Worst air pollution Carmarthen, today and tomorrow
Today (16 July): Air quality in Carmarthen is fair. AQI, NO2, and O3 are fair; PM2.5, PM10, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 11:00 PM (NO2: 36.8/100).
Tomorrow (17 July 2026): Air quality in Carmarthen is fair. AQI improves to medium; PM2.5 increases to fair; NO2 decreases to medium; all other pollutants stay as today. Pollution peaks around 1:00 AM (NO2: 43.3/100). 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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Being part of Carmarthenshire, Carmarthen sees an air quality profile that's largely down to traffic and general town-centre activity. Cooler northerly winds help ventilate the town centre, keeping air quality at moderate levels typical for the region. The M4 sees the heaviest traffic, and that shows up clearly in local roadside monitoring.
Today - 16 July | Pollution peaks at 23:00
AQI:
Fair
36.8/100
PM2.5 (fine particles):
Good
14.5/100
PM10 (coarse particles):
Good
5.2/100
NO2 (nitrogen dioxide):
Fair
36.8/100
O3 (ozone):
Fair
31.6/100
SO2 (sulfur dioxide):
Good
7.0/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
2.8/100
PM1 (ultrafine particles):
Good
12.7/100
Levels show the poorest local air quality during the day
Tomorrow - 17 July | Pollution peaks at 01:00
AQI:
Medium
43.3/100
PM2.5 (fine particles):
Fair
21.9/100
PM10 (coarse particles):
Good
7.7/100
NO2 (nitrogen dioxide):
Medium
43.3/100
O3 (ozone):
Fair
37.8/100
SO2 (sulfur dioxide):
Good
11.9/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
4.0/100
PM1 (ultrafine particles):
Good
19.8/100
Pollen forecast in Carmarthen
View pollen forecastFrequently Asked Questions
Is air quality bad in Carmarthen right now?
On 16 July 2026, overall air quality in Carmarthen is fair. AQI is the main air quality indicator at 36.8/100. Pollution peaks around 11:00 PM (NO2: 36.8/100).
Will air quality be worse tomorrow in Carmarthen?
On 17 July 2026, air quality conditions in Carmarthen will be similar to today, with O3 forecast at fair at 37.8/100. Pollution peaks around 1:00 AM (NO2: 43.3/100).
When is air pollution at its worst in Carmarthen?
Here's the thing about Carmarthen: air quality has a clear seasonal rhythm. Once the heating goes on and the air turns still, pollution from the M4 and nearby chimneys tends to build up rather than clear. By summer, ozone tends to rise on bright days, while better ventilation generally keeps particulate and NO₂ levels lower than winter. Spring and autumn tend to be the calmer, more moderate stretches by comparison.
Are air quality levels in Carmarthen 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