Last updated: June 24, 2025
In December, the average temperature in Mountain View, United States hovers around 5°C (41°F). Weather conditions can vary significantly, with minimum temperatures plunging to -13°C (9°F) and peaking at a balmy 25°C (77°F). Prepare for potential rain, as 71 mm (2.8 in) of precipitation can be expected over approximately 7 days. Don't forget, the average humidity sits high at 86%, making it feel even cooler or warmer depending on the temperature fluctuations.
In December in Mountain View, the average temperature is 5°C (41°F). The maximum can reach 25°C (77°F), while the minimum can drop to as low as -13°C (9°F). This range of temperatures makes Mountain View an interesting destination for travelers seeking a mix of cool and mild weather.
In Mountain View in December, the precipitation amount is 71 mm (2.8 in) over a span of 7 days.
In Mountain View in December humidity is 86%. With an average temperature of 5°C (41°F), this humidity feels like a heavy, damp blanket wrapping around you, making outdoor activities uncomfortable and travel quite challenging due to the chill combined with the stickiness in the air.
In Mountain View in December, the maximum UV index is 3, which corresponds to a moderate Exposure Category. The time to burn is approximately 30 minutes. For more details on the hourly UV index in Mountain View, you can check the information here.
UV Risk Categories
Weather in Mountain View varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Mountain View, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | 2°C (35°F) | 79 mm (3.1 inches) | 83% | moderate |
| February Weather | 3°C (39°F) | 107 mm (4.2 inches) | 81% | high |
| March Weather | 9°C (49°F) | 148 mm (5.8 inches) | 80% | high |
| April Weather | 13°C (55°F) | 164 mm (6.5 inches) | 80% | very high |
| May Weather | 19°C (66°F) | 189 mm (7.4 inches) | 83% | extreme |
| June Weather | 24°C (75°F) | 77 mm (3.0 inches) | 83% | extreme |
| July Weather | 26°C (79°F) | 80 mm (3.2 inches) | 76% | extreme |
| August Weather | 24°C (76°F) | 108 mm (4.2 inches) | 69% | very high |
| September Weather | 22°C (72°F) | 53 mm (2.1 inches) | 68% | very high |
| October Weather | 15°C (59°F) | 122 mm (4.8 inches) | 72% | high |
| November Weather | 8°C (46°F) | 73 mm (2.9 inches) | 83% | moderate |
| December Weather | 5°C (41°F) | 71 mm (2.8 inches) | 86% | moderate |