SmogRank / United States / California

Air quality in La Crescenta-Montrose

California, United States. PM2.5 from 3 low-cost sensors, updated hourly.

6.7µg/m³
Good

Mean for 30 Sept, the most recent day with readings, 0.4× the WHO 24-hour guideline. No hourly readings have reached us since; some networks publish days late.

Rank, worst first

24 hours–not enough data
7 days#1,400of 2,315, at 6.3 µg/m³
30 days#852of 2,323, at 7.0 µg/m³
This year–not enough data

The last 12 months, day by day

1102031Oct 2025NovDecJan 2026FebMarAprMayJunJulAugSep2025-10-01: 8.6 µg/m³2025-10-02: 5.5 µg/m³2025-10-03: 6.1 µg/m³2025-10-04: 5.1 µg/m³2025-10-05: 5.8 µg/m³2025-10-06: 6.5 µg/m³2025-10-07: 9.0 µg/m³2025-10-08: 9.0 µg/m³2025-10-09: 7.4 µg/m³2025-10-10: 5.7 µg/m³2025-10-11: no data2025-10-12: 5.3 µg/m³2025-10-13: 6.5 µg/m³2025-10-14: 3.7 µg/m³2025-10-15: 2.9 µg/m³2025-10-16: 3.6 µg/m³2025-10-17: 4.1 µg/m³2025-10-18: 5.1 µg/m³2025-10-19: 6.0 µg/m³2025-10-20: no data2025-10-21: 8.2 µg/m³2025-10-22: 7.3 µg/m³2025-10-23: 6.4 µg/m³2025-10-24: no data2025-10-25: no data2025-10-26: 16.0 µg/m³2025-10-27: no data2025-10-28: 4.0 µg/m³2025-10-29: 3.5 µg/m³2025-10-30: no data2025-10-31: 8.9 µg/m³2025-11-01: 7.8 µg/m³2025-11-02: no data2025-11-03: 13.2 µg/m³2025-11-04: 12.5 µg/m³2025-11-05: 14.7 µg/m³2025-11-06: 8.0 µg/m³2025-11-07: 5.3 µg/m³2025-11-08: 7.0 µg/m³2025-11-09: 3.6 µg/m³2025-11-10: 4.2 µg/m³2025-11-11: 5.6 µg/m³2025-11-12: 10.7 µg/m³2025-11-13: no data2025-11-14: no data2025-11-15: 2.3 µg/m³2025-11-16: 2.5 µg/m³2025-11-17: 2.4 µg/m³2025-11-18: 3.2 µg/m³2025-11-19: 4.7 µg/m³2025-11-20: 4.0 µg/m³2025-11-21: 2.4 µg/m³2025-11-22: no data2025-11-23: no data2025-11-24: 5.8 µg/m³2025-11-25: 3.8 µg/m³2025-11-26: 3.8 µg/m³2025-11-27: 3.9 µg/m³2025-11-28: 7.9 µg/m³2025-11-29: 7.0 µg/m³2025-11-30: 14.5 µg/m³2025-12-01: 6.8 µg/m³2025-12-02: 6.6 µg/m³2025-12-03: 7.1 µg/m³2025-12-04: 4.1 µg/m³2025-12-05: 4.2 µg/m³2025-12-06: 8.5 µg/m³2025-12-07: 4.8 µg/m³2025-12-08: 4.0 µg/m³2025-12-09: 3.8 µg/m³2025-12-10: 3.6 µg/m³2025-12-11: 3.9 µg/m³2025-12-12: 4.4 µg/m³2025-12-13: 7.5 µg/m³2025-12-14: 6.4 µg/m³2025-12-15: no data2025-12-16: 6.5 µg/m³2025-12-17: 7.0 µg/m³2025-12-18: 3.8 µg/m³2025-12-19: 7.6 µg/m³2025-12-20: 13.4 µg/m³2025-12-21: 7.1 µg/m³2025-12-22: 5.2 µg/m³2025-12-23: no data2025-12-24: 3.2 µg/m³2025-12-25: 2.8 µg/m³2025-12-26: 2.8 µg/m³2025-12-27: 3.1 µg/m³2025-12-28: 3.4 µg/m³2025-12-29: no data2025-12-30: 4.0 µg/m³2025-12-31: 4.9 µg/m³2026-01-01: 3.2 µg/m³2026-01-02: 2.8 µg/m³2026-01-03: 2.4 µg/m³2026-01-04: 2.7 µg/m³2026-01-05: 4.3 µg/m³2026-01-06: 3.0 µg/m³2026-01-07: 3.1 µg/m³2026-01-08: no data2026-01-09: 4.2 µg/m³2026-01-10: 4.0 µg/m³2026-01-11: 4.0 µg/m³2026-01-12: 3.7 µg/m³2026-01-13: 3.6 µg/m³2026-01-14: 