Current Conditions

Diamond Bar, California

91°F33°C

Drizzle

Wind

WNW 6 mph10 km/h

Humidity

39%

Cloud Cover

35%

As of Tuesday, September 8, 2026 at 4:01 PM PDT

Today's Outlook

Day

Mostly cloudy and hot, with a high of 91°F33°C and morning low of 87°F30°C. Light wind from the W around 4 mph7 km/h. 15% chance of drizzle in the afternoon.

Night

Mostly clear, with a low around 79°F26°C. Light wind from the N around 3 mph5 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Drizzle	High 91°F33°C	Low 79°F26°C	Precip 0.01 in0.2 mm15%	Cloud 41%	Wind WNW 4 mph6 km/h	Tuesday: Mostly cloudy and hot, with a high of 91°F33°C and morning low of 87°F30°C. Light wind from the W around 4 mph7 km/h. 15% chance of drizzle in the afternoon. Tuesday Night: Mostly clear, with a low around 79°F26°C. Light wind from the N around 3 mph5 km/h.
Drizzle	High 100°F38°C	Low 75°F24°C	Precip 0.01 in0.3 mm23%	Cloud 24%	Wind NW 3 mph5 km/h	Wednesday: Mostly clear and hot, with a high of 100°F38°C and morning low of 80°F27°C. Light wind from the W around 4 mph6 km/h. 23% chance of drizzle in the afternoon. Heat risk in the afternoon. Wednesday Night: Partly cloudy, with a low around 75°F24°C. Light wind from the NNE around 3 mph4 km/h.
Clear	High 94°F34°C	Low 77°F25°C	Precip 0 in0.1 mm5%	Cloud 19%	Wind SSW 4 mph6 km/h	Thursday: Mostly clear and hot, with a high of 94°F34°C and morning low of 81°F27°C. Breezy from the SW at 5 to 7 mph8 to 11 km/h. Humid. Thursday Night: Mostly clear, with a low around 77°F25°C. Light wind from the SSE around 2 mph4 km/h.
Clear	High 89°F32°C	Low 73°F23°C	Precip 0 in0 mm—	Cloud 4%	Wind SSW 3 mph5 km/h	Friday: Mostly clear and hot, with a high of 89°F32°C and morning low of 77°F25°C. Light wind from the SSW around 5 mph8 km/h. Humid. Friday Night: Mostly clear, with a low around 73°F23°C. Light wind from the S around 2 mph3 km/h.
Clear	High 86°F30°C	Low 71°F21°C	Precip 0 in0 mm—	Cloud 8%	Wind SSW 3 mph5 km/h	Saturday: Mostly clear and hot, with a high of 86°F30°C and morning low of 74°F23°C. Light wind from the SW around 4 mph7 km/h. Saturday Night: Mostly clear, with a low around 71°F21°C. Light wind from the SSW around 2 mph3 km/h.
Clear	High 87°F31°C	Low 68°F20°C	Precip 0 in0 mm—	Cloud 12%	Wind SW 3 mph5 km/h	Sunday: Mostly clear and hot, with a high of 87°F31°C and morning low of 72°F22°C. Light wind from the SW around 4 mph7 km/h. Sunday Night: Mostly clear, with a low around 68°F20°C. Light wind from the SSW around 2 mph3 km/h.
Clear	High 86°F30°C	Low 68°F20°C	Precip 0 in0 mm—	Cloud 10%	Wind SSW 3 mph5 km/h	Monday: Mostly clear and hot, with a high of 86°F30°C and morning low of 72°F22°C. Light wind from the SSW around 5 mph7 km/h. Monday Night: Mostly clear, with a low around 68°F20°C. Light wind from the S around 2 mph3 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	TuesdaySep 8	91°F33°C	79°F26°C	0.01 in0.2 mm· 15%	41%	Drizzle	WNW 4 mph6 km/h
DayMostly cloudy and hot, with a high of 91°F33°C and morning low of 87°F30°C. Light wind from the W around 4 mph7 km/h. 15% chance of drizzle in the afternoon. NightMostly clear, with a low around 79°F26°C. Light wind from the N around 3 mph5 km/h.
	WednesdaySep 9	100°F38°C	75°F24°C	0.01 in0.3 mm· 23%	24%	Drizzle	NW 3 mph5 km/h
DayMostly clear and hot, with a high of 100°F38°C and morning low of 80°F27°C. Light wind from the W around 4 mph6 km/h. 23% chance of drizzle in the afternoon. Heat risk in the afternoon. NightPartly cloudy, with a low around 75°F24°C. Light wind from the NNE around 3 mph4 km/h.
	ThursdaySep 10	94°F34°C	77°F25°C	0 in0.1 mm· 5%	19%	Clear	SSW 4 mph6 km/h
