Alta, California Weather
Coastal fog thickens at dawn. Day 77 of spring. Read this microseason across nine climate regions →
Alta weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 3Overcast——80°60°—
- ThursdayJun 4Clear——78°61°-2°
- FridayJun 5Overcast——84°60°+6°
- SaturdayJun 6Overcast——73°50°-11°
- SundayJun 7Overcast——71°47°-2°
- MondayJun 8Drizzle17%0.14″67°49°-4°
- TuesdayJun 9Light Drizzle18%—63°45°-4°
Ozone at AQI 73 — peak already passed at 1 PM under clear skies. AQI up 44 in the last 6 hours — air quality is degrading. Levels should ease through evening.
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 73 — peak already passed at 1 PM under clear skies. Levels should ease through evening.
- Present
- AQI 73
- UV peak
- 1.0 at earlier today
- Sky at peak
- clear
- Projected peak
- AQI 73
PM × Wind × Precip
PM2.5/PM10 ratio 0.66 with 7 mph wind — characteristic of long-range haze transport rather than a local source.
- PM2.5/PM10
- 0.66
- 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).
A summer fog for fair, a winter fog for rain.
- Moonrise
- 6:33 AM
- Moonset
- 4:13 PM
- In sign
- ♑︎ Capricorn
Coastal fog thickens at dawn
Alta at a glance
- Today vs. normal: 75°F — typical for the season
- Last frost: April 11 (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 4, 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.