United States
San Diego in September
☀️ Warm dry seasonPleasant and mostly dry.
🎒 Pack: sunglasses & hat
Why September scores 9.4What goes into the score
How it works- Weather comfort10.0
- ✓Comfortable temperatures (25°C highs / 19°C lows)
- ✓Slightly humid (dew point 13.3°C)
- ✓Mostly dry (~3 mm rain)
- Air quality8.4
- ✓Good (within WHO guideline) (PM2.5 ~15 µg/m³)
- Seasonal hazards10.0
- ·No notable seasonal hazards
- Safety baseline7.5
- ·Increased caution
| Sep | Oct | |
|---|---|---|
| Score | 9.4 Excellent | 9.5 Excellent |
| Season | ☀️ Warm dry season | ☀️ Warm dry season |
| High / low | 25° / 19° | 24° / 16° |
| Rain | 3 mm | 13 mm |
| Humidity | dew pt 13° | dew pt 10° |
| PM2.5 | 15 µg/m³ | 15 µg/m³ |
Typical-month data: NASA POWER (MERRA-2 reanalysis) 2015–2024 (modelled, not a forecast). Temperatures: San Diego Airport weather-station normals. Rainfall: San Diego International Airport weather-station normals (national met service).
Holidays & crowdsSeptember 2027
Long weekendThere's at least one long weekend. Domestic travel picks up and popular spots get busier over those days.
- Labor Day 4–6 Sep · 3 days off in a row
National holidays only; regional holidays and school breaks aren't included. Source: holidays (open-source public-holiday calendar).
Explore San DiegoEvents, sights, food & souvenirs
Check event dates locallySouthern California coastal city near the Mexican border, known for mild weather year-round, beaches, Balboa Park and its zoo.
No major events on our calendar for September.
Coming up later
Gray whale migrationDate variesUsually December to March
Gray whales pass the coast on their migration to and from Baja California lagoons.
Why go: Whale-watching boats run from the harbour.
Where: Off the coast
San Diego County FairDate variesUsually June to early July
A large county fair with rides, food and concerts.
Why go: Busy on weekends.
Where: Del Mar Fairgrounds
Comic-Con InternationalDate variesUsually July
One of the world's largest comics and pop culture conventions.
Why go: Hotels fill up and prices rise; badges sell out early.
Where: San Diego Convention Center
Balboa Park
A large park with Spanish Revival buildings, gardens and many museums.
San Diego Zoo
A large, well-known zoo inside Balboa Park.
La Jolla Cove
A small cove with sea lions on the rocks, snorkelling and tide pools.
💡 Keep a distance from the animals.
USS Midway Museum
A retired aircraft carrier on the downtown waterfront, now a museum.
Old Town San Diego
A state historic park on the site of the early Mexican-era town, with adobe buildings.
Coronado Beach
A wide sandy beach in front of the Victorian-era Hotel del Coronado.
💡 Overcast mornings are common in May and June ('May Gray' and 'June Gloom').
Fish tacos
Battered or grilled fish in tortillas with cabbage and creamy sauce, inspired by Baja California.
💡 Taco shops and beach eateries
California burrito
A San Diego burrito filled with carne asada and French fries.
💡 Taco shops
Craft beer
San Diego has a large number of breweries known especially for IPAs.
💡 Breweries in North Park and Miramar
Mexican food
Traditional Mexican dishes reflecting the border location.
💡 Old Town and Barrio Logan
Craft beer
Bottles or cans from local breweries.
💡 Brewery taprooms
Surf gear
Clothing and accessories from local surf shops.
💡 Pacific Beach and Ocean Beach
Airport transfer Kiwitaxi
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