ATTU ISLAND, ALASKA

Average Temperature

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		3.8		-0.9		-1		---		1.6		3.8		6.6		9.1		10.3		8.8		5.6		1.9		-0.1

Average High Temperature

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		6.1		1.3		1.1		---		3.6		5.9		9.1		11.4		12.8		11.2		8.2		4.4		2.1

Average Low Temperature

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		1.4		-3.2		-3.1		---		-0.6		1.7		4.1		6.8		7.7		6.3		3		-0.6		-2.2

Highest Recorded Temperature

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		32.2		9.4		10.6		32.2		15		17.8		22.2		21.1		20		16.1		12.2		9.4		32.2

Lowest Recorded Temperature

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		-26.1		-15		-13.9		-12.2		-9.4		-7.2		-4.4		-2.2		-6.7		-6.1		-26.1		-16.7		-26.1

Average Number of Days Below 32F/0C

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		157		31		26		25.1		19.6		5.7		1.2		0.1		0.6		1.2		4.6		18.1		24.2

Average Number of Days Below 0F/-17C

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		0.2		---		---		---		---		---		---		---		---		---		0.1		---		0.1

Average Precipitation

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		1330		90		90		80		90		70		70		100		150		160		160		110		110

Average Number of Days With Precipitation

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		197		19		17		18		16		13		11		13		15		17		19		20		19

Most Reported Precipitation in a Month

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		538		237		188		174		204		151		191		261		538		394		293		237		258

Least Reported Precipitation in a Month

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		1		13		10		22		25		1		2		33		25		2		15		7		18

Most Precipitation Reported in a Day

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		254		63.5		92		68.6		88.9		59.4		114.8		228.6		254		116.6		109.2		101.6		86.4

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

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		114		11		10		9		9		7		5		8		10		11		12		11		11

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

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		30		2		2		1		2		2		2		2		4		4		4		3		2

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

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		13		1		1		---		1		---		1		1		2		2		2		1		1

Average Snowfall

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
cm		194.1		41.1		42.9		38.1		16.5		2.8		---		---		---		---		1.5		18		33

Average Snow Cover

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
cm		7		17		25		25		12		---		---		---		---		---		---		2		5

Most Snow Reported in a Month

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
cm		109		90.2		88.1		109		89.2		41.4		---		---		---		---		23.4		63.8		85.3

Heating Degree Days

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		3285		424.4		390.6		405		337.8		277.2		185.6		116.1		81.1		121.7		221.7		325.6		398.3

Growing Degree Days

Years on Record: 45

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		8.6		---		---		---		---		---		---		8.6		---		---		---		---		---

Average Length of Day

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Hours		12.9		8.9		10.5		12.5		14.6		16.6		17.6		17.1		15.3		13.2		11.2		9.4		8.4

Average Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		9.1		2.7		5.2		9.1		13.1		15.9		15.1		14.2		12.1		9.8		6.4		3.1		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		5.5		1.8		3.1		5.3		7.5		9.1		9.6		9.1		7.7		5.6		3.7		2.1		1.4

Average Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		9.9		4.9		8		11.3		13.6		14.4		13.1		12.5		11.6		11.3		9.3		5.3		4

Average Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		8.1		4.4		7		9.5		11.4		12.1		9.7		9		8.2		9.6		8.3		4.6		3.5

Maximum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		9.1		2.7		5.2		9.1		13.1		15.9		15.1		14.2		12.1		9.8		6.4		3.1		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		2		3.4		5.5		7.5		9.2		10.1		9.6		8.1		5.9		4.1		2.3		1.6

Maximum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		11.9		6.3		9.5		12.8		16.1		16.9		15.8		14.7		14.4		13.9		11.2		6.2		4.9

Maximum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		10.9		5.8		8.6		11.3		15.3		16.7		14.5		12.6		12.4		12.9		10.4		5.7		4.4

Minimum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		7.5		2.2		4.3		8.3		10.3		13.4		12.5		12.1		9.4		7.8		5.6		2.7		1.7

Minimum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		5.1		1.6		2.7		5.1		7		8.8		8.8		8.5		6.7		5.1		3.4		1.9		1.3

Minimum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		8		3.6		6.3		10		10.2		12.2		10.8		10.7		8.8		8.5		7.8		4.4		3.2

Minimum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		5.7		3		5.2		7.9		6.7		8.3		6.5		6.4		5		6.1		6.8		3.7		2.6