June Weather in Fullerton, United States

Last updated: June 24, 2025

In June, the average temperature in Fullerton, United States hovers around 24°C (75°F), with a range that can dip to a cool 9°C (49°F) and rise to a scorching 38°C (101°F). Expect 97 mm (3.8 in) of precipitation spread over 8 days throughout the month, and prepare for a fairly high average humidity of 83%.

June Temperature in Fullerton

In June, in Fullerton, the average temperature is 24°C (75°F), with maximums reaching up to 38°C (101°F) and minimums dropping as low as 9°C (49°F). This variation in temperature makes it advisable for travelers to pack a range of clothing to accommodate both warm days and cooler evenings.

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 24°C (75°F), with highs reaching up to 38°C (101°F) and lows dropping to around 9°C (49°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 total precipitation amount is 97 mm (3.8 in), occurring over a span of 8 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 97 mm (3.8 inches) of precipitation spread over approximately 8 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 83%. With an average temperature of 24°C (75°F), this humidity feels like a warm blanket enveloping you, which can be quite stifling for traveling. You may find yourself frequently seeking shade or air conditioning, and it's wise to stay hydrated while exploring.

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 83%, 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	-4°C (26°F)	28 mm (1.1 inches)	73%	moderate
February Weather	-4°C (25°F)	20 mm (0.8 inches)	81%	moderate
March Weather	4°C (40°F)	89 mm (3.5 inches)	69%	high
April Weather	9°C (49°F)	57 mm (2.2 inches)	71%	very high
May Weather	16°C (61°F)	142 mm (5.6 inches)	80%	very high
June Weather	24°C (75°F)	97 mm (3.8 inches)	83%	extreme
July Weather	25°C (78°F)	65 mm (2.5 inches)	84%	very high
August Weather	23°C (74°F)	84 mm (3.3 inches)	84%	very high
September Weather	20°C (69°F)	57 mm (2.2 inches)	77%	very high
October Weather	11°C (52°F)	83 mm (3.3 inches)	72%	high
November Weather	4°C (40°F)	22 mm (0.9 inches)	80%	moderate
December Weather	-1°C (31°F)	42 mm (1.6 inches)	79%	moderate