Current Conditions

Diamond Bar, California

80°F27°C

Clear

Wind

SW 8 mph12 km/h

Humidity

32%

Cloud Cover

As of Wednesday, September 2, 2026 at 1:55 PM PDT

Today's Outlook

Day

Mostly clear and warm, with a high of 80°F27°C and morning low of 76°F24°C. Breezy from the SW at 7 to 8 mph11 to 12 km/h. Dry air.

Night

Mostly clear, with a low around 66°F19°C. Light wind from the SW around 3 mph4 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Clear	High 80°F27°C	Low 66°F19°C	Precip 0 in0 mm—	Cloud 0%	Wind SW 5 mph8 km/h	Wednesday: Mostly clear and warm, with a high of 80°F27°C and morning low of 76°F24°C. Breezy from the SW at 7 to 8 mph11 to 12 km/h. Dry air. Wednesday Night: Mostly clear, with a low around 66°F19°C. Light wind from the SW around 3 mph4 km/h.
Clear	High 80°F27°C	Low 61°F16°C	Precip 0 in0 mm—	Cloud 3%	Wind SSW 4 mph6 km/h	Thursday: Mostly clear and warm, with a high of 80°F27°C and morning low of 66°F19°C. Breezy from the SSW at 5 to 8 mph9 to 12 km/h. Thursday Night: Mostly clear, with a low around 61°F16°C. Light wind from the SSW around 2 mph4 km/h.
Clear	High 81°F27°C	Low 62°F17°C	Precip 0 in0 mm—	Cloud 12%	Wind SSW 3 mph6 km/h	Friday: Mostly clear and warm, with a high of 81°F27°C and morning low of 65°F19°C. Breezy from the SSW at 5 to 7 mph8 to 11 km/h. Friday Night: Mostly clear, with a low around 62°F17°C. Light wind from the SSW around 2 mph3 km/h.
Clear	High 85°F29°C	Low 62°F17°C	Precip 0 in0.1 mm4%	Cloud 8%	Wind SSW 3 mph5 km/h	Saturday: Mostly clear and warm, with a high of 85°F29°C and morning low of 68°F20°C. Breezy from the SSW at 5 to 7 mph8 to 11 km/h. Dry air. Saturday Night: Mostly clear, with a low around 62°F17°C. Light wind from the WSW around 2 mph3 km/h.
Showers	High 82°F28°C	Low 67°F20°C	Precip 0.11 in2.9 mm27%	Cloud 26%	Wind SW 3 mph5 km/h	Sunday: Partly cloudy and warm, with a high of 82°F28°C and morning low of 69°F21°C. Light wind from the SW around 4 mph7 km/h. 27% chance of showers throughout the day. Sunday Night: Mostly clear, with a low around 67°F20°C. Light wind from the WSW around 2 mph3 km/h. 23% chance of drizzle throughout the night.
Clear	High 86°F30°C	Low 63°F17°C	Precip 0 in0 mm—	Cloud 13%	Wind SW 3 mph5 km/h	Monday: Mostly clear and warm, with a high of 86°F30°C and morning low of 69°F21°C. Breezy from the SW at 5 to 7 mph8 to 11 km/h. Monday Night: Mostly clear, with a low around 63°F17°C. Light wind from the SSW around 2 mph3 km/h.
Clear	High 88°F31°C	Low 64°F18°C	Precip 0 in0.1 mm2%	Cloud 22%	Wind SW 3 mph5 km/h	Tuesday: Mostly clear and hot, with a high of 88°F31°C and morning low of 69°F20°C. Light wind from the SW around 4 mph7 km/h. Dry air. Tuesday Night: Mostly clear, with a low around 64°F18°C. Light wind from the N around 2 mph3 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	WednesdaySep 2	80°F27°C	66°F19°C	0 in0 mm· —	0%	Clear	SW 5 mph8 km/h
DayMostly clear and warm, with a high of 80°F27°C and morning low of 76°F24°C. Breezy from the SW at 7 to 8 mph11 to 12 km/h. Dry air. NightMostly clear, with a low around 66°F19°C. Light wind from the SW around 3 mph4 km/h.
	ThursdaySep 3	80°F27°C	61°F16°C	0 in0 mm· —	3%	Clear	SSW 4 mph6 km/h
DayMostly clear and warm, with a high of 80°F27°C and morning low of 66°F19°C. Breezy from the SSW at 5 to 8 mph9 to 12 km/h. NightMostly clear, with a low around 61°F16°C. Light wind from the SSW around 2 mph4 km/h.
	FridaySep 4	81°F27°C	62°F17°C	0 in0 mm· —	12%	Clear	SSW 3 mph6 km/h
DayMostly clear and warm, with a high of 81°F27°C and morning low of 65°F19°C. Breezy from the SSW at 5 to 7 mph8 to 11 km/h. NightMostly clear, with a low around 62°F17°C. Light wind from the SSW around 2 mph3 km/h.
	SaturdaySep 5	85°F29°C	62°F17°C	0 in0.1 mm· 4%	8%	Clear	SSW 3 mph5 km/h