3.3 µg/m³2026-01-15: 3.6 µg/m³2026-01-16: 3.6 µg/m³2026-01-17: 4.4 µg/m³2026-01-18: 4.2 µg/m³2026-01-19: 5.0 µg/m³2026-01-20: 4.2 µg/m³2026-01-21: 8.7 µg/m³2026-01-22: 15.7 µg/m³2026-01-23: 14.3 µg/m³2026-01-24: 8.7 µg/m³2026-01-25: 4.4 µg/m³2026-01-26: 4.3 µg/m³2026-01-27: 4.2 µg/m³2026-01-28: 4.6 µg/m³2026-01-29: 3.7 µg/m³2026-01-30: 3.9 µg/m³2026-01-31: 4.3 µg/m³2026-02-01: 4.6 µg/m³2026-02-02: 6.5 µg/m³2026-02-03: 4.4 µg/m³2026-02-04: 3.5 µg/m³2026-02-05: 4.3 µg/m³2026-02-06: 8.7 µg/m³2026-02-07: 6.7 µg/m³2026-02-08: 4.9 µg/m³2026-02-09: 5.6 µg/m³2026-02-10: 7.8 µg/m³2026-02-11: 4.1 µg/m³2026-02-12: 3.9 µg/m³2026-02-13: 4.5 µg/m³2026-02-14: 8.1 µg/m³2026-02-15: 8.4 µg/m³2026-02-16: 2.9 µg/m³2026-02-17: 2.5 µg/m³2026-02-18: 3.0 µg/m³2026-02-19: 3.0 µg/m³2026-02-20: 4.1 µg/m³2026-02-21: 3.7 µg/m³2026-02-22: no data2026-02-23: 3.6 µg/m³2026-02-24: 6.0 µg/m³2026-02-25: 8.8 µg/m³2026-02-26: 4.8 µg/m³2026-02-27: 3.8 µg/m³2026-02-28: 6.4 µg/m³2026-03-01: 4.3 µg/m³2026-03-02: 4.9 µg/m³2026-03-03: 5.0 µg/m³2026-03-04: 11.8 µg/m³2026-03-05: 3.8 µg/m³2026-03-06: 3.7 µg/m³2026-03-07: 3.8 µg/m³2026-03-08: 3.4 µg/m³2026-03-09: 4.7 µg/m³2026-03-10: 8.4 µg/m³2026-03-11: 7.2 µg/m³2026-03-12: 4.4 µg/m³2026-03-13: 4.1 µg/m³2026-03-14: 6.5 µg/m³2026-03-15: no data2026-03-16: 4.7 µg/m³2026-03-17: 4.7 µg/m³2026-03-18: 5.7 µg/m³2026-03-19: 6.7 µg/m³2026-03-20: 6.4 µg/m³2026-03-21: 6.0 µg/m³2026-03-22: 11.2 µg/m³2026-03-23: 14.6 µg/m³2026-03-24: 15.1 µg/m³2026-03-25: 11.0 µg/m³2026-03-26: 9.6 µg/m³2026-03-27: 11.1 µg/m³2026-03-28: 6.4 µg/m³2026-03-29: 5.5 µg/m³2026-03-30: 8.7 µg/m³2026-03-31: 9.5 µg/m³2026-04-01: 6.2 µg/m³2026-04-02: 5.7 µg/m³2026-04-03: 4.0 µg/m³2026-04-04: 3.3 µg/m³2026-04-05: 3.7 µg/m³2026-04-06: no data2026-04-07: no data2026-04-08: no data2026-04-09: no data2026-04-10: no data2026-04-11: no data2026-04-12: no data2026-04-13: no data2026-04-14: no data2026-04-15: 4.2 µg/m³2026-04-16: no data2026-04-17: no data2026-04-18: 5.3 µg/m³2026-04-19: no data2026-04-20: no data2026-04-21: no data2026-04-22: no data2026-04-23: no data2026-04-24: no data2026-04-25: 7.2 µg/m³2026-04-26: 4.3 µg/m³2026-04-27: no data2026-04-28: no data2026-04-29: no data2026-04-30: 10.8 µg/m³2026-05-01: 11.6 µg/m³2026-05-02: no data2026-05-03: no data2026-05-04: no data2026-05-05: 3.3 µg/m³2026-05-06: no data2026-05-07: no data2026-05-08: no data2026-05-09: no data2026-05-10: 15.2 µg/m³2026-05-11: 7.0 µg/m³2026-05-12: 15.6 µg/m³2026-05-13: no data2026-05-14: no data2026-05-15: no data2026-05-16: no data2026-05-17: no data2026-05-18: no data2026-05-19: no data2026-05-20: 8.8 µg/m³2026-05-21: 8.2 µg/m³2026-05-22: 11.2 µg/m³2026-05-23: no data2026-05-24: 10.0 µg/m³2026-05-25: 7.6 µg/m³2026-05-26: no data2026-05-27: no data2026-05-28: