POWDER RIVER, WYOMING

Average Temperature

Years on Record: 46

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		44.6		22.4		25.9		34.5		42.5		51.8		61.2		70.2		68.1		57.7		45.7		31.8		23.3

Average High Temperature

Years on Record: 46

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		59.2		34.2		38.1		47.5		56.5		66.9		77.9		88.4		86.4		74.4		60.6		44.3		35.5

Average Low Temperature

Years on Record: 46

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		29.9		9.8		13.5		21.6		28.6		36.7		44.5		51.9		49.8		40.8		30.9		19.3		10.9

Highest Recorded Temperature

Years on Record: 46

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		109		60		65		74		82		96		101		109		104		99		86		77		63

Lowest Recorded Temperature

Years on Record: 46

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		-45		-42		-33		-18		-8		12		24		30		26		10		-5		-30		-45

Average Number of Days Above 100F/38C

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		0.7		---		---		---		---		---		---		0.5		0.3		---		---		---		---

Average Number of Days Above 90F/32C

Years on Record: 46

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		32.4		---		---		---		---		0.2		3.6		15.3		11.5		1.9		---		---		---

Average Number of Days Above 80F/26C

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		80.7		---		---		---		0.6		3.1		13.5		26.6		26.1		10.3		0.5		---		---

Average Number of Days Above 70F/21C

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		127.7		---		---		0.4		3.1		12.5		23.6		30.1		29.9		21		6.4		0.7		---

Average Number of Days Above 60F/15C

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		174.9		---		0.2		3.8		12.3		21.4		28.6		31		30.9		26.9		16.1		3.8		---

Average Number of Days Above 50F/10C

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		223.6		1.5		3.1		13.9		20.8		28.1		29.6		31		31		29.1		23.9		10.1		1.5

Average Number of Days Above 40F/4C

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		280.1		10.1		13		22.8		27.7		30.7		30		31		31		29.9		28.2		18		7.7

Average Number of Days Below 70F/21C

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		364.9		31		28		31		30		31		30		31		31		30		31		30		31

Average Number of Days Below 60F/15C

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		358.5		31		28		31		30		31		29.7		27.7		28.7		29.5		31		30		31

Average Number of Days Below 50F/10C

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		317.9		31		28		31		29.9		30.3		24.4		11		14.3		26		31		30		31

Average Number of Days Below 40F/4C

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		249.2		31		28		30.6		27.7		20.8		5.8		0.9		1.8		13.9		28.3		29.4		31

Average Number of Days Below 32F/0C

Years on Record: 46

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		193.6		30		27.1		27		20.4		8.7		0.8		0.1		0.2		4.9		18.2		26.5		29.7

Average Number of Days Below 20F/-6C

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		106.3		25		19		11.7		4.1		0.3		---		---		---		0.4		3.6		16		26.3

Average Number of Days Below 10F/-12C

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		52.8		14.4		9.8		3.7		0.4		---		---		---		---		---		0.5		6.8		17

Average Number of Days Below 0F/-17C

Years on Record: 46

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		21		7.1		4.4		1		---		---		---		---		---		---		0.1		2.1		6.1

Average Precipitation

Years on Record: 46

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
in		10.9		0.4		0.4		0.8		1.1		2.1		1.5		1.2		0.7		0.8		0.9		0.6		0.4

Average Number of Days With Precipitation

Years on Record: 46

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		48		3		3		4		5		7		5		4		4		3		4		3		3

Most Reported Precipitation in a Month

Years on Record: 46

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
in		6.7		1.1		1.5		3.1		5.1		6.7		6		3.3		1.9		2.7		3		2.5		1.8

Least Reported Precipitation in a Month

Years on Record: 46

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

Most Precipitation Reported in a Day

Years on Record: 46

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
in		2.2		0.8		0.9		1.4		1.2		1.9		2.2		2.2		1.2		1.5		1.3		1.1		1

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		25.5		1.1		1.3		1.9		2.5		4.6		3.5		2.3		1.7		2		2.1		1.6		0.9

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

Years on Record: 46

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		28		1		1		2		3		5		4		3		2		2		2		2		1

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

Years on Record: 46

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

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		5.3		---		0.2		0.3		0.3		1		0.9		0.7		0.4		0.7		0.5		0.3		---

Average Snowfall

Years on Record: 46

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
in		47.1		5.9		6.3		9.2		6.6		1.9		---		---		---		0.8		5.2		6.1		5.1

Average Number of Days With Snow

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		14.2		1.9		2.3		2		2.1		0.5		---		---		---		0.3		1.4		2.1		1.6

Average Snow Cover

Years on Record: 35

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

Most Snow Reported in a Month

Years on Record: 46

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
in		42		17.3		16		42		22		15		1		---		---		10		17		20		24.5

Avg. No. of Days w/Snow Above 1in/2.5cm

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		13.7		1.8		2.1		2		2.1		0.5		---		---		---		0.3		1.3		2		1.6

Avg. No. of Days w/Snow Above 3in/7.5cm

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		6.4		0.8		1		1.1		0.8		0.2		---		---		---		0.2		0.8		0.8		0.7

Avg. No. of Days w/Snow Above 5in/12.7cm

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		2.4		0.1		0.5		0.4		0.2		0.1		---		---		---		0.1		0.5		0.3		0.2

Avg. No. of Days w/Snowfall Above 10in/25cm

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		0.3		---		0.1		0.1		---		---		---		---		---		---		0.1		---		---

Heating Degree Days

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		8001		1333		1118		946		672		418		145		24		38		250		637		1025		1396

Cooling Degree Days

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		383		---		---		---		---		2		40		175		142		24		---		---		---

Growing Degree Days

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		2004		---		---		4		29		131		352		617		569		254		43		5		---

Average Length of Day

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Hours		12.7		10		11.1		12.5		14		15.2		15.9		15.5		14.4		12.9		11.5		10.2		9.6

Average Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		4.3		2		2.9		4		5.1		6.2		6.9		6.8		6		4.7		3.3		2.1		1.7

Average Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		1.4		0.6		0.9		1.3		1.8		2.1		2.2		2		1.8		1.4		1		0.7		0.6

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		3.9		4.5		5		5.3		5.7		5.9		6.1		5.9		5.6		5		3.8		3.7

Average Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		5.7		4.2		4.9		5.3		5.6		6.6		7.3		7.6		7		6.3		5.4		4		3.9

Maximum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		4.3		2		2.9		4		5.1		6.2		6.9		6.8		6		4.7		3.3		2.1		1.7

Maximum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		1.5		0.7		1		1.5		1.9		2.3		2.4		2.2		1.9		1.5		1.1		0.8		0.6

Maximum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		5.8		4.8		5.6		5.9		6.5		6.5		6.7		6.6		6.4		6.2		5.5		4.7		4.7

Maximum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		7.1		5.4		6.7		6.7		7.9		8.4		9.2		9		8		7.4		6.2		5.3		5.3

Minimum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		3.8		1.7		2.4		3.4		4.5		5		5.9		6.3		5.7		4.3		3		1.8		1.4

Minimum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		1.2		0.5		0.7		1.2		1.5		1.8		1.9		1.8		1.6		1.2		0.9		0.6		0.5

Minimum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		4.3		3.2		3.6		4.1		4.6		4.6		5.1		5.6		5.7		5		4.4		3.2		2.7

Minimum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		4.4		3.2		3.5		3.9		4.4		4.3		5.4		6.5		6.4		5.3		4.5		3.2		2.7