Cologne Seasonal Pollution
Cologne usually records its highest OpenAQ-derived EPA AQI in January and its cleanest month in April. The page uses OpenAQ-derived daily history for 6 mapped monitoring locations in North Rhine-Westphalia, Germany.
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Average EPA AQI
43
Rank 88 of 297 cities by average AQI
PM2.5
9.0
ug/m3 annualized city average
Seasonality
January
Cleanest: April
Health indicator
0.4
cigarette-equivalent per day
Yearly EPA AQI trend
Seasonal EPA AQI heatmap
JanFebMarAprMayJunJulAugSepOctNovDec
Cologne
53
35
48
34
49
44
37
45
41
40
46
43
What this seasonality page measures
Find each city's worst and cleanest months from daily OpenAQ-derived EPA AQI.
For Cologne, the current global analytics build covers 344 daily rows from 2024-01-01 to 2024-12-31. The calculations normalize PM2.5 and PM10 observations into US EPA AQI bands so country, city, and tool pages use one consistent method.