Lahti Seasonal Pollution
Lahti usually records its highest OpenAQ-derived EPA AQI in April and its cleanest month in December. The page uses OpenAQ-derived daily history for 3 mapped monitoring locations in Päijät-Häme, Finland.
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Average EPA AQI
24
Rank 8 of 22 cities by average AQI
PM2.5
4.5
ug/m3 annualized city average
Seasonality
April
Cleanest: December
Health indicator
0.2
cigarette-equivalent per day
Yearly EPA AQI trend
Seasonal EPA AQI heatmap
JanFebMarAprMayJunJulAugSepOctNovDec
Lahti
23
25
28
32
31
26
28
25
22
18
17
14
What this seasonality page measures
Find each city's worst and cleanest months from daily OpenAQ-derived EPA AQI.
For Lahti, the current global analytics build covers 345 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.