Czechia · The summary is refreshed every 15 minutes.
October 22
The air is unhealthy now
Olomouc
10°C
Partly cloudy
193AQI
1020hPa
Atmospheric
pressure
65%
Humidity
Olomouc now (20:00 local time): PM2.5 115.1 µg/m³. Open methodology and data in JSON: Methodology and data sources · JSON
Right now in Olomouc, PM2.5 averages 115.1 µg/m³ — “unhealthy” on the US EPA scale (approximate, from hourly readings). Mean of 4 sensors on the Atmy network, readings from 19:55–19:56 local time (17:55–17:56 UTC), summary prepared at 20:00 local time. Median: 10.3 µg/m³; range across sensors: 4.3–435.7 µg/m³.
In Olomouc the air is unhealthy right now (approximate, US EPA scale). From 07:00 to 20:00 local time the city mean PM2.5 fell from 156.3 to 115.1 µg/m³.
Light wind (2 m/s) in the evening or at night, as the air cools, possibly traps particles near the ground (a temperature inversion).
Weather now: partly cloudy, 10°C, wind 2 m/s, humidity 65%. No major change in the wind is expected in the coming hours. By 07:00 the temperature will be about 1°C.
Written automatically at 20:00 local time (18:00 UTC) from sensor measurements and the weather forecast. Values are approximate; hypotheses are marked.
7 km/h
Wind, NW
7.3 mm
Precipitation today
Monthly means of quality-checked sensors, as in the Data Hub trend; the current month is still incomplete, “-” means no data.
26%An estimate of weather conditions · not a PM2.5 forecast
14°/5°
Index by time of day
34/100Low
Night
Morning
Day
Evening14°/1°
Index by time of day
60/100Moderate
NightMorningDayEvening13°/6°
Index by time of day
55/100Moderate
NightMorningDayEvening10°/3°
Index by time of day
58/100Moderate
NightMorningDayEvening13°/4°
Index by time of day
57/100Moderate
NightMorningDayEvening12°/4°
Index by time of day
57/100Moderate
NightMorningDayEveningForecast of conditions that trap pollution near the surface
10°
Partly cloudy. Feels like 8°C
10°C83%
11°C68%6°C89%7km/hWind from the NW
22km/hWind gusts
Wind force: 2
Gusts up to 22 km/h are expected.
Czechia
14°C5°C
14°C1°C13°C6°C10°C3°C
13°C4°C12°C4°C12°C4°C13°C7°C12°C7°C11°C7°C
Highest current reading: 435.7 µg/m³ (SC #77586). Lowest: 4.3 µg/m³ (SC #93559). The list shows every sensor, highest first.
Source: atmy.ai monitoring network
Sensors in the summary by network: Sensor.Community — 4 sensors.
Atmy shows the networks’ readings after the Data Hub’s quality check: test devices and sensors that fail it are left out.
110
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10Cities with the most sensors
All sensors on the map, by city as the map assigns them; the city’s values count only the sensors that pass the Data Hub’s quality check.
Daily mean PM2.5 of the city sensors, µg/m³
Click a day to see its date and value.
A card with the current PM2.5 in Olomouc: it is refreshed every 15 minutes and links to this page. Paste the code into your site.
Czechia · City ranking · All pilot cities
Right now in Olomouc, PM2.5 averages 115.1 µg/m³ — “unhealthy” on the US EPA scale (approximate, from hourly readings). Mean of 4 sensors on the Atmy network, readings from 19:55–19:56 local time (17:55–17:56 UTC), summary prepared at 20:00 local time. Median: 10.3 µg/m³; range across sensors: 4.3–435.7 µg/m³.
The current level is “unhealthy” (US EPA scale, approximate). Everyone should reduce prolonged or heavy exertion outdoors; sensitive groups should avoid it. This is the standard guidance of the scale, not medical advice.
Highest current reading: 435.7 µg/m³ (SC #77586). Lowest: 4.3 µg/m³ (SC #93559). The list shows every sensor, highest first.
From Atmy sensors and connected public networks (citizen, experimental and government monitors), aggregated by Atmy. Values are approximate; see the methodology.
The summary is rebuilt every 15 minutes from the latest reading of each sensor, each no older than one hour.
Over the last 359 days with data, the mean daily PM2.5 in Olomouc was 28.2 µg/m³ — 5.6 times the WHO annual guideline (5 µg/m³). Over the last 30 days: 84.2 µg/m³. From Atmy's archive of daily city means.
In Atmy's daily archive, the cleanest month of the last year was May 2026: 3.5 µg/m³ on average.
The most polluted month of the last year was August 2026: 76.2 µg/m³ on average.
From November to March the mean daily PM2.5 was 17.1 µg/m³, from June to August 37.4 µg/m³ (last 365 days).
The daily value is the Data Hub’s: the mean of the city’s sensors that passed the nightly quality check, each with at least 12 valid hours, and only with sensors at four places 500 m apart; days are UTC.
“Now” uses the same sensors and rule: the mean of their latest readings, each at most 60 minutes old, shown only with sensors at four places 500 m apart reporting.
Source: public Atmy monitoring data. Methodology and data sources · Data terms
