Current Conditions

Ontario, California

74°F23°C

Cloudy

Wind

SW 5 mph8 km/h

Humidity

63%

Cloud Cover

40%

As of Wednesday, August 12, 2026 at 8:57 PM PDT

Today's Outlook

Night

Mostly cloudy, with a low around 66°F19°C. Light wind from the SW around 3 mph5 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Cloudy	High 81°F27°C	Low 66°F19°C	Precip 0 in0 mm—	Cloud 82%	Wind SSW 4 mph7 km/h	Thursday: Overcast and warm, with a high of 81°F27°C and morning low of 69°F20°C. Breezy from the SSW at 5 to 7 mph8 to 11 km/h. Thursday Night: Mostly cloudy, with a low around 66°F19°C. Light wind from the SW around 3 mph5 km/h.
Clear	High 84°F29°C	Low 66°F19°C	Precip 0 in0.1 mm1%	Cloud 16%	Wind SW 4 mph6 km/h	Friday: Mostly clear and warm, with a high of 84°F29°C and morning low of 68°F20°C. Breezy from the SSW at 5 to 7 mph8 to 12 km/h. Friday Night: Mostly clear, with a low around 66°F19°C. Light wind from the SW around 3 mph4 km/h.
Clear	High 86°F30°C	Low 64°F18°C	Precip 0 in0 mm—	Cloud 7%	Wind SW 3 mph5 km/h	Saturday: Mostly clear and warm, with a high of 86°F30°C and morning low of 70°F21°C. Light wind from the SW around 4 mph7 km/h. Saturday Night: Mostly clear, with a low around 64°F18°C. Light wind from the SW around 2 mph3 km/h.
Clear	High 90°F32°C	Low 66°F19°C	Precip 0 in0 mm—	Cloud 24%	Wind SW 3 mph5 km/h	Sunday: Mostly clear and hot, with a high of 90°F32°C and morning low of 71°F22°C. Breezy from the SW at 4 to 7 mph7 to 11 km/h. Sunday Night: Partly cloudy, with a low around 66°F19°C. Light wind from the SW around 2 mph3 km/h.
Partly Cloudy	High 90°F32°C	Low 67°F20°C	Precip 0 in0 mm—	Cloud 41%	Wind SW 3 mph5 km/h	Monday: Partly cloudy and hot, with a high of 90°F32°C and morning low of 73°F23°C. Breezy from the SW at 5 to 7 mph8 to 11 km/h. Monday Night: Partly cloudy, with a low around 67°F20°C. Light wind from the SW around 2 mph3 km/h.
Clear	High 90°F32°C	Low 68°F20°C	Precip 0 in0 mm—	Cloud 28%	Wind SW 3 mph5 km/h	Tuesday: Partly cloudy and hot, with a high of 90°F32°C and morning low of 73°F23°C. Breezy from the SW at 5 to 7 mph8 to 11 km/h. Tuesday Night: Partly cloudy, with a low around 68°F20°C. Light wind from the SW around 2 mph3 km/h.
Clear	High 91°F33°C	Low 68°F20°C	Precip 0 in0 mm—	Cloud 19%	Wind SW 3 mph5 km/h	Wednesday: Mostly clear and hot, with a high of 91°F33°C and morning low of 74°F23°C. Light wind from the SW around 5 mph8 km/h. Wednesday Night: Mostly clear, with a low around 68°F20°C. Light wind from the SW around 2 mph3 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	ThursdayAug 13	81°F27°C	66°F19°C	0 in0 mm· —	82%	Cloudy	SSW 4 mph7 km/h
DayOvercast and warm, with a high of 81°F27°C and morning low of 69°F20°C. Breezy from the SSW at 5 to 7 mph8 to 11 km/h. NightMostly cloudy, with a low around 66°F19°C. Light wind from the SW around 3 mph5 km/h.
	FridayAug 14	84°F29°C	66°F19°C	0 in0.1 mm· 1%	16%	Clear	SW 4 mph6 km/h
DayMostly clear and warm, with a high of 84°F29°C and morning low of 68°F20°C. Breezy from the SSW at 5 to 7 mph8 to 12 km/h. NightMostly clear, with a low around 66°F19°C. Light wind from the SW around 3 mph4 km/h.
	SaturdayAug 15	86°F30°C	64°F18°C	0 in0 mm· —	7%	Clear	SW 3 mph5 km/h
DayMostly clear and warm, with a high of 86°F30°C and morning low of 70°F21°C. Light wind from the SW around 4 mph7 km/h. NightMostly clear, with a low around 64°F18°C. Light wind from the SW around 2 mph3 km/h.
	SundayAug 16	90°F32°C	66°F19°C	0 in0 mm· —	24%	Clear	SW 3 mph5 km/h
DayMostly clear and hot, with a high of 90°F32°C and morning low of 71°F22°C. Breezy from the SW at 4 to 7 mph7 to 11 km/h. NightPartly cloudy, with a low around 66°F19°C. Light wind from the SW around 2 mph3 km/h.
	MondayAug 17	90°F32°C	67°F20°C	0 in0 mm· —	41%	Partly Cloudy	SW 3 mph5 km/h
DayPartly cloudy and hot, with a high of 90°F32°C and morning low of 73°F23°C. Breezy from the SW at 5 to 7 mph8 to 11 km/h. NightPartly cloudy, with a low around 67°F20°C. Light wind from the SW around 2 mph3 km/h.
	TuesdayAug 18	90°F32°C	68°F20°C	0 in0 mm· —	28%	Clear	SW 3 mph5 km/h
DayPartly cloudy and hot, with a high of 90°F32°C and morning low of 73°F23°C. Breezy from the SW at 5 to 7 mph8 to 11 km/h. NightPartly cloudy, with a low around 68°F20°C. Light wind from the SW around 2 mph3 km/h.
	WednesdayAug 19	91°F33°C	68°F20°C	0 in0 mm· —	19%	Clear	SW 3 mph5 km/h
DayMostly clear and hot, with a high of 91°F33°C and morning low of 74°F23°C. Light wind from the SW around 5 mph8 km/h. NightMostly clear, with a low around 68°F20°C. Light wind from the SW around 2 mph3 km/h.
	ThursdayAug 20	91°F33°C	68°F20°C	0 in0 mm· —	15%	Clear	SW 3 mph5 km/h
DayMostly clear and hot, with a high of 91°F33°C and morning low of 73°F23°C. Light wind from the SW around 5 mph7 km/h. NightMostly clear, with a low around 68°F20°C. Light wind from the SW around 2 mph3 km/h.
	FridayAug 21	92°F33°C	68°F20°C	0 in0.1 mm· 3%	19%	Clear	SW 3 mph5 km/h
DayMostly clear and hot, with a high of 92°F33°C and morning low of 74°F23°C. Light wind from the SW around 5 mph7 km/h. NightMostly clear, with a low around 68°F20°C. Light wind from the SW around 2 mph3 km/h.
	SaturdayAug 22	93°F34°C	69°F21°C	0 in0 mm· —	20%	Clear	SW 3 mph5 km/h
DayMostly clear and hot, with a high of 93°F34°C and morning low of 75°F24°C. Light wind from the SW around 4 mph7 km/h. NightMostly clear, with a low around 69°F21°C. Light wind from the SW around 2 mph3 km/h.
	SundayAug 23	92°F34°C	70°F21°C	0 in0.1 mm· 7%	19%	Clear	SW 3 mph5 km/h
DayMostly clear and hot, with a high of 92°F34°C and morning low of 75°F24°C. Light wind from the SW around 4 mph7 km/h. NightMostly clear, with a low around 70°F21°C. Light wind from the SW around 2 mph3 km/h.
	MondayAug 24	92°F33°C	70°F21°C	0.01 in0.3 mm· 6%	22%	Clear	SW 3 mph5 km/h
DayMostly clear and hot, with a high of 92°F33°C and morning low of 76°F24°C. Light wind from the SW around 4 mph7 km/h. NightMostly clear, with a low around 70°F21°C. Light wind from the SW around 2 mph3 km/h.
	TuesdayAug 25	91°F33°C	69°F21°C	0.01 in0.3 mm· 8%	25%	Clear	SW 3 mph5 km/h
DayPartly cloudy and hot, with a high of 91°F33°C and morning low of 74°F23°C. Light wind from the SW around 4 mph7 km/h. NightMostly clear, with a low around 69°F21°C. Light wind from the SW around 2 mph3 km/h.
	WednesdayAug 26	91°F33°C	69°F20°C	0.01 in0.3 mm· 9%	28%	Clear	SW 3 mph5 km/h
DayPartly cloudy and hot, with a high of 91°F33°C and morning low of 76°F24°C. Light wind from the SW around 4 mph7 km/h. NightPartly cloudy, with a low around 69°F20°C. Light wind from the SW around 2 mph3 km/h.
	ThursdayAug 27	90°F32°C	69°F21°C	0.06 in1.4 mm· 8%	37%	Clear	SW 3 mph6 km/h
DayPartly cloudy and hot, with a high of 90°F32°C and morning low of 74°F23°C. Light wind from the SW around 4 mph7 km/h. NightPartly cloudy, with a low around 69°F21°C. Light wind from the NNW around 1 mph2 km/h.