DayMostly clear and hot, with a high of 94°F34°C and morning low of 81°F27°C. Breezy from the SW at 5 to 7 mph8 to 11 km/h. Humid. NightMostly clear, with a low around 77°F25°C. Light wind from the SSE around 2 mph4 km/h.
	FridaySep 11	89°F32°C	73°F23°C	0 in0 mm· —	4%	Clear	SSW 3 mph5 km/h
DayMostly clear and hot, with a high of 89°F32°C and morning low of 77°F25°C. Light wind from the SSW around 5 mph8 km/h. Humid. NightMostly clear, with a low around 73°F23°C. Light wind from the S around 2 mph3 km/h.
	SaturdaySep 12	86°F30°C	71°F21°C	0 in0 mm· —	8%	Clear	SSW 3 mph5 km/h
DayMostly clear and hot, with a high of 86°F30°C and morning low of 74°F23°C. Light wind from the SW around 4 mph7 km/h. NightMostly clear, with a low around 71°F21°C. Light wind from the SSW around 2 mph3 km/h.
	SundaySep 13	87°F31°C	68°F20°C	0 in0 mm· —	12%	Clear	SW 3 mph5 km/h
DayMostly clear and hot, with a high of 87°F31°C and morning low of 72°F22°C. Light wind from the SW around 4 mph7 km/h. NightMostly clear, with a low around 68°F20°C. Light wind from the SSW around 2 mph3 km/h.
	MondaySep 14	86°F30°C	68°F20°C	0 in0 mm· —	10%	Clear	SSW 3 mph5 km/h
DayMostly clear and hot, with a high of 86°F30°C and morning low of 72°F22°C. Light wind from the SSW around 5 mph7 km/h. NightMostly clear, with a low around 68°F20°C. Light wind from the S around 2 mph3 km/h.
	TuesdaySep 15	84°F29°C	67°F19°C	0 in0 mm· —	15%	Clear	SSW 3 mph5 km/h
DayMostly clear and warm, with a high of 84°F29°C and morning low of 71°F21°C. Light wind from the SSW around 4 mph7 km/h. NightMostly clear, with a low around 67°F19°C. Light wind from the SSW around 2 mph3 km/h.
	WednesdaySep 16	84°F29°C	66°F19°C	0.01 in0.3 mm· 3%	20%	Clear	SW 3 mph5 km/h
DayMostly clear and warm, with a high of 84°F29°C and morning low of 69°F21°C. Light wind from the SW around 4 mph7 km/h. NightMostly clear, with a low around 66°F19°C. Light wind from the SW around 2 mph3 km/h.
	ThursdaySep 17	84°F29°C	65°F18°C	0.01 in0.3 mm· 3%	21%	Clear	SW 3 mph5 km/h
DayMostly clear and warm, with a high of 84°F29°C and morning low of 70°F21°C. Light wind from the SW around 4 mph7 km/h. NightMostly clear, with a low around 65°F18°C. Light wind from the SW around 2 mph3 km/h.
	FridaySep 18	87°F30°C	65°F18°C	0.01 in0.3 mm· 2%	24%	Clear	SW 3 mph5 km/h
DayPartly cloudy and hot, with a high of 87°F30°C and morning low of 69°F21°C. Light wind from the SW around 4 mph7 km/h. NightMostly clear, with a low around 65°F18°C. Light wind from the WSW around 2 mph3 km/h.
	SaturdaySep 19	88°F31°C	66°F19°C	0 in0.1 mm· 2%	26%	Clear	SW 3 mph5 km/h
DayPartly cloudy and hot, with a high of 88°F31°C and morning low of 71°F22°C. Light wind from the SW around 4 mph7 km/h. NightPartly cloudy, with a low around 66°F19°C. Light wind from the SW around 2 mph3 km/h.
	SundaySep 20	87°F31°C	67°F19°C	0 in0.1 mm· 2%	31%	Clear	SW 3 mph5 km/h
DayPartly cloudy and hot, with a high of 87°F31°C and morning low of 70°F21°C. Light wind from the SW around 4 mph7 km/h. NightPartly cloudy, with a low around 67°F19°C. Light wind from the SSW around 2 mph3 km/h.
	MondaySep 21	85°F30°C	66°F19°C	0.04 in1 mm· 3%	31%	Clear	SW 3 mph5 km/h
DayPartly cloudy and warm, with a high of 85°F30°C and morning low of 69°F21°C. Light wind from the SW around 5 mph7 km/h. NightPartly cloudy, with a low around 66°F19°C. Light wind from the SSW around 2 mph3 km/h.
	TuesdaySep 22	86°F30°C	65°F19°C	0.04 in0.9 mm· 7%	30%	Clear	SW 3 mph5 km/h
DayPartly cloudy 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. NightPartly cloudy, with a low around 65°F19°C. Light wind from the SSW 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