December Weather in San Leandro, United States

Last updated: June 24, 2025

In December, the average temperature in San Leandro, United States hovers around 10°C (51°F), with a comfortable range between a minimum of 2°C (35°F) and a maximum of 23°C (74°F). Expect 80 mm (3.2 in) of precipitation spread over 8 days, contributing to an average humidity level of 80%. Stay prepared for a blend of cool days and refreshing rain!

December Temperature in San Leandro

In December in San Leandro, the average temperature is 10°C (51°F). Maximum temperatures can reach up to 23°C (74°F), while the minimum can drop to as low as 2°C (35°F). Be sure to pack layers to stay comfortable during your travels!

December Weather in San Leandro: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in San Leandro, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In San Leandro, December typically has an average temperature of 10°C (51°F), with highs reaching up to 23°C (74°F) and lows dropping to around 2°C (35°F).
JanFebMarAprMayJunJulAugSepOctNovDec515254576064646566625550
Data source: Temperature data for San Leandro generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

December Precipitation in San Leandro

In San Leandro in December, the total precipitation amount is 80 mm (3.2 in), occurring over a span of 8 days.

December Precipitation Trends in San Leandro

The chart displays monthly precipitation patterns in San Leandro, with values for each month alongside December’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how December’s conditions compare to those of other months. In San Leandro, December typically receives around 80 mm (3.2 inches) of precipitation spread over approximately 8 days.
JanFebMarAprMayJunJulAugSepOctNovDec94917430182001244281
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

December Humidity in San Leandro

In San Leandro in December, humidity is 80%. With an average temperature of 10°C (51°F), this humidity feels like a damp layer clinging to the skin, making outdoor activities uncomfortable and requiring travelers to dress in layers to cope with the chill and moisture in the air.

December Average Humidity in San Leandro

This chart illustrates the average monthly humidity levels in San Leandro, with December’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In December, average humidity in San Leandro is approximately 80%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec82%84%82%78%71%64%59%54%55%62%78%80%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in San Leandro

In San Leandro 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 San Leandro, you can check the information here.

Maximum UV Index Levels in San Leandro for December

The chart shows the monthly maximum UV Index (UVI) for San Leandro in December, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In December, the maximum UV index in San Leandro typically reaches 3, which falls under the moderate exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec3589101111109743
Data source: San Leandro December UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

How December Weather in San Leandro Compares to Other Months

Weather in San Leandro varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in San Leandro, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in San Leandro, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather10°C (51°F)94 mm (3.7 inches)82%moderate
February Weather11°C (53°F)91 mm (3.6 inches)84%moderate
March Weather12°C (54°F)73 mm (2.9 inches)82%very high
April Weather14°C (58°F)29 mm (1.2 inches)78%very high
May Weather15°C (60°F)18 mm (0.7 inches)71%very high
June Weather18°C (64°F)2 mm (0.1 inches)64%extreme
July Weather18°C (64°F)0 mm (0.0 inches)58%extreme
August Weather18°C (65°F)0 mm (0.0 inches)54%very high
September Weather19°C (66°F)1 mm (0.0 inches)55%very high
October Weather17°C (63°F)24 mm (1.0 inches)62%high
November Weather13°C (56°F)42 mm (1.7 inches)78%moderate
December Weather10°C (51°F)80 mm (3.2 inches)80%moderate

Compare San Leandro's Climate with Cities Worldwide