September Weather in Fullerton

Last updated: March 2, 2024

The weather in Fullerton, United States, during September is characterized by an average temperature of 22°C (72°F). Highs can soar to 33°C (93°F), while lows may dip to 16°C (61°F). Typically, the humidity level in Fullerton throughout September hovers around 68%.

16°C (61°F)

Minimum temperature

22°C (72°F)

Average temperature

33°C (93°F)

Maximum temperature

68%

Humidity

Precipitation and Sunshine hours

In September, Fullerton averages 3 mm (0.1 inches) of rainfall, typically over the course of 0 rainy days. The month enjoys an average of 12 hours 19 minutes of daylight, with the sun shining for approximately 10 hours 32 minutes each day. Additionally, there is a 68% probability of sunny days during this period.

3 mm (0.1 inches)

Precipitation

0 rainy days

Rainy days

10 hours 32 minutes

Sunshine hours

68%

Chance of sun

UV Index

In September, the UV Index in Fullerton reaches a maximum of 10, indicating a level of VeryHigh exposure. The most intense UV radiation typically occurs between 12:00 and 14:00, during which unprotected skin may burn in as little as 15 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 10 9 6 4 2 1 1
Exposure Low Moderate VeryHigh High Moderate Low
Time to burn 45 min 30 min 15 min 25 min 30 min 45 min

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