Arnold, California Weather
Coastal fog thickens at dawn. Day 76 of spring. Read this microseason across nine climate regions →
Arnold weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 3Overcast——78°57°—
- ThursdayJun 4Clear——79°59°+1°
- FridayJun 5Partly Cloudy——85°60°+6°
- SaturdayJun 6Overcast——76°55°-9°
- SundayJun 7Mostly Clear——73°50°-3°
- MondayJun 8Overcast12%—75°52°+2°
- TuesdayJun 9Overcast12%—72°52°-3°
Ozone at AQI 85 now. AQI flat over the last 6 hours (within ±4 points). With UV 9.7 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 110 by mid-afternoon.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
Ozone × UV × Sky
Ozone at AQI 85 now. With UV 9.7 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 110 by mid-afternoon.
- Present
- AQI 85
- UV peak
- 9.7 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 110
PM × Wind × Precip
PM2.5/PM10 ratio 0.61 with 8 mph wind — characteristic of long-range haze transport rather than a local source.
- PM2.5/PM10
- 0.61
- Wind
- light
- Recent rain
- 0h in last 6h
- Pattern
- transport
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
- 5:50 AM
- Moonset
- 3:11 PM
- In sign
- ♑︎ Capricorn
Coastal fog thickens at dawn
Arnold at a glance
- Today vs. normal: 77°F — typical for the season
- Last frost: April 5 (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.