Worst air pollution Julian, today and tomorrow
Today (15 July): Air quality in Julian is fair. PM2.5 and O3 are fair; AQI and PM10 are medium; NO2, SO2, CO, HCHO, and PM1 are good. Pollution peaks around 9:00 AM (PM10: 44.2/100).
Tomorrow (16 July 2026): Air quality in Julian is fair. AQI worsens to fair; PM10 increases to fair; all other pollutants stay as today. Pollution peaks around 5:00 AM (PM10: 40.0/100). 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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Air quality in Julian is driven mostly by mountain air above the coastal haze layer — elevation keeps it above much of the coastal smog layer. Most days bring generally favorable conditions here, with occasional exceptions tied to shifting weather patterns. Visitors and residents alike tend to notice the clearest air outside the warmest summer weeks.
Today - 15 July | Pollution peaks at 09:00
AQI:
Medium
44.2/100
PM2.5 (fine particles):
Fair
33.5/100
PM10 (coarse particles):
Medium
44.2/100
NO2 (nitrogen dioxide):
Good
4.7/100
O3 (ozone):
Fair
28.3/100
SO2 (sulfur dioxide):
Good
10.9/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
0.9/100
PM1 (ultrafine particles):
Good
6.2/100
Levels show the poorest local air quality during the day
Tomorrow - 16 July | Pollution peaks at 05:00
AQI:
Fair
40.0/100
PM2.5 (fine particles):
Fair
25.2/100
PM10 (coarse particles):
Fair
40.0/100
NO2 (nitrogen dioxide):
Good
6.3/100
O3 (ozone):
Fair
28.9/100
SO2 (sulfur dioxide):
Good
11.8/100
CO (carbon monoxide):
Good
0.0/100
HCHO (formaldehyde):
Good
0.9/100
PM1 (ultrafine particles):
Good
5.7/100
Pollen forecast in Julian
View pollen forecastFrequently Asked Questions
Is air quality bad in Julian right now?
On 15 July 2026, overall air quality in Julian is fair. PM2.5 is the main pollutant at 33.5/100. Pollution peaks around 9:00 AM (PM10: 44.2/100).
Will air quality be worse tomorrow in Julian?
On 16 July 2026, air quality conditions in Julian will be similar to today, with AQI forecast at fair at 40.0/100. Pollution peaks around 5:00 AM (PM10: 40.0/100).
When is air pollution at its worst in Julian?
Conditions in Julian vary noticeably across the seasons — the shortest stretch of clean air usually falls in the wetter winter months, whereas from August into October, wildfire smoke can add sharp particulate spikes on top of the usual summer ozone. Coastal breezes offer some relief compared to inland valley locations that see heavier smog buildup.
Are air quality levels in Julian 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