Union City, California Climate by Month
Union City, California, United States
Warm summers and mild winters, with most rain from December to March.
Warm summers and mild winters, with most rain from December to March: that's Union City's climate in short. Expect highs of 82°F (28°C) in August and 60°F (15°C) in January, with the coldest nights (December) near 42°F (5°C). Of the 16 in (394 mm) of rain in a typical year, 71% falls from December to March. June to September are almost completely dry.
- Warmest month
- 82°F(28°C)
- Average high, August
- Coldest nights
- 42°F(5°C)
- Average low, December
- Rain per year
- 16 in(394 mm)
- Wettest: January
- Humidity
- 64%
- Sunniest: June
Best and worst months in Union City
Best for weatherMay, June and October are the best time for weather in Union City: highs near 77°F (25°C) and almost no rain.
Least pleasantDecember and January are the least pleasant; January is the coldest, with highs of only 60°F (15°C).
Comfort combines how close the afternoon high is to 75°F (24°C) with how much rain falls and how humid it is. See where the weather is best in May.
Temperature and rain through the year
Highs and lows (°F)
Average highAverage low
Rain (in per month)
Union City weather by month
| Month | High | Low | Rain | Humidity | Sun |
|---|---|---|---|---|---|
| JanJanuary | 60°F(15°C) | 42°F(6°C) | 3.1 in(78 mm) | 71% | 1.9 |
| FebFebruary | 63°F(17°C) | 44°F(7°C) | 2.8 in(72 mm) | 72% | 2.7 |
| MarMarch | 66°F(19°C) | 46°F(8°C) | 2.3 in(58 mm) | 65% | 4.3 |
| AprApril | 70°F(21°C) | 48°F(9°C) | 1.2 in(30 mm) | 65% | 5.5 |
| MayMayBest | 74°F(23°C) | 51°F(11°C) | 0.4 in(11 mm) | 62% | 6.4 |
| JunJuneBest | 79°F(26°C) | 55°F(13°C) | 0.1 in(3 mm) | 58% | 7.4 |
| JulJuly | 81°F(27°C) | 57°F(14°C) | 0.0 in(1 mm) | 58% | 7.3 |
| AugAugust | 82°F(28°C) | 57°F(14°C) | 0.0 in(1 mm) | 61% | 6.5 |
| SepSeptember | 82°F(28°C) | 56°F(13°C) | 0.1 in(2 mm) | 58% | 5.4 |
| OctOctoberBest | 77°F(25°C) | 52°F(11°C) | 0.9 in(24 mm) | 58% | 3.9 |
| NovNovember | 67°F(20°C) | 46°F(8°C) | 1.7 in(43 mm) | 64% | 2.6 |
| DecDecember | 60°F(16°C) | 42°F(5°C) | 2.8 in(71 mm) | 71% | 1.8 |
1991–2020 averages. Sun is solar radiation in kWh/m² per day. Highlighted: the most comfortable months.
Places with a similar climate outside the United States
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