A prolonged heatwave is set to impact San Marino and much of the San Gabriel Valley beginning Wednesday, August 20, and lasting through Sunday, August 24, 2025. Temperatures are forecast to reach the upper 90s and in some areas climb past 100 degrees, prompting warnings from health and fire officials.
Heat Risk in San Marino
The National Weather Service has issued an Extreme Heat Warning for the San Gabriel Valley from Thursday morning through Saturday evening. While San Marino is not directly adjacent to major wildland areas, the city sits within a region prone to high heat stress, poor air quality, and potential fire-related smoke drift.
Forecasters caution that extreme heat can be especially dangerous for seniors, children, pregnant women, outdoor workers, and pets. Residents are urged to take preventive steps now to avoid heat-related illness.
Countywide Fire and Weather Concerns
While San Marino itself is not in a Red Flag zone, fire danger remains elevated across Los Angeles County, particularly in the Angeles National Forest and foothill communities. Any wildfire activity could affect air quality and regional travel. Thunderstorms expected Friday through Sunday add the risk of lightning strikes, which may ignite new fires, as well as localized flooding in burn scar areas.
The Los Angeles County Fire Department has increased staffing and pre-positioned ground and air resources throughout the county in anticipation of fire activity.
Public Safety Guidance for Residents
Officials advise San Marino residents to:
- Stay Hydrated: Drink water consistently throughout the day.
- Keep Cool: Spend time in air-conditioned environments or cooling centers.
- Limit Outdoor Activity: Avoid strenuous work or exercise between 10 a.m. and 6 p.m.
- Protect Others: Check on older neighbors, family, and those without cooling options.
- Protect Pets and Children: Never leave them in parked cars, even for a few minutes.
San Marino Resources
Cooling Options Nearby
- Crowell Public Library (1890 Huntington Drive, San Marino) – Open regular hours; may serve as a community cooling refuge.
- Pasadena Senior Center (85 E. Holly St., Pasadena) – Official cooling site.
- Alhambra Civic Center Library (101 S. First St., Alhambra) – Cooling site with extended hours.
Emergency Services
- San Marino Fire Department — 2200 Huntington Drive.
- Regional coverage also provided by L.A. County Fire Station 81 (South Pasadena).
Travel and Evacuation Corridors
- Huntington Drive, San Gabriel Boulevard, and Sierra Madre Boulevard are primary routes through and out of San Marino in the event of regional emergencies.
Stay Informed
- Sign up for emergency alerts at alert.lacounty.gov.
- For cooling center information, call 2-1-1 or visit ready.lacounty.gov/heat.
