Manaus dawned this Friday (9) once again covered in smoke. Civil Defense sent out an alert on cell phones asking that no one leave home without a mask, municipal schools closed and the city hall placed the city on alert. The capital's gray sky is the most visible face of a crisis that is spreading across the state: in September, Amazonas recorded 3,726 hot spots, almost four times the 942 in the same month of 2025.
The jump came after a quarter in which the rain almost disappeared. From July to September, Manaus accumulated 44 millimeters, a tiny amount close to the 202 millimeters expected for the period, according to data from the National Institute of Meteorology (Inmet). August ended with no recorded rain, when the average for the month was 56 mm.
The air that residents breathe shows the size of the problem. This Friday, Manaus recorded the worst air quality in the country, full of particles released by the fires. Within the city itself, firefighters needed a plane to contain a fire that had been going on for 48 hours.
According to researcher Luiz Aragão, from the National Institute for Space Research (Inpe), the origin of the fire follows a known pattern at this time of year: fires to renew pastures and clear areas that were already open.
What changes in 2026 is the scenario in which these flames are lit. With the forest parched due to lack of rain and El Niño, the fire escapes control and advances through the forest.
The ban on the use of fire throughout the state was only decreed by the government of Amazonas on September 9, when August had already closed with 2,231 fires, up from 1,842 the previous year. The Public Ministry of Accounts of Amazonas (MPC-AM) requested an investigation to determine whether the state government's actions against burning, forest fires and pollution episodes were effective.
October is the end of the dry season in the Amazon and, with it, the height of the fire season. It is at this time, before the arrival of the rains, that producers use fire to renew pastures, eliminate weeds and clear vegetation that grows back in already open areas.
This type of burning can be authorized by environmental agencies, with area limits. However, with the vegetation dry, the flames reach proportions that are beyond control.
According to Luiz Aragão, a researcher at Inpe, the index is slightly above the historical average and below that recorded in 2024, the year in which smoke from the Amazon reached the Southeast.
Today, the worst states in the ranking of hot spots are: Pará, Mato Grosso, Tocantins, Bahia and Amazonas.
What makes the situation in Amazonas worse is the context in which this fire occurs: a dry forest, with no rain in sight, with fires very close to a capital.
Between January and June, Deter, Inpe's alert system, identified 1,295 km² of areas under alert for loss of native vegetation in the Amazon. It is the lowest level for the period since the beginning of the historical series, in 2016.
What Aragão explains is that most of the outbreaks are not in areas targeted for deforestation, but in pastures and areas that have already been deforested, often on the edge of the forest. With the vegetation dry, the fire takes on large proportions and becomes difficult to control.
With the intensification of El Niño, these ignition sources that are burning in the pasture areas, in the secondary forests, tend to enter the forests, which are in a much drier condition due to the lack of rain. The sum of these factors is what generates this increase in fires and all this smoke that directly affects the population and their health, explains Aragão.
According to analysis by the National Center for Natural Disaster Monitoring and Alerts (Cemaden), humidity is low in the Amazon region, with several stretches under severe and moderate drought. This is related to the arrival of El Niño, an abnormal warming of the waters of the Pacific Ocean, which reduces rainfall in the north of the country.
The last rain in the capital fell on October 3, and no new precipitation is expected. Each day without water leaves leaves, branches and grass drier, and it is this material that feeds the fire and makes it spread. The lack of rain also prevents the smoke from dispersing and reduces the impact on the region.
The atmosphere depends on two great cleaners: rain and wind. Under El Niño, drought prevails, and these two cleaners practically go on strike. The result is a greater concentration of smoke from the fires. Excessive heat favors the spread of the fire, which becomes more out of control, and this is added to the lack of rain, which could reduce the smoke, explains meteorologist César Soares, from Climatempo.
In 2024, when large fires advanced over the Amazon, the smoke traveled for kilometers and even covered the sky of São Paulo. According to the meteorologist, this time it shouldn't go that far, due to the movements of the atmosphere. Still, it is possible that it will reach neighboring states, such as Rondônia and Mato Grosso.
