Iguazú Falls: water levels by month
Short answer: Iguazú Falls carries the most water in October (about 1,957 m³/s on the Iguazú) and the least in August (about 1,178 m³/s, 1.7 times less).
Flow depends on rain upstream in Brazil and can change within days; dams upstream also regulate it.
River flow through the year
| Month | Flow (share of peak) | Average m³/s | Level |
|---|---|---|---|
| January | 68% | 1,337 | Medium |
| February | 72% | 1,417 | Medium |
| March | 70% | 1,368 | Medium |
| April | 63% | 1,232 | Medium |
| May | 62% | 1,207 | Medium |
| June | 83% | 1,618 | High water |
| July | 72% | 1,413 | Medium |
| August | 60% | 1,178 | Medium |
| September | 70% | 1,376 | Medium |
| October | 100% | 1,957 | High water |
| November | 90% | 1,762 | High water |
| December | 75% | 1,473 | High water |
Tours
Questions
When is the best time to see Iguazú Falls?
Iguazú Falls carries the most water in October (about 1,957 m³/s on the Iguazú) and the least in August (about 1,178 m³/s, 1.7 times less). Flow depends on rain upstream in Brazil and can change within days; dams upstream also regulate it.
When is Iguazú Falls at its lowest?
August has the lowest average flow (60% of the October peak).
Average daily river discharge 2005-2024 from the GloFAS v4 hydrological reanalysis (Copernicus Emergency Management Service) via Open-Meteo, for the model river cell nearest the falls. Dams and diversions upstream can change real flow on the day.