Union City (NJ) Temperature by Month

Union City, New Jersey, United States of America has an average annual maximum temperature of 17°C (63°F), ranging from 4°C (39°F) in January to 30°C (86°F) in July. Below you'll find a full monthly breakdown and a comparison with cities worldwide.

In Union City, temperatures can shift dramatically between very warm in summer and cold in winter. Nights follow the same pattern, with lows ranging from 22°C (72°F) in July to -3°C (27°F) in January.

The chart below illustrates the average maximum day and minimum night temperatures in Union City by month:

The coldest point of the day usually falls between 4 AM and 6 AM, with temperatures peaking around 3 PM. July, the city's warmest month, gets 271 hours of sunshine.

The chart below shows the average temperature throughout the year:

Union City's average annual maximum temperature is 17°C (63°F). To put that in context, here's how it compares to a few well-known destinations:

Athens, Greece sits at 23°C (73°F) on average, with hot dry summers and mild winters characteristic of the Mediterranean.

On the cooler end, Oslo, Norway averages just 10°C (50°F) annually, with pleasant summers but long, cold winters.

Osaka, Japan averages 22°C (72°F) annually, with hot humid summers, mild winters, and pleasant spring and autumn seasons.

Melbourne, Australia averages 20°C (68°F) annually, known for unpredictable weather, with four seasons sometimes happening in one day.

Temperature alone doesn't tell the whole story, humidity plays a big role in how warm or cold it actually feels. High humidity in summer makes the heat feel more intense, particularly once temperatures climb above 25°C. In winter, the same humidity can make cold air feel sharper than the thermometer suggests.

In the cooler months, when temperatures drop below 10°C, high humidity makes the cold feel more cutting than it would in dry conditions.

In Union City, January is the coolest month, with average highs of 4°C (39°F) and humidity around 61%, considered high. In July, the warmest month, temperatures average 30°C (86°F) with 64% humidity, conditions that feel high. For a full picture, see our humidity page.

Climate temperature data is typically calculated as a 30-year average. This smooths out year-to-year variability and gives a more reliable picture of what a place is actually like, rather than what happened in any single unusual year.

The readings come from a range of sources, land-based weather stations, ocean buoys, ships, and satellites. That data is collected by weather services around the world, then pooled, quality-checked, and averaged to produce the climate records you see here.

For cities and regions with significant elevation, altitude is one of the biggest factors shaping local temperatures. As a rule of thumb, temperatures fall by around 6°C for every 1,000 metres gained, so a city at 2,000 metres will typically be around 12°C cooler than a city at sea level in the same region. Higher ground also tends to see more dramatic day-to-night temperature swings, since thinner air loses heat faster after sunset.

For more on Union City's weather, including monthly rainfall, sunshine hours, and humidity, visit our Union City climate page.