SmogRank / Episodes / United States
California, United States, November 2025
For 3 days, from 1 to 3 November 2025, 14 cities in the United States had PM2.5 at least twice their usual for the time of year. The worst reading was Pasadena, California, United States: 39.0 µg/m³ on 3 November, about 7.8× its usual 4.3.
No cause named We have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached 14 in 1 country
Days 3 1 to 3 November 2025
Worst day 2 November 8 cities counted
Furthest above usual 7.8× Pasadena
Day by day
Play 2 November 8 cities at twice their usual or more
Lancaster Bakersfield Santa Clarita Fillmore Simi Valley La Crescenta-Montrose Burbank Agoura Thousand Oaks Delano Ridgecrest Oxnard Inglewood Porterville Glendora Torrance Long Beach Victorville Santa Barbara Tulare Goleta Mission Viejo Lake Elsinore Orcutt Nipomo Lompoc Banning Arroyo Grande Temecula Fresno Clovis San Luis Obispo Oceanside Atascadero Madera Poway Indio San Diego El Cajon Chula Vista Merced Summerlin South Turlock Hollister Enterprise Spring Valley Salinas Las Vegas Prunedale Gilroy Brawley Henderson Seaside Watsonville El Centro Boulder City Calexico Mexicali Live Oak Santa Cruz San Jose Sunnyvale Mountain View Palo Alto Redwood City Yuma Mesquite Visalia Compton Hanford Corcoran Anaheim Los Angeles Hawthorne Jurupa Valley Carson Fontana Riverside Lomita Santa Monica Pasadena 29 Oct 30 31 1 Nov 2 3 4 5 6 Every measured city in the area, coloured by its PM2.5 that day; a dark ring marks a city at twice its usual or more. Bars: cities counted each day, coloured by their median level. Choose a day or press play; without JavaScript, the days link to that day's world ranking.
How it spread
Pasadena Pasadena, 29 October: 0.4 µg/m³, 0.1× usual Pasadena, 30 October: 2.6 µg/m³, 0.5× usual Pasadena, 31 October: 18.5 µg/m³, 3.7× usual Pasadena, 1 November: 31.9 µg/m³, 6.4× usual Pasadena, 2 November: 33.1 µg/m³, 6.6× usual Pasadena, 3 November: 39.0 µg/m³, 7.8× usual Pasadena, 4 November: 40.3 µg/m³, 8.1× usual Pasadena, 5 November: 22.0 µg/m³, 4.4× usual Pasadena, 6 November: 13.9 µg/m³, 2.8× usual Riverside Riverside, 29 October: 7.8 µg/m³, 0.7× usual Riverside, 30 October: 11.7 µg/m³, 1.1× usual Riverside, 31 October: 19.1 µg/m³, 1.8× usual Riverside, 1 November: 29.5 µg/m³, 2.8× usual Riverside, 2 November: 36.6 µg/m³, 3.5× usual Riverside, 3 November: 27.6 µg/m³, 2.6× usual Riverside, 4 November: 21.2 µg/m³, 2.0× usual Riverside, 5 November: 19.2 µg/m³, 1.8× usual Riverside, 6 November: 14.3 µg/m³, 1.3× usual Jurupa Valley Jurupa Valley, 29 October: 15.1 µg/m³, 1.2× usual Jurupa Valley, 30 October: 14.1 µg/m³, 1.1× usual Jurupa Valley, 31 October: 18.5 µg/m³, 1.4× usual Jurupa Valley, 1 November: 29.5 µg/m³, 2.3× usual Jurupa Valley, 2 November: 35.2 µg/m³, 2.7× usual Jurupa Valley, 3 November: 26.0 µg/m³, 2.0× usual Jurupa Valley, 4 November: 20.1 µg/m³, 1.6× usual Jurupa Valley, 5 November: 16.1 µg/m³, 1.2× usual Jurupa Valley, 6 November: 14.1 µg/m³, 1.1× usual Carson Carson, 29 October: 8.4 µg/m³, 0.9× usual Carson, 30 October: no reading Carson, 31 October: 12.4 µg/m³, 1.3× usual Carson, 1 November: 27.3 µg/m³, 2.8× usual Carson, 2 November: no reading Carson, 3 November: 21.9 µg/m³, 2.2× usual Carson, 4 November: 20.5 µg/m³, 2.1× usual Carson, 5 November: 8.4 µg/m³, 0.9× usual Carson, 6 November: 8.2 µg/m³, 0.8× usual Lomita Lomita, 29 October: 6.3 µg/m³, 0.9× usual Lomita, 30 October: no reading Lomita, 31 October: 10.9 µg/m³, 1.5× usual Lomita, 1 November: 26.2 µg/m³, 