Worst air pollution Cilfynydd, today and tomorrow
Today (20 September): Air quality in Cilfynydd is moderate. AQI and NO2 are moderate; PM2.5, PM10, O3, and PM1 are fair; SO2, CO, and HCHO are good. Pollution peaks around 9:00 PM (NO2: 40.9/100).
Tomorrow (21 September 2026): Air quality in Cilfynydd is poor. AQI worsens to poor; PM2.5 increases to moderate; NO2 increases to poor; PM1 increases to moderate; all other pollutants stay as today. Pollution peaks around 8:00 PM (NO2: 62.0/100). Airmine updates local air quality forecasts four times daily.
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Rush-hour queues near the A55 are usually when readings climb the most. Cilfynydd's air quality reflects its position within Rhondda Cynon Taf, with local traffic and the town's built-up core as the main contributors. Northwesterly winds off the coast usually ensure decent dispersal, so levels generally stay within the moderate range typical of UK towns.
Today - 20 September | Pollution peaks at 21:00
AQI:
Moderate
40.9/100
PM2.5 (fine particles):
Fair
38.4/100
PM10 (coarse particles):
Fair
23.8/100
NO2 (nitrogen dioxide):
Moderate
40.9/100
O3 (ozone):
Fair
26.3/100
SO2 (sulfur dioxide):
Good
5.6/100
CO (carbon monoxide):
Good
0.9/100
HCHO (formaldehyde):
Good
8.3/100
PM1 (ultrafine particles):
Fair
26.5/100
Levels show the poorest local air quality during the day
Tomorrow - 21 September | Pollution peaks at 20:00
AQI:
Poor
62.0/100
PM2.5 (fine particles):
Moderate
46.8/100
PM10 (coarse particles):
Fair
38.7/100
NO2 (nitrogen dioxide):
Poor
62.0/100
O3 (ozone):
Fair
27.6/100
SO2 (sulfur dioxide):
Good
10.9/100
CO (carbon monoxide):
Good
1.3/100
HCHO (formaldehyde):
Good
15.7/100
PM1 (ultrafine particles):
Moderate
42.6/100
Pollen forecast in Cilfynydd
View pollen forecastFrequently Asked Questions
Is air quality bad in Cilfynydd right now?
On 20 September 2026, overall air quality in Cilfynydd is moderate. AQI is the main air quality indicator at 40.9/100. Pollution peaks around 9:00 PM (NO2: 40.9/100).
Will air quality be worse tomorrow in Cilfynydd?
On 21 September 2026, air quality conditions in Cilfynydd will be worse than today, with AQI forecast at poor at 62.0/100. Pollution peaks around 8:00 PM (NO2: 62.0/100).
When is air pollution at its worst in Cilfynydd?
Seasons make a real difference to air quality in Cilfynydd, more than most people realise. Summer sunshine can drive up ozone locally, though overall air generally moves and clears more freely than in winter. Winter tends to be worst, with wood burning, home heating, and still, cold air trapping traffic fumes from the A55 closer to ground level. Spring and autumn don't usually cause much concern, sitting comfortably between winter's peak and summer's ozone spikes.
Are air quality levels in Cilfynydd 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 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.
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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