no data2026-05-29: 4.6 µg/m³2026-05-30: no data2026-05-31: 6.5 µg/m³2026-06-01: 8.7 µg/m³2026-06-02: no data2026-06-03: no data2026-06-04: no data2026-06-05: no data2026-06-06: no data2026-06-07: no data2026-06-08: no data2026-06-09: 8.3 µg/m³2026-06-10: 7.7 µg/m³2026-06-11: no data2026-06-12: no data2026-06-13: no data2026-06-14: no data2026-06-15: no data2026-06-16: no data2026-06-17: no data2026-06-18: no data2026-06-19: no data2026-06-20: no data2026-06-21: no data2026-06-22: no data2026-06-23: 10.1 µg/m³2026-06-24: no data2026-06-25: no data2026-06-26: no data2026-06-27: 10.9 µg/m³2026-06-28: 6.2 µg/m³2026-06-29: 7.8 µg/m³2026-06-30: 8.9 µg/m³2026-07-01: 9.0 µg/m³2026-07-02: no data2026-07-03: no data2026-07-04: 6.7 µg/m³2026-07-05: no data2026-07-06: no data2026-07-07: no data2026-07-08: no data2026-07-09: no data2026-07-10: 9.5 µg/m³2026-07-11: 9.4 µg/m³2026-07-12: 6.7 µg/m³2026-07-13: 7.3 µg/m³2026-07-14: 7.4 µg/m³2026-07-15: 7.4 µg/m³2026-07-16: 7.7 µg/m³2026-07-17: no data2026-07-18: 7.1 µg/m³2026-07-19: no data2026-07-20: no data2026-07-21: no data2026-07-22: no data2026-07-23: no data2026-07-24: 5.8 µg/m³2026-07-25: no data2026-07-26: no data2026-07-27: no data2026-07-28: no data2026-07-29: no data2026-07-30: no data2026-07-31: no data2026-08-01: no data2026-08-02: no data2026-08-03: no data2026-08-04: no data2026-08-05: no data2026-08-06: no data2026-08-07: no data2026-08-08: no data2026-08-09: no data2026-08-10: no data2026-08-11: 6.9 µg/m³2026-08-12: no data2026-08-13: no data2026-08-14: 8.3 µg/m³2026-08-15: 7.4 µg/m³2026-08-16: 6.1 µg/m³2026-08-17: no data2026-08-18: no data2026-08-19: 6.2 µg/m³2026-08-20: no data2026-08-21: 6.7 µg/m³2026-08-22: no data2026-08-23: 5.2 µg/m³2026-08-24: 5.7 µg/m³2026-08-25: 6.2 µg/m³2026-08-26: 6.8 µg/m³2026-08-27: 7.0 µg/m³2026-08-28: 6.6 µg/m³2026-08-29: no data2026-08-30: 9.1 µg/m³2026-08-31: 10.9 µg/m³2026-09-01: 5.4 µg/m³2026-09-02: 6.1 µg/m³2026-09-03: 7.8 µg/m³2026-09-04: 6.4 µg/m³2026-09-05: 4.4 µg/m³2026-09-06: 4.0 µg/m³2026-09-07: 3.9 µg/m³2026-09-08: 3.4 µg/m³2026-09-09: 3.7 µg/m³2026-09-10: no data2026-09-11: no data2026-09-12: 9.4 µg/m³2026-09-13: 10.6 µg/m³2026-09-14: 10.5 µg/m³2026-09-15: 9.3 µg/m³2026-09-16: 7.5 µg/m³2026-09-17: 8.0 µg/m³2026-09-18: 8.1 µg/m³2026-09-19: 8.8 µg/m³2026-09-20: 10.9 µg/m³2026-09-21: 8.2 µg/m³2026-09-22: 9.3 µg/m³2026-09-23: 5.1 µg/m³2026-09-24: 8.5 µg/m³2026-09-25: 8.6 µg/m³2026-09-26: 4.8 µg/m³2026-09-27: 6.0 µg/m³2026-09-28: 5.1 µg/m³2026-09-29: 4.7 µg/m³2026-09-30: 6.7 µg/m³
5 of 248 measured days were over the WHO 24-hour guideline (15 µg/m³). One row per month, one square per local day.
Good0–9.0
Moderate9.1–35.4
Sensitive groups35.5–55.4
Unhealthy55.5–125.4
Very unhealthy125.5–225.4
Hazardous225.5+