Nearby Cities

Upland2 mi4 km Montclair2 mi4 km Chino4 mi7 km Rancho Cucamonga4 mi7 km Claremont5 mi7 km Pomona6 mi9 km

About This Forecast

This forecast is powered by WeatherMesh, the world's most advanced and accurate weather model powered by AI. WeatherMesh is built on proprietary data from WindBorne's Global Sounding Balloon constellation — the world's largest fleet of autonomous, long-duration weather balloons — collecting observations across 100% of Earth, including over oceans and remote regions where no other data exists.

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How to Access Weather Forecasts

Pattern	Example	Description
/weather/{country}/{city}/	/weather/united-states/san-francisco/	City forecast (canonical URL)
/weather/{city}/	/weather/tokyo/	Shorthand — redirects to most populous match
/weather/{country}/{region}/{city}/	/weather/united-states/california/san-francisco/	With region — redirects to canonical
/weather/nearby?lat={lat}&lon={lon}	/weather/nearby?lat=48.1&lon=11.5	Find nearest city by coordinates
/weather/{country}/	/weather/germany/	Country index — all cities by region

Country and city names use lowercase slugs with hyphens (e.g. united-states, san-francisco). Arbitrary city names are supported — if not in our database, we geocode the name and serve the forecast for that location.

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Coordinates: 34.0633°N, 117.6509°W·Elevation: 306m·Timezone: America/Los_Angeles·Population: 171,214