San Dimas, California Weather
Coastal fog thickens at dawn. Day 76 of spring. Read this microseason across nine climate regions →
San Dimas weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 3Overcast——84°56°—
- ThursdayJun 4Foggy——89°55°+5°
- FridayJun 5Foggy——88°57°-1°
- SaturdayJun 6Overcast——82°65°-6°
- SundayJun 7Overcast——79°62°-3°
- MondayJun 8Overcast——84°61°+5°
- TuesdayJun 9Mostly Clear——85°64°+1°
Ozone at AQI 500 — peak already passed at 1 PM under clear skies. AQI flat over the last 6 hours (within ±3 points). Levels should ease through evening.
AVOID OUTDOORS Avoid outdoor exertion. Keep windows closed; use HEPA filtration indoors if available.
What's driving it
Ozone × UV × Sky
Ozone at AQI 500 — peak already passed at 1 PM under clear skies. Levels should ease through evening.
- Present
- AQI 500
- UV peak
- 4.0 at earlier today
- Sky at peak
- clear
- Projected peak
- AQI 500
PM × Wind × Precip
PM2.5 at 23.6 µg/m³, PM10 at 32.7 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.72
- Wind
- breezy
- Recent rain
- 0h in last 6h
- Pattern
- background
Trends
Seven days of AQI and PM2.5.
Hourly air-quality data from the Copernicus Atmosphere Monitoring Service, charted across the past and next several days. Dashed lines mark the AQI breakpoints at 50 (Good → Moderate) and 100 (Moderate → Unhealthy for Sensitive Groups).
The higher the clouds, the finer the weather.
- Moonrise
- 5:26 AM
- Moonset
- 3:14 PM
- In sign
- ♑︎ Capricorn
Coastal fog thickens at dawn
San Dimas at a glance
- Today vs. normal: 3°F above the seasonal normal for this latitude
- Last frost: March 12 (climatological average for this latitude)
- Microseason: Jun 1–5
- Planting window: Harvest spring lettuce before it bolts. Sow heat-tolerant greens.
Right now in the garden
Peak growing season
As of June 3, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.