Union City has a **humid subtropical climate** under the Köppen classification **Cfa**, similar to much of the Atlanta region. The city experiences hot, humid summers; generally mild winters; and precipitation spread through the year.
| Climate Factor | Typical Pattern | |---|---| | Summer temperatures | Often highs in the upper 80s to low 90s °F (31–34 °C) | | Winter temperatures | Often highs in the 40s to 50s °F (7–15 °C), with colder nights | | Rainfall | Fairly well distributed year-round; the Atlanta region averages around 50 inches annually | | Snowfall | Usually light and infrequent; some winters have little or none | | Humidity | Moderate to high, especially in summer |
Spring and autumn are often considered the most comfortable times to visit, with milder temperatures and less oppressive humidity than midsummer. Summer brings thunderstorms, and severe weather is possible at times, including strong winds, hail, and occasional tornado risk typical of Georgia. Heavy rain can lead to localized flooding in low-lying or poorly drained areas.
Winter weather is usually manageable, but rare ice events can disrupt travel more than snowfall itself. Union City is far enough inland that it does not face direct coastal hurricane landfall, though remnants of tropical systems can bring heavy rain and wind to north and central Georgia.