Diamond Bar, California Weather
Summer heat deepens across the valleys. Day 15 of summer. Read this microseason across nine climate regions →
Diamond Bar weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJul 5Overcast——87°63°—
- MondayJul 6Clear——88°58°+1°
- TuesdayJul 7Clear——91°60°+3°
- WednesdayJul 8Clear——95°72°+4°
- ThursdayJul 9Clear——95°75°0°
- FridayJul 10Overcast——93°74°-2°
- SaturdayJul 11Overcast——88°72°-5°
AQI 61 (Moderate), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 18.9 µg/m³ (AQI 69) with a 0.82 fine-to-coarse ratio and 4 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 18.9 µg/m³ (AQI 69) with a 0.82 fine-to-coarse ratio and 4 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.82
- Wind
- calm
- 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
- 11:07 PM
- Moonset
- 11:10 AM
- In sign
- ♓︎ Pisces
Summer heat deepens across the valleys
Diamond Bar at a glance
- Today vs. normal: 80°F — typical for the season
- Last frost: March 11 (climatological average for this latitude)
- Microseason: Jul 1–5
- Planting window: Harvest early potatoes. Begin drying onions on the surface.
ZIP code: 91765
16-Day Forecast — Diamond Bar
- Sun87°63°1%
- Mon88°58°1%
- Tue91°60°0%
- Wed95°72°0%
- Thu95°75°0%
- Fri93°74°0%
- Sat88°72°0%
- Sun86°71°1%
- Mon97°74°5%
- Tue101°79°10%
- Wed99°80°4%
- Thu102°82°10%
- Fri101°83°10%
- Sat97°81°10%
- Sun100°80°19%
- Mon101°79°19%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near Diamond Bar
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 Diamond Bar
- 91789
- 91765