September, thunderstorm frequency starts increasing. Humidity: 78%. Sunshine: 6.5 hours.
October
Average high: 33°C (91°F). Average low: 24°C (75°F). Rainfall: 135mm (5.3 in) over 15 rainy days. The dry season ends. Rains increase through the month. Boi Manaus, a major cultural festival, runs in October. Humidity: 80%. Sunshine: 5.5 hours.
November
Average high: 32°C (90°F). Average low: 24°C (75°F). Rainfall: 190mm (7.5 in) over 18 rainy days. The wet season returns. Afternoon thunderstorms become daily by mid-month. Humidity: 83%. Sunshine: 4.5 hours. River levels begin their six-month rise.
December
Average high: 31°C (88°F). Average low: 23°C (73°F). Rainfall: 240mm (9.4 in) over 21 rainy days. Wet season in full swing. Christmas and New Year draw domestic tourists to Ponta Negra beach. The Reveillon fireworks at Ponta Negra are Manaus’s largest annual celebration. Humidity: 85%. Sunshine: 4 hours.
Manaus Weather by Month: Comparison Table
| Month | Avg High | Avg Low | Rainfall (mm) | Rain Days | Sun (hrs) | Humidity |
|---|---|---|---|---|---|---|
| Jan | 31°C (88°F) | 23°C (73°F) | 270 | 23 | 4 | 85% |
| Feb | 30°C (86°F) | 23°C (73°F) | 280 | 22 | 3.5 | 86% |
| Mar | 30°C (86°F) | 23°C (73°F) | 310 | 25 | 3.5 | 86% |
| Apr | 30°C (86°F) | 23°C (73°F) | 300 | 23 | 4.5 | 85% |
| May | 31°C (88°F) | 23°C (73°F) | 235 | 22 | 5 | 83% |
| Jun | 31°C (88°F) | 23°C (73°F) | 130 | 16 | 6 | 81% |
| Jul | 31°C (88°F) | 23°C (73°F) | 100 | 13 | 6.5 | 79% |
| Aug | 32°C (90°F) | 23°C (73°F) | 70 | 10 | 7 | 77% |
| Sep | 33°C (91°F) | 24°C (75°F) | 85 | 11 | 6.5 | 78% |
| Oct | 33°C (91°F) | 24°C (75°F) | 135 | 15 | 5.5 | 80% |
| Nov | 32°C (90°F) | 24°C (75°F) | 190 | 18 | 4.5 | 83% |
| Dec | 31°C (88°F) | 23°C (73°F) | 240 | 21 | 4 | 85% |