3.6× usual Lomita, 2 November: no reading Lomita, 3 November: 16.7 µg/m³, 2.3× usual Lomita, 4 November: 16.4 µg/m³, 2.2× usual Lomita, 5 November: 6.5 µg/m³, 0.9× usual Lomita, 6 November: 6.8 µg/m³, 0.9× usual Hawthorne Hawthorne, 29 October: 10.7 µg/m³, 1.0× usual Hawthorne, 30 October: no reading Hawthorne, 31 October: 15.4 µg/m³, 1.5× usual Hawthorne, 1 November: 26.0 µg/m³, 2.5× usual Hawthorne, 2 November: no reading Hawthorne, 3 November: 22.5 µg/m³, 2.1× usual Hawthorne, 4 November: 22.9 µg/m³, 2.2× usual Hawthorne, 5 November: 10.3 µg/m³, 1.0× usual Hawthorne, 6 November: 11.0 µg/m³, 1.0× usual Santa Monica Santa Monica, 29 October: 7.5 µg/m³, 1.0× usual Santa Monica, 30 October: 7.2 µg/m³, 1.0× usual Santa Monica, 31 October: 17.3 µg/m³, 2.3× usual Santa Monica, 1 November: 19.3 µg/m³, 2.6× usual Santa Monica, 2 November: 37.6 µg/m³, 5.0× usual Santa Monica, 3 November: 22.7 µg/m³, 3.0× usual Santa Monica, 4 November: 21.0 µg/m³, 2.8× usual Santa Monica, 5 November: 7.8 µg/m³, 1.0× usual Santa Monica, 6 November: 7.5 µg/m³, 1.0× usual Visalia Visalia, 29 October: 18.6 µg/m³, 1.2× usual Visalia, 30 October: 19.5 µg/m³, 1.3× usual Visalia, 31 October: 24.2 µg/m³, 1.6× usual Visalia, 1 November: 28.1 µg/m³, 1.8× usual Visalia, 2 November: 30.9 µg/m³, 2.0× usual Visalia, 3 November: 23.4 µg/m³, 1.5× usual Visalia, 4 November: 17.4 µg/m³, 1.1× usual Visalia, 5 November: 9.6 µg/m³, 0.6× usual Visalia, 6 November: 8.5 µg/m³, 0.6× usual Fontana Fontana, 29 October: 9.1 µg/m³, 0.9× usual Fontana, 30 October: 9.6 µg/m³, 1.0× usual Fontana, 31 October: 15.1 µg/m³, 1.5× usual Fontana, 1 November: 23.1 µg/m³, 2.3× usual Fontana, 2 November: 29.6 µg/m³, 3.0× usual Fontana, 3 November: 27.0 µg/m³, 2.7× usual Fontana, 4 November: 19.6 µg/m³, 2.0× usual Fontana, 5 November: 21.1 µg/m³, 2.1× usual Fontana, 6 November: 14.2 µg/m³, 1.4× usual Anaheim Anaheim, 29 October: 13.7 µg/m³, 1.2× usual Anaheim, 30 October: 11.2 µg/m³, 1.0× usual Anaheim, 31 October: 10.5 µg/m³, 0.9× usual Anaheim, 1 November: 19.0 µg/m³, 1.7× usual Anaheim, 2 November: 26.7 µg/m³, 2.4× usual Anaheim, 3 November: 16.2 µg/m³, 1.4× usual Anaheim, 4 November: 17.1 µg/m³, 1.5× usual Anaheim, 5 November: 8.0 µg/m³, 0.7× usual Anaheim, 6 November: 6.8 µg/m³, 0.6× usual Compton Compton, 29 October: 8.7 µg/m³, 0.7× usual Compton, 30 October: 13.3 µg/m³, 1.0× usual Compton, 31 October: 10.6 µg/m³, 0.8× usual Compton, 1 November: 23.4 µg/m³, 1.8× usual Compton, 2 November: 26.3 µg/m³, 2.0× usual Compton, 3 November: 24.6 µg/m³, 1.9× usual Compton, 4 November: 23.3 µg/m³, 1.8× usual Compton, 5 November: 8.0 µg/m³, 0.6× usual Compton, 6 November: 7.2 µg/m³, 0.5× usual Hanford Hanford, 29 October: 16.6 µg/m³, 1.2× usual Hanford, 30 October: 24.4 µg/m³, 1.7× usual Hanford, 31 October: 15.5 µg/m³, 1.1× usual Hanford, 1 November: 22.9 µg/m³, 1.6× usual Hanford, 2 November: 17.1 µg/m³, 1.2× usual Hanford, 3 November: 30.2 µg/m³, 2.1× usual Hanford, 4 November: 15.8 µg/m³, 1.1× usual Hanford, 5 November: 13.5 µg/m³, 0.9× usual Hanford, 6 November: 7.0 µg/m³, 0.5× usual Corcoran Corcoran, 29 October: 16.7 µg/m³, 1.4× usual Corcoran, 30 October: 23.9 µg/m³, 2.0× usual Corcoran, 31 October: 17.7 µg/m³, 1.5× usual Corcoran, 1 November: 17.8 µg/m³, 1.5× usual Corcoran, 2 November: 20.3 µg/m³, 1.7× usual Corcoran, 3 November: 27.3 µg/m³, 2.2× usual Corcoran, 4 November: 12.4 µg/m³, 1.0× usual Corcoran, 5 November: 5.2 µg/m³, 0.4× usual Corcoran, 6 November: no reading Los Angeles Los Angeles, 29 October: 7.0 