June Weather in Fullerton, United States

Last updated: June 24, 2025

In June, the average temperature in Fullerton, United States is a pleasant 20°C (68°F). Expect a comfortable range with a minimum of 14°C (57°F) and a maximum of 33°C (91°F). This month brings light rainfall, with total precipitation averaging just 4 mm (0.2 in) over 0 days. The air feels fairly humid at 72%, creating a warm and inviting atmosphere.

June Temperature in Fullerton

In June in Fullerton, the average temperature is 20°C (68°F), with maximums reaching 33°C (91°F) and minimums dipping as low as 14°C (57°F). This mild climate makes Fullerton an ideal destination for travelers looking to enjoy pleasant outdoor activities during this time.

June Weather in Fullerton: Daily Temperature Highs, Lows, and Averages

The chart illustrates June temperature patterns in Fullerton, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Fullerton, June typically has an average temperature of 20°C (68°F), with highs reaching up to 33°C (91°F) and lows dropping to around 14°C (57°F).

Data source: Temperature data for Fullerton generated using information from the Copernicus Climate Change Service.

June Precipitation in Fullerton

In Fullerton in June, the precipitation amount is 4 mm (0.2 in) over the course of 0 days.

June Precipitation Trends in Fullerton

The chart displays monthly precipitation patterns in Fullerton, with values for each month alongside June’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how June’s conditions compare to those of other months. In Fullerton, June typically receives around 4 mm (0.2 inches) of precipitation spread over approximately 0 days.

Data source: Precipitation data for June generated using information from the Copernicus Climate Change Service.

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Millimeters (mm) Inches (in)

June Humidity in Fullerton

In Fullerton in June humidity is 72%. With an average temperature of 20°C (68°F), this humidity feels like a heavy blanket enveloping you, making every step slightly more laborious and the air thick with moisture, which can be uncomfortable for traveling.

June Average Humidity in Fullerton

This chart illustrates the average monthly humidity levels in Fullerton, with June’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In June, average humidity in Fullerton is approximately 72%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for June generated using information from the Copernicus Climate Change Service.

June UV Index in Fullerton

In Fullerton in June, the maximum UV index reaches 11, which corresponds to an extreme Exposure Category. With a time to burn of just 10 minutes, it's essential to take precautions. For more details, you can check the Hourly UV Index in Fullerton.

Maximum UV Index Levels in Fullerton for June

The chart shows the monthly maximum UV Index (UVI) for Fullerton in June, 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 June, the maximum UV index in Fullerton typically reaches 11, which falls under the extreme exposure category.

Data source: Fullerton June 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 June Weather in Fullerton Compares to Other Months

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

This table compares monthly weather conditions in Fullerton, showing how June’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	14°C (57°F)	65 mm (2.5 inches)	74%	moderate
February Weather	14°C (58°F)	52 mm (2.0 inches)	79%	high
March Weather	15°C (60°F)	55 mm (2.2 inches)	75%	very high
April Weather	17°C (63°F)	23 mm (0.9 inches)	70%	very high
May Weather	18°C (64°F)	12 mm (0.5 inches)	70%	very high
June Weather	20°C (68°F)	4 mm (0.2 inches)	72%	extreme
July Weather	22°C (72°F)	3 mm (0.1 inches)	73%	extreme
August Weather	23°C (73°F)	2 mm (0.1 inches)	69%	very high
September Weather	22°C (72°F)	3 mm (0.1 inches)	68%	very high
October Weather	20°C (69°F)	9 mm (0.4 inches)	67%	high
November Weather	17°C (63°F)	18 mm (0.7 inches)	68%	moderate
December Weather	14°C (58°F)	68 mm (2.7 inches)	71%	moderate