September Weather in San Rafael

Last updated: March 2, 2024

The weather in San Rafael, United States, during September is characterized by an average temperature of 18°C (65°F). Highs can soar to 31°C (87°F), while lows may dip to 4°C (40°F). Typically, the humidity level in San Rafael throughout September hovers around 62%.

4°C (40°F)

Minimum temperature

18°C (65°F)

Average temperature

31°C (87°F)

Maximum temperature

62%

Humidity

Precipitation and Sunshine hours

In September, San Rafael averages 32 mm (1.3 inches) of rainfall, typically over the course of 5 rainy days. The month enjoys an average of 12 hours 20 minutes of daylight, with the sun shining for approximately 10 hours 23 minutes each day. Additionally, there is a 67% probability of sunny days during this period.

32 mm (1.3 inches)

Precipitation

5 rainy days

Rainy days

10 hours 23 minutes

Sunshine hours

67%

Chance of sun

UV Index

In September, the UV Index in San Rafael reaches a maximum of 11, indicating a level of Extreme exposure. The most intense UV radiation typically occurs between 13:00 and 15:00, during which unprotected skin may burn in as little as 10 minutes.

Average solar exposure data for the current time of the year. Actual values may vary and depend on many factors, such as cloud cover, vegetation cover, surface type, etc.
  07:00 08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00
UVI 1 1 3 5 8 10 11 10 8 5 3 1 1
Exposure Low Moderate VeryHigh Extreme VeryHigh Moderate Low
Time to burn 45 min 30 min 15 min 10 min 15 min 30 min 45 min

Compare San Rafael's Climate with Cities Worldwide