µg/m³, 0.6× usual Los Angeles, 30 October: 10.7 µg/m³, 1.0× usual Los Angeles, 31 October: 15.9 µg/m³, 1.5× usual Los Angeles, 1 November: 22.1 µg/m³, 2.0× usual Los Angeles, 2 November: 24.7 µg/m³, 2.3× usual Los Angeles, 3 November: 26.5 µg/m³, 2.5× usual Los Angeles, 4 November: 22.2 µg/m³, 2.1× usual Los Angeles, 5 November: 8.6 µg/m³, 0.8× usual Los Angeles, 6 November: 9.2 µg/m³, 0.9× usual 29 Oct 30 31 1 Nov 2 3 4 5 6 Every counted city, in the order the episode reached them, 3 days before to 3 after. Each square is a day, coloured by that day's PM2.5; outlined: at twice the city's usual or more. Good 0–50
Moderate 51–100
Sensitive groups 101–150
Unhealthy 151–200
Very unhealthy 201–300
Hazardous 301+
Every city it reached
City Days Highest Usual Above usual
Pasadena California, United States 3 4 November 4.3 8.1× Santa Monica California, United States 1 2 November 7.5 5.0× Lomita California, United States 1 1 November 7.3 3.6× Riverside California, United States 3 2 November 10.6 3.5× Fontana California, United States 2 2 November 10.0 3.0× Carson California, United States 1 1 November 9.8 2.8× Jurupa Valley California, United States 3 2 November 12.9 2.7× Los Angeles California, United States 1 3 November 10.8 2.5× Hawthorne California, United States 1 1 November 10.6 2.5× Anaheim California, United States 1 2 November 11.2 2.4× Corcoran California, United States 1 3 November 12.2 2.2× Hanford California, United States 1 3 November 14.4 2.1× Visalia California, United States 1 2 November 15.3 2.0× Compton California, United States 1 2 November 13.2 2.0×
Daily means in µg/m³. Usual: the city's median for this time of year (its days within 21 days of the date, every year, leaving out the week around it). Above usual: its highest day against that.
Against other episodes in the United States
Number 54 of 98 episodes in the United States since our records began, by cities reached.
North-eastern United States and Canada, June and July 2023 279 North-eastern United States and Canada, July 2026 264 North-eastern United States and Canada, May and June 2023 260 North-eastern United States and Canada, July and August 2025 241 North-eastern United States and Canada, July 2023 241 North-eastern United States and Canada, June 2025 196 North-eastern United States and Canada, June 2023 161 North-eastern United States and Canada, July 2025 119 North-western United States and Canada, August 2023 110 North-eastern United States, June 2025 104 North-western United States and Canada, August 2026 99 North-eastern United States and Canada, February 2026 96 California, United States, November 2025 14 Bars: cities reached; colour: the level of the episode's highest daily reading. All 98 .
Use this page SmogRank, California, United States, November 2025: 14 cities with PM2.5 at twice their usual or more, 1 to 3 November 2025, smogrank.com/episodes/2025-11-california-united-states (accessed 2 October 2026).
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You're welcome to reuse a single chart, image or figure with this citation and a link. Terms .
An episode is a run of days when many cities close to each other (four or more within 350 km on a day, 8 or more in all) each had a daily PM2.5 mean of at least 25 µg/m³ and at least 2 times their usual for that time of year. Found in our own measurements, not picked by hand. How we find episodes . Values are each city's daily mean of its own monitors; causes are the usual kinds for a pattern like this, not a confirmed source.
