Dry air mass advances through Brazil’s interior, drops humidity to critical levels, and prolongs period of heat and atmospheric stability in Central-West and Southeast regions, with direct impacts on health and maintenance of typical pattern for dry season transition.
The influence of a dry air mass intensifies over Brazil, maintaining stable weather across much of the Central-West and Southeast, with a sharp drop in relative humidity levels, which are already reaching alert levels in several regions.
This scenario has been observed mainly during afternoons, a period when the combination of heat and absence of clouds favors a more significant reduction in humidity, increasing thermal discomfort and health impacts.
Atmospheric block maintains dry weather and high heat
According to the National Institute of Meteorology, relative humidity levels are already below 30% in several areas, a threshold considered an alert by climate monitoring and public health agencies.
-
Aquifers plummeting, carbon sinks saturating, and dengue advancing to new latitudes: a report with 70 researchers and over 150 specialists warns that climate and biodiversity have entered a cycle of mutual destruction that threatens energy, water, health, and work on a global scale.
-
The Planetary Health Check confirmed what scientists feared: the window to reverse the seven overshot planetary systems is five years before it closes, and none of them are improving, while the models that were supposed to predict what comes next admit that they never simulated a planet in this state.
-
Cuba is without fuel, without energy, and without a way out, but a 21-year-old young man set up a homemade solar panel factory that has already equipped more than 15 electric tricycles, increased the vehicles’ range, and is saving the livelihood of workers who no longer had a way to get around the island’s streets.
-
Few remember, but the 2024 drought in the Amazon already affects transport, energy, and agriculture. Rivers are reaching critical levels, smoke covers cities, and the scenario triggers a global alert about climate change.
This behavior is a direct consequence of the action of a high-pressure atmospheric system, which acts as a block and hinders the advance of cold fronts through the country’s interior, maintaining the stability pattern.
As a result, there is less cloud formation and a significant reduction in rainfall, which prolongs periods of dry weather, clear skies, and high temperatures, especially in the afternoon.
Southeast interior registers humidity below 25%
In the Southeast, dry weather predominates mainly in the interior of the states, where maritime influence is lower and dry air circulation remains more intense throughout the days.
In these areas, relative humidity levels frequently fall below 30%, with specific readings that can reach values close to or even below 25%, considered critical by specialists.
The persistence of this pattern reinforces a typical characteristic of the second half of autumn, when central Brazil begins the gradual transition to the dry season, marked by scarce rainfall and greater daily thermal amplitude.
Low humidity affects health and requires care
The reduction in air humidity has direct effects on the population, especially in more sensitive groups, such as children and the elderly, who tend to suffer from symptoms related to the drying of respiratory tracts.
According to guidelines from the World Health Organization and Civil Defense agencies, levels below 30% already require care, while indices near 20% enter a more severe alert state.
Among the main effects associated with dry weather are irritation in the eyes, nose, and throat, an increase in respiratory problems, and a higher risk of dehydration, especially during prolonged periods of heat exposure.
Forecast indicates continued stable weather
The forecast indicates the maintenance of this climatic pattern in the coming days, with a predominance of sun, heat, and low humidity levels across much of the Central-West and in the interior of the Southeast.
Nevertheless, some specific areas may show punctual changes, such as southern Mato Grosso do Sul and coastal regions, where the passage of cold fronts can cause increased cloudiness and isolated rainfall.
A broader alteration of this scenario depends on the weakening of the high-pressure system acting as a block, allowing the entry of more organized meteorological systems into the country’s interior.
As long as this pattern does not change, the trend is for continued dry and hot weather, including during the holiday and throughout next week, keeping humidity levels at alert thresholds in several regions.

Be the first to react!