Worst air pollution São Cristóvão, today and tomorrow
Today (20 September): Air quality in São Cristóvão is moderate. AQI and PM2.5 are moderate; PM10 is fair; NO2, O3, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 4:00 AM (PM2.5: 40.6/100).
Tomorrow (21 September 2026): Air quality in São Cristóvão is fair. AQI improves to fair; PM2.5 decreases to fair; all other pollutants stay as today. Pollution peaks around 10:00 AM (PM2.5: 24.0/100). Airmine updates local air quality forecasts four times daily.
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Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team
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São Cristóvão's air quality reflects the greater Aracaju metropolitan area in Sergipe, with vehicle emissions from the BR-101 and surrounding mixed industrial, historical, and residential character contributing local sources in this UNESCO heritage city. Atlantic trade winds from the Sergipe coast provide background maritime ventilation, while the growing metropolitan expansion drives increasing vehicle emissions throughout the year.
Today - 20 September | Pollution peaks at 04:00
AQI:
Moderate
40.6/100
PM2.5 (fine particles):
Moderate
40.6/100
PM10 (coarse particles):
Fair
33.3/100
NO2 (nitrogen dioxide):
Good
0.1/100
O3 (ozone):
Good
10.9/100
SO2 (sulfur dioxide):
Good
0.3/100
CO (carbon monoxide):
Good
0.3/100
HCHO (formaldehyde):
Good
0.5/100
PM1 (ultrafine particles):
Good
19.5/100
Levels show the poorest local air quality during the day
Tomorrow - 21 September | Pollution peaks at 10:00
AQI:
Fair
24.0/100
PM2.5 (fine particles):
Fair
24.0/100
PM10 (coarse particles):
Fair
22.4/100
NO2 (nitrogen dioxide):
Good
0.2/100
O3 (ozone):
Good
11.2/100
SO2 (sulfur dioxide):
Good
0.3/100
CO (carbon monoxide):
Good
0.3/100
HCHO (formaldehyde):
Good
0.6/100
PM1 (ultrafine particles):
Good
11.1/100
Pollen forecast in São Cristóvão
View pollen forecastFrequently Asked Questions
Is air quality bad in São Cristóvão right now?
On 20 September 2026, overall air quality in São Cristóvão is moderate. AQI is the main air quality indicator at 40.6/100. Pollution peaks around 4:00 AM (PM2.5: 40.6/100).
Will air quality be worse tomorrow in São Cristóvão?
On 21 September 2026, air quality conditions in São Cristóvão will be better than today, with AQI forecast at fair at 24.0/100. Pollution peaks around 10:00 AM (PM2.5: 24.0/100).
When is air pollution at its worst in São Cristóvão?
In São Cristóvão, reduced air quality is most noticeable when native Atlantic Forest remnants and introduced urban trees pollen peaks, and on days affected by vehicle emissions from the BR-101 and surrounding mixed industrial, historical, and residential character; things typically settle down again once the weather pattern shifts.
Are air quality levels in São Cristóvão based on measurements or forecasts?
It is forecasts derived by downscaling forecasts provided by EU’s Copernicus Atmosphere Monitoring Service (CAMS) by taking into account local conditions such as traffic patterns. CAMS bases its forecast on satellite measurements of particles and chemical compounds in the atmosphere. Airmine’s services were developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team.
Why doesn’t the forecast always reflect wildfire impacts?
Airmine’s forecast uses CAMS (Copernicus Atmosphere Monitoring Service) as its background atmospheric model. While CAMS includes wildfire emissions, these are derived from satellite observations and are not available in real time. During rapidly evolving wildfire events, there may therefore be a delay before increased emissions are incorporated into the model. As a result, the forecast may temporarily underestimate PM₂.₅ and other pollutants associated with wildfire smoke.
During rapidly evolving wildfire events, CAMS may lag by approximately 1–2 days before increased wildfire emissions are fully represented, which can lead to temporary underestimation of PM₂.₅ concentrations in Airmine’s forecast.
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Data provided by Airmine — Last update: 20 September 2026 at 14:33 CEST (Data is updated four times daily.)
This forecast is produced independently using Airmine's own atmospheric data and models.
Unless explicitly made clear, the content on this site has not been paid for by external organisations and is Airmine's sole responsibility.
Disclaimer: Forecasts are provided for informational purposes only and should not be relied upon as medical advice. Actual pollen and air quality conditions may vary from the forecast. If you have allergies, asthma, or another medical condition, consult a healthcare professional. Please see our Terms of Service for important information about limitations of liability.
Some text on this page may be generated or summarised using artificial intelligence (AI). Wherever possible, AI-generated content is enriched with Airmine's proprietary data to improve its accuracy and relevance. However, AI-generated content may still contain errors, omissions, or inaccuracies.
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