DayMostly clear and warm, with a high of 85°F29°C and morning low of 68°F20°C. Breezy from the SSW at 5 to 7 mph8 to 11 km/h. Dry air. NightMostly clear, with a low around 62°F17°C. Light wind from the WSW around 2 mph3 km/h.
	SundaySep 6	82°F28°C	67°F20°C	0.11 in2.9 mm· 27%	26%	Showers	SW 3 mph5 km/h
DayPartly cloudy and warm, with a high of 82°F28°C and morning low of 69°F21°C. Light wind from the SW around 4 mph7 km/h. 27% chance of showers throughout the day. NightMostly clear, with a low around 67°F20°C. Light wind from the WSW around 2 mph3 km/h. 23% chance of drizzle throughout the night.
	MondaySep 7	86°F30°C	63°F17°C	0 in0 mm· —	13%	Clear	SW 3 mph5 km/h
DayMostly clear and warm, with a high of 86°F30°C and morning low of 69°F21°C. Breezy from the SW at 5 to 7 mph8 to 11 km/h. NightMostly clear, with a low around 63°F17°C. Light wind from the SSW around 2 mph3 km/h.
	TuesdaySep 8	88°F31°C	64°F18°C	0 in0.1 mm· 2%	22%	Clear	SW 3 mph5 km/h
DayMostly clear and hot, with a high of 88°F31°C and morning low of 69°F20°C. Light wind from the SW around 4 mph7 km/h. Dry air. NightMostly clear, with a low around 64°F18°C. Light wind from the N around 2 mph3 km/h.
	WednesdaySep 9	88°F31°C	66°F19°C	0.01 in0.2 mm· 4%	23%	Clear	SW 3 mph5 km/h
DayMostly clear and hot, with a high of 88°F31°C and morning low of 72°F22°C. Light wind from the SW around 5 mph7 km/h. NightMostly clear, with a low around 66°F19°C. Light wind from the SSW around 2 mph3 km/h.
	ThursdaySep 10	87°F31°C	68°F20°C	0.02 in0.4 mm· 4%	21%	Clear	SW 3 mph5 km/h
DayMostly clear and hot, with a high of 87°F31°C and morning low of 72°F22°C. Breezy from the SW at 5 to 7 mph8 to 11 km/h. NightMostly clear, with a low around 68°F20°C. Light wind from the SSW around 2 mph3 km/h.
	FridaySep 11	85°F30°C	66°F19°C	0.03 in0.7 mm· 4%	20%	Clear	SW 3 mph6 km/h
DayMostly clear and warm, with a high of 85°F30°C and morning low of 71°F22°C. Breezy from the SW at 5 to 7 mph8 to 12 km/h. NightMostly clear, with a low around 66°F19°C. Light wind from the SSW around 2 mph3 km/h.
	SaturdaySep 12	83°F28°C	66°F19°C	0.04 in1 mm· 6%	32%	Clear	SSW 4 mph6 km/h
DayPartly cloudy and warm, with a high of 83°F28°C and morning low of 69°F21°C. Breezy from the SSW at 5 to 7 mph8 to 11 km/h. NightPartly cloudy, with a low around 66°F19°C. Light wind from the SSW around 2 mph4 km/h.
	SundaySep 13	81°F27°C	65°F19°C	0.1 in2.6 mm· 13%	37%	Showers	SSW 4 mph6 km/h
DayPartly cloudy and warm, with a high of 81°F27°C and morning low of 69°F21°C. Breezy from the SSW at 5 to 7 mph8 to 11 km/h. 13% chance of showers throughout the day. NightPartly cloudy, with a low around 65°F19°C. Light wind from the SSW around 2 mph4 km/h. 11% chance of drizzle throughout the night.
	MondaySep 14	83°F29°C	65°F18°C	0.07 in1.8 mm· 10%	30%	Drizzle	SW 3 mph5 km/h
DayPartly cloudy and warm, with a high of 83°F29°C and morning low of 68°F20°C. Light wind from the SW around 5 mph7 km/h. 10% chance of drizzle throughout the day. NightPartly cloudy, with a low around 65°F18°C. Light wind from the SW around 2 mph3 km/h.
	TuesdaySep 15	86°F30°C	66°F19°C	0.08 in2 mm· 8%	22%	Clear	SW 3 mph5 km/h
DayMostly clear and warm, with a high of 86°F30°C and morning low of 69°F21°C. Light wind from the SW around 5 mph7 km/h. NightMostly clear, with a low around 66°F19°C. Light wind from the SW around 2 mph3 km/h.
	WednesdaySep 16	87°F31°C	66°F19°C	0.03 in0.7 mm· 4%	23%	Clear	SW 3 mph5 km/h
DayMostly clear and hot, with a high of 87°F31°C and morning low of 70°F21°C. Breezy from the SW at 4 to 7 mph7 to 11 km/h. NightMostly clear, with a low around 66°F19°C. Light wind from the SW around 2 mph3 km/h.

Nearby Cities

Walnut3 mi5 km Pomona4 mi6 km Chino Hills4 mi6 km San Dimas5 mi9 km South San Jose Hills6 mi9 km La Verne6 mi9 km

About This Forecast

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Coordinates: 34.0286°N, 117.8103°W·Elevation: 212m·Timezone: America/Los_Angeles·Population: 56,897