Worst air pollution Vieille Ville Sion - Sion, today and tomorrow
Today (16 July): Air quality in Vieille Ville Sion is fair. AQI and O3 are fair; PM2.5, PM10, NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 12:00 PM (O3: 37.9/100).
Tomorrow (17 July 2026): Air quality in Vieille Ville Sion is fair. All pollutants stay as today. Pollution peaks around 3:00 PM (O3: 34.8/100). 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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Vieille Ville Sion's air quality reflects Sion's historic core beneath its twin hills, with pedestrian zones limiting traffic while the enclosed Rhône valley still traps surrounding emissions under inversions.
Today - 16 July | Pollution peaks at 12:00
AQI:
Fair
37.9/100
PM2.5 (fine particles):
Good
10.8/100
PM10 (coarse particles):
Good
4.9/100
NO2 (nitrogen dioxide):
Good
19.3/100
O3 (ozone):
Fair
37.9/100
SO2 (sulfur dioxide):
Good
0.7/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
3.5/100
PM1 (ultrafine particles):
Good
11.5/100
Levels show the poorest local air quality during the day
Tomorrow - 17 July | Pollution peaks at 15:00
AQI:
Fair
34.8/100
PM2.5 (fine particles):
Good
7.8/100
PM10 (coarse particles):
Good
7.6/100
NO2 (nitrogen dioxide):
Good
16.8/100
O3 (ozone):
Fair
34.8/100
SO2 (sulfur dioxide):
Good
0.8/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
2.2/100
PM1 (ultrafine particles):
Good
5.0/100
Other Landmarks in Sion
Frequently Asked Questions
Is air quality bad in Vieille Ville Sion right now?
On 16 July 2026, overall air quality in Vieille Ville Sion is fair. AQI is the main air quality indicator at 37.9/100. Pollution peaks around 12:00 PM (O3: 37.9/100).
Will air quality be worse tomorrow in Vieille Ville Sion?
On 17 July 2026, air quality conditions in Vieille Ville Sion will be similar to today, with AQI forecast at fair at 34.8/100. Pollution peaks around 3:00 PM (O3: 34.8/100).
When is air pollution at its worst in Vieille Ville Sion?
The worst stretch for air quality at Vieille Ville Sion tends to arrive on a calm winter day, as vehicle traffic and orchard and vineyard machinery gather along the valley floor beneath the surrounding peaks. Things generally improve from spring onward, as up-valley winds return more consistently, save for an occasional hot-weather ozone peak; autumn stays mostly calm and dry.
Are air quality levels in Vieille Ville Sion 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