ALTADENA, CALIFORNIA

Average Temperature

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		16.7		11.8		12.3		13.2		13.5		17		18.9		22.1		22.8		21.9		17.9		15.9		12.9

Average High Temperature

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		23.4		17.9		18		19.2		19.4		23.9		26.2		29.9		30.4		29.2		24.9		22.7		18.8

Average Low Temperature

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		10		5.7		6.6		7.1		7.7		10.1		11.6		14.3		15.1		14.7		11		9.2		7

Highest Recorded Temperature

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		41.1		30		29.4		31.7		33.3		38.3		38.3		41.1		40.6		41.1		37.8		33.3		30

Lowest Recorded Temperature

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		-3.3		-2.8		-3.3		-0.6		---		2.8		5		8.9		10		7.2		2.8		2.2		-1.1

Average Number of Days Above 90F/32C

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		38.2		---		---		---		0.6		2		3.8		8		10.2		9.8		3		0.7		---

Average Number of Days Below 32F/0C

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		3.3		0.8		1		0.4		0.2		---		---		---		---		---		---		---		0.9

Average Precipitation

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		559		117		122		90		46		11		4		1		2		11		21		51		83

Average Number of Days With Precipitation

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		40		6		6		6		5		3		2		---		1		1		2		3		5

Most Reported Precipitation in a Month

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		620		620		463		358		327		152		44		26		58		161		232		448		311

Most Precipitation Reported in a Day

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		229.1		229.1		152.4		211.6		128.8		57.9		33		8.9		57.7		112.8		103.6		172.2		138.4

Avg. No. of Days w/Precip. Above 0.1in/2.5mm

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		25.7		4.8		4.9		4.2		2.1		0.9		0.4		0.1		0.2		0.7		1.8		2.2		3.4

Avg. No. of Days w/Precip. Above 0.2in/5mm

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		27		5		5		4		3		1		1		---		---		1		1		2		4

Avg. # of Days w/Precip. Above 0.4in/10mm

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		12		2		3		2		1		---		---		---		---		---		1		1		2

Avg. No. of Days w/Precip. Above 0.5in/13mm

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		14.3		2.8		3.3		2.2		1.1		0.3		0.1		---		---		0.4		0.8		1.3		2

Avg. No. of Days w/Precip. Above 1in/25mm

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		8		2		2		1		1		---		---		---		---		---		---		1		1

Heating Degree Days

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		235.6		61.7		49.4		36.7		30		1.7		---		---		---		---		2.2		8.9		45

Cooling Degree Days

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		520.6		1.7		4.4		4.4		7.2		22.2		53.3		116.1		138.3		117.2		41.1		12.8		1.7

Growing Degree Days

Years on Record: 89

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		2523.5		56.8		65.9		98.2		105		217		266.7		373.7		396.1		358.3		246.3		178.3		89.6

Average Length of Day

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Hours		12.6		10.6		11.4		12.4		13.5		14.4		14.9		14.6		13.8		12.8		11.7		10.8		10.4

Average Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		19.3		10.9		13.9		19.2		23.9		26.6		27.7		26.1		23.9		20.4		15.9		12.3		10.2

Average Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		4.9		3		3.9		4.7		5.7		6.5		6.8		7		6.2		5.1		4		3		2.7

Average Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		21.2		16.7		18.8		22.6		24.2		24.1		23.9		23.1		23.1		22.5		20.8		18.3		16.3

Average Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		24.9		19.2		20.4		25.4		28.7		30.1		30.9		28.5		27.2		25.5		23		21.4		18.9

Maximum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		19.3		10.9		13.9		19.2		23.9		26.6		27.7		26.1		23.9		20.4		15.9		12.3		10.2

Maximum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		5.8		3.6		4.6		5.9		6.7		7.8		8.2		8.2		7		5.9		4.7		3.5		3.1

Maximum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		24.2		18.9		23.5		25.7		26.4		26.1		26.4		26.2		26.5		25.4		25.7		21.1		18.9

Maximum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		30.9		22.7		27.8		30.9		33.3		35		37.9		36.4		34.7		31		31.4		25.9		23

Minimum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		16.9		8.9		11.4		15.9		21.2		23.3		24.3		22.8		21.9		18.3		14.2		10.9		8.8

Minimum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		3.8		2.6		2.9		3.7		4.7		5.4		5.3		5.3		4.7		4.1		2.7		2.4		2.2

Minimum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		18.1		12.6		14.7		18		21.4		21.2		21.2		20.4		21.1		19.8		18		15.5		13.5

Minimum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		19.1		12.9		14		17.5		22.8		23.3		23.9		21.8		22.8		20.6		18.4		16.9		14.5