On Saturday, October 3, every coastal city in San Diego County recorded daytime high temperatures of 100 degrees Fahrenheit or above, driven by a combination of high pressure and offshore Santa Ana winds.
Record-Breaking Temperatures Across Coastal San Diego
San Diego International Airport reached 105 degrees, breaking its previous October 3 record by one degree. Oceanside Harbor recorded 101 degrees, exceeding its former daily high by seven degrees, while Vista peaked at 108 degrees, topping its previous record by four degrees, according to data monitored by the National Weather Service.
The Bottom Line
- Severe Thermal Spike: Every coastal city in San Diego County recorded temperatures at or above 100 degrees Fahrenheit on Saturday.
- Multiple Records Broken: New record highs were established in four distinct cities, with a fifth record tied.
- Relief in Sight: Daytime highs are forecast to decline on Sunday, though temperatures will remain above seasonal averages.
Localized Temperature Readings
Saturday’s readings—largely captured west of Interstate 5 through 4 p.m.—revealed extreme localized heat variations. Balboa Park registered the highest reading in the municipal network at 108 degrees, closely followed by National City at 106 degrees and Imperial Beach at 104 degrees. Other notable readings included San Diego International at 105, La Jolla at 103, Chula Vista at 103, Encinitas at 103, Carlsbad at 102, Cardiff-by-the-Sea at 102, Oceanside Harbor at 101, Mount Soledad at 101, Fort Rosecrans at 101, Naval Air Station North Island at 101, SeaWorld San Diego at 100, Torrey Pines Reserve at 100, Del Mar at 100, and Solana Beach at 100.
| Location | Saturday High (°F) | Record Status |
|---|---|---|
| Balboa Park | 108 | Noted high reading |
| National City | 106 | Noted high reading |
| San Diego International Airport | 105 | Broke Oct. 3 record by 1° |
| Imperial Beach | 104 | Noted high reading |
| Vista | 108 | Broke daily record by 4° |
Weather Conditions on Sunday
The anomalous October heat event was fueled by high atmospheric pressure working in tandem with weak-to-moderate offshore Santa Ana winds. While these winds typically bring warm conditions to Southern California, reaching triple digits across every coastal city simultaneously is an unusual occurrence for the region. Sunday’s forecast indicates a significant cooling trend, though conditions will persist above normal. El Cajon is projected to reach 103 degrees, Vista and Escondido are expected to hit 101 degrees, Encinitas will moderate to 89 degrees, and San Diego is forecasted to reach 94 degrees, roughly 20 degrees above the seasonal average.
