Current Conditions

Union City, California

61°F16°C

Clear

Wind

SW 6 mph9 km/h

Humidity

84%

Cloud Cover

39%

As of Monday, September 21, 2026 at 8:47 PM PDT

Today's Outlook

Night

Partly cloudy, with a low around 57°F14°C. Light wind from the SW around 4 mph6 km/h.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Clear	High 71°F22°C	Low 57°F14°C	Precip 0 in0 mm—	Cloud 38%	Wind SW 5 mph8 km/h	Tuesday: Partly cloudy and warm, with a high of 71°F22°C and morning low of 59°F15°C. Light wind from the WSW around 5 mph9 km/h. Tuesday Night: Partly cloudy, with a low around 57°F14°C. Light wind from the SW around 4 mph6 km/h.
Clear	High 82°F28°C	Low 57°F14°C	Precip 0 in0 mm—	Cloud 30%	Wind W 3 mph5 km/h	Wednesday: Partly cloudy and warm, with a high of 82°F28°C and morning low of 59°F15°C. Light wind from the NW around 3 mph5 km/h. Wednesday Night: Partly cloudy, with a low around 57°F14°C. Light wind from the SSW around 3 mph5 km/h.
Partly Cloudy	High 83°F28°C	Low 60°F16°C	Precip 0 in0 mm—	Cloud 47%	Wind SW 4 mph7 km/h	Thursday: Partly cloudy and warm, with a high of 83°F28°C and morning low of 61°F16°C. Breezy from the WSW at 5 to 7 mph8 to 11 km/h. Thursday Night: Mostly cloudy, with a low around 60°F16°C. Light wind from the SSW around 3 mph6 km/h.
Clear	High 76°F24°C	Low 58°F14°C	Precip 0 in0 mm—	Cloud 33%	Wind WSW 5 mph8 km/h	Friday: Partly cloudy and warm, with a high of 76°F24°C and morning low of 60°F16°C. Breezy from the W at 6 to 8 mph10 to 13 km/h. Friday Night: Partly cloudy, with a low around 58°F14°C. Light wind from the SW around 3 mph5 km/h.
Clear	High 77°F25°C	Low 55°F13°C	Precip 0 in0 mm—	Cloud 32%	Wind WSW 4 mph6 km/h	Saturday: Partly cloudy and warm, with a high of 77°F25°C and morning low of 58°F14°C. Light wind from the WSW around 4 mph7 km/h. Dry air. Saturday Night: Partly cloudy, with a low around 55°F13°C. Light wind from the SW around 3 mph5 km/h.
Partly Cloudy	High 74°F23°C	Low 55°F13°C	Precip 0 in0 mm—	Cloud 42%	Wind WSW 5 mph7 km/h	Sunday: Partly cloudy and warm, with a high of 74°F23°C and morning low of 57°F14°C. Breezy from the WSW at 6 to 7 mph9 to 11 km/h. Dry air. Sunday Night: Partly cloudy, with a low around 55°F13°C. Light wind from the SW around 4 mph6 km/h.
Clear	High 76°F24°C	Low 56°F13°C	Precip 0.01 in0.3 mm3%	Cloud 29%	Wind WSW 4 mph6 km/h	Monday: Partly cloudy and warm, with a high of 76°F24°C and morning low of 58°F15°C. Light wind from the W around 5 mph8 km/h. Monday Night: Partly cloudy, with a low around 56°F13°C. Light wind from the SW around 3 mph5 km/h.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	TuesdaySep 22	71°F22°C	57°F14°C	0 in0 mm· —	38%	Clear	SW 5 mph8 km/h
DayPartly cloudy and warm, with a high of 71°F22°C and morning low of 59°F15°C. Light wind from the WSW around 5 mph9 km/h. NightPartly cloudy, with a low around 57°F14°C. Light wind from the SW around 4 mph6 km/h.
	WednesdaySep 23	82°F28°C	57°F14°C	0 in0 mm· —	30%	Clear	W 3 mph5 km/h
DayPartly cloudy and warm, with a high of 82°F28°C and morning low of 59°F15°C. Light wind from the NW around 3 mph5 km/h. NightPartly cloudy, with a low around 57°F14°C. Light wind from the SSW around 3 mph5 km/h.
	ThursdaySep 24	83°F28°C	60°F16°C	0 in0 mm· —	47%	Partly Cloudy	SW 4 mph7 km/h
DayPartly cloudy and warm, with a high of 83°F28°C and morning low of 61°F16°C. Breezy from the WSW at 5 to 7 mph8 to 11 km/h. NightMostly cloudy, with a low around 60°F16°C. Light wind from the SSW around 3 mph6 km/h.
	FridaySep 25	76°F24°C	58°F14°C	0 in0 mm· —	33%	Clear	WSW 5 mph8 km/h
DayPartly cloudy and warm, with a high of 76°F24°C and morning low of 60°F16°C. Breezy from the W at 6 to 8 mph10 to 13 km/h. NightPartly cloudy, with a low around 58°F14°C. Light wind from the SW around 3 mph5 km/h.
