Half Moon Bay, California Weather
Summer heat deepens across the valleys. Day 15 of summer. Read this microseason across nine climate regions →
Half Moon Bay weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 5Foggy——59°54°—
- MondayJul 6Foggy——59°54°0°
- TuesdayJul 7Foggy——65°54°+6°
- WednesdayJul 8Overcast——70°56°+5°
- ThursdayJul 9Overcast——66°56°-4°
- FridayJul 10Overcast——72°53°+6°
- SaturdayJul 11Overcast——73°55°+1°
AQI 26 (Good), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 4.5 µg/m³ (AQI 25) with a 0.66 fine-to-coarse ratio and 6 mph wind — combustion smoke trapped in calm air, not road dust.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
PM × Wind × Precip
PM2.5 at 4.5 µg/m³ (AQI 25) with a 0.66 fine-to-coarse ratio and 6 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.66
- Wind
- light
- Recent rain
- 0h in last 6h
- Pattern
- stagnant smoke
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).
If the first of July be rainy weather, 'twill rain more or less for four weeks together.
- Moonrise
- 11:28 PM
- Moonset
- 11:28 AM
- In sign
- ♓︎ Pisces
Summer heat deepens across the valleys
Half Moon Bay at a glance
- Today vs. normal: 18°F below the seasonal normal for this latitude
- Last frost: April 1 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
ZIP code: 94019
16-Day Forecast — Half Moon Bay
- Sun59°54°9%
- Mon59°54°4%
- Tue65°54°2%
- Wed70°56°0%
- Thu66°56°0%
- Fri72°53°0%
- Sat73°55°1%
- Sun75°53°1%
- Mon84°56°2%
- Tue78°57°5%
- Wed63°57°0%
- Thu95°62°1%
- Fri96°62°0%
- Sat89°60°0%
- Sun73°57°3%
- Mon69°55°6%
Forecast data from Open-Meteo (CC BY 4.0).
Right now in the garden
Peak growing season
As of July 5, 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.
ZIP codes in Half Moon Bay
- 94019