ST. HELENA, SAINT HELENA

Average Temperature

Years on Record: 17

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		65		68		70		70		69		67		64		62		61		62		62		63		65

Average High Temperature

Years on Record: 17

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		67		71		72		72		71		69		66		64		63		64		64		65		68

Average Low Temperature

Years on Record: 17

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		63		65		67		67		66		64		62		60		59		59		59		61		63

Highest Recorded Temperature

Years on Record: 17

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		90		90		84		87		90		85		83		80		80		80		77		81		83

Lowest Recorded Temperature

Years on Record: 17

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		52		59		60		60		61		57		54		53		52		53		52		56		57

Average Number of Days Below 75F/23C

Years on Record: 17

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		365		31		28		31		30		31		30		31		31		30		31		30		31

Average Number of Days Below 65F/18C

Years on Record: 17

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		272		20		5		4		9		22		30		31		31		30		31		30		30

Average Number of Days With Precipitation

Years on Record: 14

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		212		15		18		18		15		16		16		18		20		18		21		19		18

Average Number of Rainy Days

Years on Record: 14

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		212		15		18		18		15		16		16		18		20		18		21		19		18

Average Morning Relative Humidity

Years on Record: 14

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
%		87		89		90		89		88		85		84		84		85		85		86		87		87

Average Evening Relative Humidity

Years on Record: 7

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
%		77		76		76		77		78		77		77		78		79		78		78		77		75

Average Dew Point

Years on Record: 11

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		59		62		64		64		63		60		58		56		55		56		56		57		59

Heating Degree Days

Years on Record: 17

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		520.5		---		---		---		---		---		30		93		124		105		108.5		60		---

Cooling Degree Days

Years on Record: 17

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		526.6		93		127.1		139.5		105		46.5		---		---		---		---		---		---		15.5

Growing Degree Days

Years on Record: 17

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		5484.9		558		550.9		604.5		555		511.5		420		372		341		345		356.5		390		480.5

Average Length of Day

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Hours		12.5		13.3		13		12.5		12.1		11.7		11.6		11.7		12		12.4		12.8		13.2		13.5

Average Number of Days With Fog

Years on Record: 14

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		48		4		5		4		3		2		4		4		5		5		4		4		4

Average Number of Days With Smoke/Haze

Years on Record: 14

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		9		---		---		---		1		1		1		2		1		1		1		1		---

Average No. of Days With Vision Obstruction

Years on Record: 14

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		60		4		5		5		4		3		5		6		6		7		5		5		5

Average Wind Speed

Years on Record: 11

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mph		16		14		14		16		14		14		16		17		17		17		17		16		16

Average No. of Days With Blowing Dust/Sand

Years on Record: 14

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		60		4		5		5		4		3		5		6		6		7		5		5		5

Average Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		5.7		7.2		7.3		6.7		5.8		5		4.5		4.5		4.7		5.1		5.5		5.9		6.5

Average Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		1.8		2.1		1.9		1.7		1.5		1.3		1.2		1.3		1.6		2		2.3		2.4		2.3

Average Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		5.9		7		6.9		6.7		6.3		5.7		5.3		5.1		5.1		5.2		5.3		5.8		6.6

Average Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		6		7.3		7.6		7.2		6.8		6.4		5.9		5.5		5		4.7		4.6		5		6.1

Maximum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		5.7		7.2		7.3		6.7		5.8		5		4.5		4.5		4.7		5.1		5.5		5.9		6.5

Maximum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		2		2.3		2.3		2		1.7		1.4		1.4		1.5		1.7		2.1		2.3		2.5		2.5

Maximum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		6.5		7.7		7.3		7.3		6.8		6.1		5.9		6		5.6		5.8		5.9		6.5		7.5

Maximum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		7.2		8.6		8.6		8.4		7.9		7.2		7.1		7.1		5.9		5.7		5.7		6.4		7.6

Minimum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		5.1		6.4		6.1		5.9		5.1		4.7		3.8		3.9		4.2		4.4		5.1		5.2		5.8

Minimum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		1.6		1.8		1.7		1.5		1.3		1.1		1		1.1		1.5		1.8		2.1		2.2		2

Minimum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		5.2		6.3		5.8		5.9		5.4		5.3		4.4		4.3		4.5		4.5		4.9		5.1		5.9

Minimum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		4.7		5.8		5.4		5.7		5.2		5.7		4.3		4.2		3.9		3.5		3.9		3.9		4.9