Worst air pollution Kosai, today and tomorrow
Today (10 August): Air quality in Kosai is medium. AQI and O3 are medium; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 4:00 PM (O3: 55.5/100).
Tomorrow (11 August 2026): Air quality in Kosai is poor. AQI worsens to poor; O3 increases to poor; all other pollutants stay as today. Pollution peaks around 2:00 PM (O3: 61.4/100). 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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Kosai's air quality reflects the Shizuoka Prefecture Hamana Lake coastal position, with vehicle traffic on surrounding roads and the manufacturing, automotive parts, and services corridor contributing local sources. Consistent Pacific and Enshunada Bay maritime breezes provide coastal ventilation, while summer photochemical ozone from the broader Shizuoka corridor is the primary warm-season concern and Kosai generally maintains moderate to good conditions for a Shizuoka coastal city throughout most of the year.
Today - 10 August | Pollution peaks at 16:00
AQI:
Medium
55.5/100
PM2.5 (fine particles):
Good
14.2/100
PM10 (coarse particles):
Good
4.3/100
NO2 (nitrogen dioxide):
Good
6.9/100
O3 (ozone):
Medium
55.5/100
SO2 (sulfur dioxide):
Good
3.5/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
15.5/100
PM1 (ultrafine particles):
Good
16.7/100
Levels show the poorest local air quality during the day
Tomorrow - 11 August | Pollution peaks at 14:00
AQI:
Poor
61.4/100
PM2.5 (fine particles):
Good
10.9/100
PM10 (coarse particles):
Good
3.2/100
NO2 (nitrogen dioxide):
Good
9.6/100
O3 (ozone):
Poor
61.4/100
SO2 (sulfur dioxide):
Good
3.5/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
7.4/100
PM1 (ultrafine particles):
Good
13.1/100
Frequently Asked Questions
Is air quality bad in Kosai right now?
On 10 August 2026, overall air quality in Kosai is medium. AQI is the main air quality indicator at 55.5/100. Pollution peaks around 4:00 PM (O3: 55.5/100).
Will air quality be worse tomorrow in Kosai?
On 11 August 2026, air quality conditions in Kosai will be worse than today, with AQI forecast at poor at 61.4/100. Pollution peaks around 2:00 PM (O3: 61.4/100).
When is air pollution at its worst in Kosai?
Pollution in Kosai typically rises when traffic on the surrounding roads, steel, cement, and chemical production, together with manufacturing and food processing combine, especially once warm, sunny weather takes hold. Strong sunlight reacting with local emissions drives up ground-level ozone. Maritime airflow normally ventilates the area well, though calmer spells let levels rise.
Are air quality levels in Kosai 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: 9 August 2026 at 20:27 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.
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