Worst air pollution Castanhal, today and tomorrow

Today (16 July): Air quality in Castanhal is fair. AQI, PM2.5, and O3 are fair; PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 3:00 AM (O3: 26.1/100).
Tomorrow (17 July 2026): Air quality in Castanhal is fair. All pollutants stay as today. Pollution peaks around 11:00 PM (PM2.5: 22.4/100). 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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Castanhal's air quality reflects its position in the Pará lowland at the gateway to the northeastern Amazon region, with vehicle emissions from the BR-316 and the surrounding mixed agricultural and urban growth of this major Belém metropolitan satellite contributing local sources. Atlantic equatorial airflows generally provide background ventilation, while dry season burning from surrounding Pará Amazon deforestation generates intense PM2.5 episodes between July and November that dominate the regional air quality across the entire northeastern Pará corridor during the burning season.

Today - 16 July | Pollution peaks at 03:00

AQI:

Fair

26.1/100

PM2.5 (fine particles):

Fair

22.6/100

PM10 (coarse particles):

Good

9.7/100

NO2 (nitrogen dioxide):

Good

0.2/100

O3 (ozone):

Fair

26.1/100

SO2 (sulfur dioxide):

Good

2.3/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

0.6/100

PM1 (ultrafine particles):

Good

8.6/100

Levels show the poorest local air quality during the day

Tomorrow - 17 July | Pollution peaks at 23:00

AQI:

Fair

22.4/100

PM2.5 (fine particles):

Fair

22.4/100

PM10 (coarse particles):

Good

9.2/100

NO2 (nitrogen dioxide):

Good

0.2/100

O3 (ozone):

Fair

20.1/100

SO2 (sulfur dioxide):

Good

2.5/100

CO (carbon monoxide):

Good

0.0/100

HCHO (formaldehyde):

Good

0.7/100

PM1 (ultrafine particles):

Good

12.6/100

Frequently Asked Questions

Is air quality bad in Castanhal right now?

On 16 July 2026, overall air quality in Castanhal is fair. AQI is the main air quality indicator at 26.1/100. Pollution peaks around 3:00 AM (O3: 26.1/100).

Will air quality be worse tomorrow in Castanhal?

On 17 July 2026, air quality conditions in Castanhal will be similar to today, with AQI forecast at fair at 22.4/100. Pollution peaks around 11:00 PM (PM2.5: 22.4/100).

When is air pollution at its worst in Castanhal?

People in Castanhal tend to notice reduced air quality when native Amazon forest remnants and introduced urban trees pollen peaks, or because of vehicle emissions from the BR-316 and the surrounding mixed agricultural and urban growth of this major; a shift to wetter or windier weather typically brings noticeable relief.

Are air quality levels in Castanhal 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.

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Data provided by Airmine — Last update: 16 July 2026 at 10:33 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.

For long term forecasts and maps, see the Airmine app