Fullerton, CA: Climate and Weather (2024)

Seasonal Weather Patterns in Fullerton, CA

Temperature

Average Daily Temperature (°F)

	Fullerton, CA	U.S. Avg.	Difference
January	53	43	+10
July	72	79	-7

Average Monthly Number of Hot and Freezing Days

	Fullerton, CA	U.S. Avg.	Difference
Summer: Hot Days	5	11	-6
Winter: Freezing Days	0	12	-12

Read more in Temperature

Sunshine

Average Annual Number of Clear and Cloudy Days

	Fullerton, CA	U.S. Avg.	Difference
Clear Days	294	217	+77
Cloudy Days	71	148	-77

Average Daylight Hours per Day

	Fullerton, CA	U.S. Avg.	Difference
January	10	10	No difference
July	14	15	-1

Read more in Sunshine

Precipitation

Average Annual Number of Rainy and Snow Days

	Fullerton, CA	U.S. Avg.	Difference
Rainy Days	31	38	-7
Snow Days	0	7	-7

Average Monthly Humidity (%) in Fullerton, CA

	Fullerton, CA	U.S. Avg.	Difference
January	58	68	-10%
July	54	61	-7%

Read more in Precipitation

Is Fullerton, CA, Hot or Cold?

Low, Average, and High Temperatures (°F)

	Low	Average	High
January	46	53	62
February	46	54	63
March	49	57	65
April	51	59	72
May	55	64	74
June	58	69	79
July	64	72	82
August	63	73	83
September	62	70	82
October	55	66	77
November	50	58	67
December	47	55	63

Average Monthly Number of Hot Days

	Fullerton, CA	U.S. Avg.	Difference
January	0	0	No difference
February	0	0	No difference
March	1	0	+1
April	1	1	No difference
May	2	3	-1
June	2	8	-6
July	6	13	-7
August	8	12	-4
September	6	6	No difference
October	4	2	+2
November	1	0	+1
December	0	0	No difference

Average Monthly Number of Freezing Days

	Fullerton, CA	U.S. Avg.	Difference
January	0	13	-13
February	0	10	-10
March	0	7	-7
April	0	2	-2
May	0	0	No difference
June	0	0	No difference
July	0	0	No difference
August	0	0	No difference
September	0	0	No difference
October	0	2	-2
November	0	6	-6
December	0	12	-12

Fullerton, CA: Clear/Cloudy Skies, and Daylight Hours

Average Number of Clear Days

	Fullerton, CA	U.S. Avg.	Difference
January	23	17	+6
February	21	16	+5
March	23	17	+6
April	24	17	+7
May	25	18	+7
June	26	19	+7
July	27	20	+7
August	28	20	+8
September	26	19	+7
October	25	19	+6
November	24	18	+6
December	22	17	+5

Average Number of Cloudy Days

	Fullerton, CA	U.S. Avg.	Difference
January	8	14	-6
February	7	12	-5
March	8	14	-6
April	6	13	-7
May	6	13	-7
June	4	11	-7
July	4	11	-7
August	3	11	-8
September	4	11	-7
October	6	12	-6
November	6	12	-6
December	9	14	-5

Average Daylight Hours per Day

	Fullerton, CA	U.S. Avg.	Difference
January	10	10	No difference
February	11	11	No difference
March	12	12	No difference
April	13	13	No difference
May	14	14	No difference
June	14	15	-1
July	14	15	-1
August	14	14	No difference
September	13	13	No difference
October	12	12	No difference
November	11	10	+1
December	10	10	No difference

Fullerton, CA: Rainy Days, Snow Days, and Humidity

Average Number of Rainy Days

	Fullerton, CA	U.S. Avg.	Difference
January	6	9	-3
February	6	8	-2
March	5	9	-4
April	2	7	-5
May	1	7	-6
June	1	7	-6
July	0	7	-7
August	0	6	-6
September	1	7	-6
October	2	7	-5
November	2	8	-6
December	5	8	-3

Average Number of Snow Days

	Fullerton, CA	U.S. Avg.	Difference
January	0	2	-2
February	0	2	-2
March	0	1	-1
April	0	0	No difference
May	0	0	No difference
June	0	0	No difference
July	0	0	No difference
August	0	0	No difference
September	0	0	No difference
October	0	0	No difference
November	0	1	-1
December	0	2	-2

Average Humidity (%)

	Fullerton, CA	U.S. Avg.	Difference
January	58	68	-10%
February	60	66	-6%
March	59	63	-4%
April	57	59	-2%
May	58	61	-3%
June	57	60	-3%
July	54	61	-7%
August	54	62	-8%
September	54	63	-9%
October	55	63	-8%
November	55	65	-10%
December	58	68	-10%

The assessments presented on this website, including those related to crime, safety, cost of living, and other location characteristics (e.g., states, cities, towns, villages, neighborhoods, areas, landmarks), are based on various sources and our internal research methods. These assessments are not guaranteed to be accurate or complete and should not be used as the sole basis for making any decisions.