Climate and monthly weather forecast
Union City, CA

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Weather in January

January, like December, is a moderate winter month in Union City, California, with an average temperature ranging between min 44.2°F (6.8°C) and max 57.6°F (14.2°C). Union City's weather in January indicates an average high-temperature of a still moderate 57.6°F (14.2°C), nearly consistent with the 56.3°F (13.5°C) of December. Weather in January »

Weather in February

February, the last month of the winter in Union City, is also a moderate month, with an average temperature fluctuating between 59.7°F (15.4°C) and 44.2°F (6.8°C). February's arrival brings an average high-temperature of a still moderate 59.7°F (15.4°C), demonstrating subtle variation from the preceding month. Weather in February »

Weather in March

March, the first month of the spring in Union City, is a comfortable month, with an average temperature varying between 62.2°F (16.8°C) and 45°F (7.2°C). Entering March, Union City's average high-temperature reads a comfortable 62.2°F (16.8°C), indicating a close resemblance to the previous month's climate. Weather in March »

Weather in April

April, the same as March, is another enjoyable spring month in Union City, California, with an average temperature ranging between min 46.6°F (8.1°C) and max 65.8°F (18.8°C). With the transition into April, Union City notes an average high-temperature of a still comfortable 65.8°F (18.8°C), closely resembling March. Weather in April »

Weather in May

The last month of the spring, May, is a pleasant month in Union City, California, with an average temperature ranging between min 49.5°F (9.7°C) and max 69.8°F (21°C). Union City experiences an average high-temperature of an agreeable 69.8°F (21°C) with the onset of May, subtly varied from April's 65.8°F (18.8°C). Weather in May »

Weather in June

The first month of the summer, June, is a moderately hot month in Union City, California, with an average temperature varying between 53.8°F (12.1°C) and 76.8°F (24.9°C). The onset of June brings a minor temperature shift, with the average high-temperature moving from an agreeable 69.8°F (21°C) in May to a warm 76.8°F (24.9°C). Weather in June »

Weather in July

July, the same as June, is a moderately hot summer month in Union City, California, with an average temperature fluctuating between 80.1°F (26.7°C) and 55.2°F (12.9°C). Union City sees its peak of temperatures during July and August, with an average high-temperature of 80.1°F (26.7°C). Weather in July »

Weather in August

The last month of the summer, August, is another warm month in Union City, California, with an average temperature fluctuating between 80.1°F (26.7°C) and 56.7°F (13.7°C). July and August represent the warmest period, with an average high-temperature of 80.1°F (26.7°C). Weather in August »

Weather in September

The first month of the autumn, September, is still a warm month in Union City, California, with an average temperature varying between 78.6°F (25.9°C) and 56.7°F (13.7°C). As September takes hold, the average high-temperature is a still warm 78.6°F (25.9°C), nearly mirroring that of the previous month. Weather in September »

Weather in October

October, the same as September, in Union City, California, is another pleasant autumn month, with an average temperature ranging between max 72.1°F (22.3°C) and min 53.8°F (12.1°C). As September shifts into October, a minor alteration in temperatures is observed, with average highs reducing from a warm 78.6°F (25.9°C) to a pleasant 72.1°F (22.3°C). Weather in October »

Weather in November

November, the last month of the autumn in Union City, is another refreshing month, with temperature in the range of an average high of 63.5°F (17.5°C) and an average low of 48.2°F (9°C). In Union City, the beginning of November is marked by a marginally lowered average high-temperature, shifting from October's agreeable 72.1°F (22.3°C) to an enjoyable 63.5°F (17.5°C). Weather in November »

Weather in December

The first month of the winter, December, is also a moderate month in Union City, California, with an average temperature ranging between max 56.3°F (13.5°C) and min 43.7°F (6.5°C). The coldest temperatures occur during December, when averages reach a peak of 56.3°F (13.5°C) and a low of 43.7°F (6.5°C). Weather in December »
Updated: Feb 9, 2024 | Published by: Weather U.S. | Resources

Frequently asked questions

How much does it rain in Union City?

In Union City, during the entire year, the rain falls for 38 days and collects up to 2.13" (54mm) of precipitation.

What are the months with the lowest UV index in Union City?

January, February, November and December, with an average maximum UV index of 3, are months with the lowest UV index.

What is the wettest month in Union City?

February is the month with the most rainfall. Rain falls for 4.4 days and accumulates 0.47" (12mm) of precipitation.

What is the most humid month in Union City?

The most humid month in Union City, California, is March, with an average relative humidity of 73%.

When is Daylight Saving Time (DST) in Union City?

On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts, and the time zone changes from PST to PDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from PDT to PST.

What is the driest month in Union City?

June through August are months without rainfall.

When are the longest days in Union City?

The month with the longest days is June, with an average of 14h and 42min of daylight.

When is the highest UV index in Union City?

June and July, with an average maximum UV index of 6, are months with the highest UV index in Union City, California.

What part of the year is the hottest in Union City?

July and August, when the average high-temperature in Union City, California, reaches 80.1°F (26.7°C), are the warmest months.

What month has the most sunshine in Union City?

The month with the most sunshine is July, with an average of 12.2h of sunshine.

What are the least humid months in Union City?

September and October, with an average relative humidity of 62%, are the least humid months.

When does it rain in Union City?

January through May, September through December are months with rainfall.

What month is the coldest in Union City?

December, known for its average high temperature of 56.3°F (13.5°C) and an average low temperature of 43.7°F (6.5°C), is the coldest month.

What is the month with the shortest days in Union City?

The month with the shortest days in Union City is December, with an average of 9h and 36min of daylight.

What is the month with the least sunshine in Union City?

December has the least sunshine of the year in Union City, California, with an average of 6h of sunshine.

Average temperature
Union City, CA

Average temperature - Union City, CA

The warmest months (with the highest average high temperature) are July and August (80.1°F).
The month with the lowest average high temperature is December (56.3°F).

The months with the highest average low temperature are August and September (56.7°F).
The coldest month (with the lowest average low temperature) is December (43.7°F).

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Average pressure
Union City, CA

Average pressure - Union City, CA

The month with the highest atmospheric pressure is January (30.13"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.92"Hg).

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Average wind speed
Union City, CA

Average wind speed - Union City, CA

The windiest month (with the highest average wind speed) is May (6.4mph).
The calmest months (with the lowest average wind speed) are October and November (4.7mph).

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Average humidity
Union City, CA

Average humidity - Union City, CA

The month with the highest relative humidity is March (73%).
The months with the lowest relative humidity are September and October (62%).

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Average rainfall
Union City, CA

Average rainfall - Union City, CA

The wettest month (with the highest rainfall) is February (0.47").
The driest months (with the least rainfall) are June, July and August (0").

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Average rainfall days
Union City, CA

Average rainfall days - Union City, CA

The month with the highest number of rainy days is March (7.3 days).
The month with the least rainy days is July (0.3 days).

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Average daylight / Average sunshine
Union City, CA

Average daylight / Average sunshine - Union City, CA

The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).

The month with the most sunshine is July (Average sunshine: 12h and 12min).
The month with the least sunshine is December (Average sunshine: 6h and 0min).

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Average sunshine days
Union City, CA

Average sunshine days - Union City, CA

The months with the most sunshine days are July and August (30.4 days).
The month with the least sunshine days is February (22.2 days).

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Average UV index
Union City, CA

Average UV index - Union City, CA

The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 3).

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Average visibility
Union City, CA

Average visibility - Union City, CA

The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).

[Resources]

Union City, California, USA

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