	SaturdaySep 26	77°F25°C	55°F13°C	0 in0 mm· —	32%	Clear	WSW 4 mph6 km/h
DayPartly cloudy and warm, with a high of 77°F25°C and morning low of 58°F14°C. Light wind from the WSW around 4 mph7 km/h. Dry air. NightPartly cloudy, with a low around 55°F13°C. Light wind from the SW around 3 mph5 km/h.
	SundaySep 27	74°F23°C	55°F13°C	0 in0 mm· —	42%	Partly Cloudy	WSW 5 mph7 km/h
DayPartly cloudy and warm, with a high of 74°F23°C and morning low of 57°F14°C. Breezy from the WSW at 6 to 7 mph9 to 11 km/h. Dry air. NightPartly cloudy, with a low around 55°F13°C. Light wind from the SW around 4 mph6 km/h.
	MondaySep 28	76°F24°C	56°F13°C	0.01 in0.3 mm· 3%	29%	Clear	WSW 4 mph6 km/h
DayPartly cloudy and warm, with a high of 76°F24°C and morning low of 58°F15°C. Light wind from the W around 5 mph8 km/h. NightPartly cloudy, with a low around 56°F13°C. Light wind from the SW around 3 mph5 km/h.
	TuesdaySep 29	78°F26°C	57°F14°C	0.02 in0.4 mm· 6%	27%	Clear	WSW 4 mph6 km/h
DayPartly cloudy and warm, with a high of 78°F26°C and morning low of 59°F15°C. Light wind from the W around 4 mph7 km/h. NightPartly cloudy, with a low around 57°F14°C. Light wind from the SW around 3 mph5 km/h.
	WednesdaySep 30	78°F26°C	58°F15°C	0.05 in1.2 mm· 6%	32%	Clear	WSW 4 mph7 km/h
DayPartly cloudy and warm, with a high of 78°F26°C and morning low of 59°F15°C. Light wind from the W around 5 mph8 km/h. NightPartly cloudy, with a low around 58°F15°C. Light wind from the SW around 3 mph5 km/h.
	ThursdayOct 1	76°F24°C	58°F15°C	0.03 in0.7 mm· 7%	40%	Partly Cloudy	WSW 4 mph7 km/h
DayPartly cloudy and warm, with a high of 76°F24°C and morning low of 59°F15°C. Breezy from the W at 5 to 7 mph9 to 11 km/h. NightPartly cloudy, with a low around 58°F15°C. Light wind from the SW around 4 mph6 km/h.
	FridayOct 2	76°F24°C	57°F14°C	0.05 in1.2 mm· 9%	26%	Clear	W 5 mph7 km/h
DayPartly cloudy and warm, with a high of 76°F24°C and morning low of 58°F15°C. Breezy from the WNW at 6 to 7 mph9 to 11 km/h. Dry air. NightPartly cloudy, with a low around 57°F14°C. Light wind from the WSW around 4 mph6 km/h.
	SaturdayOct 3	78°F25°C	58°F14°C	0.05 in1.2 mm· 9%	24%	Clear	W 4 mph7 km/h
DayMostly clear and warm, with a high of 78°F25°C and morning low of 59°F15°C. Light wind from the WNW around 5 mph8 km/h. Dry air. NightMostly clear, with a low around 58°F14°C. Light wind from the SW around 4 mph6 km/h.
	SundayOct 4	78°F25°C	58°F14°C	0.01 in0.3 mm· 4%	26%	Clear	WSW 4 mph6 km/h
DayPartly cloudy and warm, with a high of 78°F25°C and morning low of 59°F15°C. Light wind from the W around 5 mph7 km/h. NightPartly cloudy, with a low around 58°F14°C. Light wind from the SW around 3 mph6 km/h.
	MondayOct 5	77°F25°C	58°F15°C	0.01 in0.3 mm· 3%	26%	Clear	WSW 4 mph7 km/h
DayPartly cloudy and warm, with a high of 77°F25°C and morning low of 60°F15°C. Light wind from the W around 5 mph8 km/h. NightPartly cloudy, with a low around 58°F15°C. Light wind from the SW around 3 mph5 km/h.
	TuesdayOct 6	78°F25°C	58°F15°C	0.01 in0.3 mm· 4%	27%	Clear	W 4 mph7 km/h
DayMostly clear and warm, with a high of 78°F25°C and morning low of 59°F15°C. Light wind from the WNW around 5 mph8 km/h. NightPartly cloudy, with a low around 58°F15°C. Light wind from the S around 3 mph5 km/h.

Nearby Cities

Fremont4 mi6 km Newark5 mi8 km Hayward6 mi10 km Castro Valley8 mi12 km San Lorenzo8 mi13 km Ashland9 mi14 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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Coordinates: 37.5958°N, 122.0191°W·Elevation: 21m·Timezone: America/Los_Angeles·Population: 74,494