San Diego County, December 17, 2025
A dense fog advisory has been issued for the coastal areas of San Diego County, resulting in visibility dropping to one-quarter mile or less. This advisory lasts until 9:00 AM PST and poses hazardous driving conditions on local highways. Motorists are urged to exercise caution, slow down, use headlights, and maintain safe following distances. The fog is expected to cause delays, and it’s essential for drivers to stay informed through the National Weather Service for updates.
Dense Fog Advisory Issued for San Diego County Coastal Areas
San Diego, CA – A dense fog advisory is currently in effect for San Diego County’s coastal areas, with visibility expected to drop to one-quarter mile or less. This advisory is set to remain in effect until 9:00 AM PST this morning. Drivers are strongly advised to exercise caution due to hazardous driving conditions.
Details of the Advisory
- What: Visibility one-quarter mile or less in dense fog.
- Where: San Diego County Coastal Areas.
- When: Until 9:00 AM PST this morning.
- Impacts: Low visibility could make driving conditions hazardous, especially along I-5, portions of I-8, I-805, and Highway 163.
Safety Recommendations
If you are driving in the affected areas, please follow these safety guidelines:
- Slow down: Reduce your speed to accommodate limited visibility.
- Use headlights: Turn on your low beam headlights to increase your visibility to other drivers.
- Increase following distance: Leave plenty of space between your vehicle and the one ahead to allow for sudden stops.
Understanding Dense Fog
Dense fog is a weather phenomenon characterized by a thick layer of fog that significantly reduces visibility. It typically forms when there is high relative humidity, calm winds, and rapid cooling during the night. In California, dense fog can occur in various regions, including coastal areas like San Diego County. Such conditions can lead to hazardous driving situations, making it essential for motorists to exercise increased caution during these periods.
Additional Information
For the most current weather updates and any further advisories, please refer to the National Weather Service’s San Diego office. Staying informed will help ensure your safety during adverse weather conditions.
Frequently Asked Questions
- What is a dense fog advisory?
- A dense fog advisory is issued when visibility is expected to be reduced to one-quarter mile or less due to dense fog, making driving conditions hazardous.
- How long is the dense fog advisory in effect?
- The advisory is in effect until 9:00 AM PST this morning.
- Which areas are affected by the advisory?
- The advisory affects San Diego County’s coastal areas.
- What should drivers do during a dense fog advisory?
- Drivers should slow down, use their low beam headlights, and leave plenty of distance between vehicles to ensure safety.
- Where can I find more information about the advisory?
- For the most current weather updates and any further advisories, please refer to the National Weather Service’s San Diego office.
| Feature | Details |
|---|---|
| Advisory Type | Dense Fog Advisory |
| Effective Area | San Diego County Coastal Areas |
| Visibility | One-quarter mile or less |
| Advisory Duration | Until 9:00 AM PST this morning |
| Impacted Routes | I-5, I-8, I-805, Highway 163 |
| Safety Recommendations | Slow down, use low beam headlights, increase following distance |
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Author: STAFF HERE SAN DIEGO WRITER
The SAN DIEGO STAFF WRITER represents the experienced team at HERESanDiego.com, your go-to source for actionable local news and information in San Diego, San Diego County, and beyond. Specializing in "news you can use," we cover essential topics like product reviews for personal and business needs, local business directories, politics, real estate trends, neighborhood insights, and state news affecting the area—with deep expertise drawn from years of dedicated reporting and strong community input, including local press releases and business updates. We deliver top reporting on high-value events such as Comic-Con International, San Diego County Fair, and San Diego Pride Festival. Our coverage extends to key organizations like the San Diego Regional Chamber of Commerce and United Way of San Diego County, plus leading businesses in biotechnology, healthcare, and technology that power the local economy such as Qualcomm, Illumina, and Scripps Health. As part of the broader HERE network, including HEREAnaheim.com, HEREBeverlyHills.com, HERECostaMesa.com, HERECoronado.com, HEREHollywood.com, HEREHuntingtonBeach.com, HERELongBeach.com, HERELosAngeles.com, HEREMissionViejo.com, and HERESantaAna.com, we provide comprehensive, credible insights into California's dynamic landscape.