Hour by hour

No hourly readings in the last few days. The chart returns when the monitors' data arrives.

Its world rank, day by day

#1#2309OctNovDecJanFebMarAprMayJunJulAugSep
Rank on each day's board (1 = most polluted city that day).

2026 against 2025, month by month

15Jan 2025: 12.8 µg/m³Jan 2026: 4.9 µg/m³JanFeb 2025: 6.0 µg/m³Feb 2026: 5.1 µg/m³FebMar 2025: 6.0 µg/m³Mar 2026: 7.1 µg/m³MarApr 2025: 7.8 µg/m³Apr 2026: 5.5 µg/m³AprMay 2025: 8.7 µg/m³May 2026: 9.1 µg/m³MayJun 2025: 11.0 µg/m³JunJul 2025: 8.8 µg/m³Jul 2026: 7.6 µg/m³JulAug 2025: 11.0 µg/m³Aug 2026: 7.1 µg/m³AugSep 2025: 7.3 µg/m³Sep 2026: 7.0 µg/m³SepOct 2025: 6.4 µg/m³OctNov 2025: 6.4 µg/m³NovDec 2025: 5.4 µg/m³Dec
Faded bars: 2025. A month shows once it has 10 measured days.

This week against past years

This weekThis week: 6.3 µg/m³6.320252025: 8.0 µg/m³8.020242024: 12.4 µg/m³12.420232023: 13.1 µg/m³13.1
Mean PM2.5 for 24 Sept to 30 Sept in each year. Dashed line: WHO 24-hour guideline.

Monitors

StationOperatorType
Mountain View ES (5404)CC0 1.0ClarityLow-cost
Clear Creek Ed Ctr (1481)CC0 1.0ClarityLow-cost
Verdugo Hills HS (8914)CC0 1.0ClarityLow-cost

No reference monitor here, so the value is the median of low-cost sensors (at least two reporting each hour). Low-cost sensors can read high in humid air. Data via OpenAQ; licences as listed. How we rank. Embed this on your site.

Other cities in United States

30-day averages, µg/m³. All of United States.

Updated 2026-10-01 21:07 UTC. Values are PM2.5 in µg/m³ (fine particles), the median of each city's monitors.