CASTLE TOWN, MONTANA

Average Temperature

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		5.7		-5.2		-3.6		0.4		4.9		9.6		13.9		18.3		17.6		12.1		6.3		-0.7		-5.5

Average High Temperature

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		12.9		0.3		2.5		6.8		12.2		17.3		21.8		27.6		27.1		20.8		13.8		4.9		---

Average Low Temperature

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		-1.6		-10.9		-9.6		-6.1		-2.4		1.8		6		9.1		8.2		3.5		-1.1		-6.4		-11

Highest Recorded Temperature

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		37.2		15		16.7		22.2		27.2		30.6		36.1		37.2		36.7		33.9		30		20.6		14.4

Lowest Recorded Temperature

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		-43.3		-38.3		-41.7		-30.6		-18.9		-8.9		-5		0.6		-5		-11.1		-27.8		-34.4		-43.3

Average Number of Days Above 90F/32C

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		8.8		---		---		---		---		---		0.7		4.4		3.5		0.2		---		---		---

Average Number of Days Below 32F/0C

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		195.6		29.2		26.2		27.2		22.3		11		1.4		---		0.4		5.5		18.2		24.7		29.4

Average Number of Days Below 0F/-17C

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		21.2		6.7		4		1.7		0.1		---		---		---		---		---		0.3		2.5		5.9

Average Precipitation

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		326		11		9		18		31		54		62		39		28		28		21		12		12

Average Number of Days With Precipitation

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		88		5		4		6		8		11		12		9		8		7		7		5		6

Most Reported Precipitation in a Month

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		142		27		31		51		101		129		128		142		83		80		48		38		45

Least Reported Precipitation in a Month

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		---		---		---		1		2		13		15		6		1		1		2		---		1

Most Precipitation Reported in a Day

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		65		15		27.4		20.3		65		50.8		57.7		53.9		31		36.6		23.6		19.6		17

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

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		39		1		1		3		4		5		7		5		4		3		3		1		2

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

Years on Record: 33

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

Average Snowfall

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
cm		99.1		16		16.3		19.6		9.1		2.3		---		---		---		2.3		5.6		10.7		17.3

Average Snow Cover

Years on Record: 21

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

Most Snow Reported in a Month

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
cm		97.3		56.9		61		97.3		53.3		19.1		---		---		---		33		29.2		37.9		53.6

Heating Degree Days

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		4777.8		753.9		612.8		562.8		406.1		273.9		140		68.3		75.6		200		370.6		583.3		730.6

Cooling Degree Days

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		100		---		---		---		---		---		10		42.8		40		7.2		---		---		---

Growing Degree Days

Years on Record: 33

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		672.5		---		---		---		---		---		116.7		256.6		235.9		63.3		---		---		---

Average Length of Day

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Hours		12.8		9.7		10.9		12.5		14.2		15.7		16.4		16		14.6		13		11.4		9.9		9.2

Average Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		13.6		5		8.3		12.4		16.7		20.1		22.2		23.7		20.1		15		9.7		5.7		4.3

Average Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		6.2		3		4.3		6.2		7.6		8.9		9.4		9.2		8		6.7		4.8		3.2		2.6

Average Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		15.1		8.7		12.6		15.3		17.4		18.4		19.3		21.1		20		17.4		13.2		9.4		7.6

Average Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		14.8		7.6		11.2		13.4		16.5		18.6		20.9		23.8		21		16.7		12.5		8.2		6.8

Maximum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		13.6		5		8.3		12.4		16.7		20.1		22.2		23.7		20.1		15		9.7		5.7		4.3

Maximum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		6.5		3.2		4.6		6.7		7.7		9.1		9.6		10.2		8.5		7.5		5.1		3.5		2.8

Maximum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		17.3		10		14		18.4		19.9		21.1		21.8		24.1		22.5		21.5		14.9		10.6		8.6

Maximum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		17.9		8.9		13		17.4		20.6		23.4		25.7		27.8		24.4		21.6		14.4		9.5		8.1

Minimum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		11.5		4.3		7.2		10.2		14.8		17.2		18.8		18.2		18.1		12.1		8.6		4.9		3.6

Minimum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		5.9		2.6		3.9		5.7		7.5		8.8		9.3		9		7.9		6.2		4.4		2.9		2.3

Minimum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		12.5		7.2		10.8		12.2		15.1		15.7		16.3		16.2		17.9		13.5		11.6		7.7		6.2

Minimum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		11.1		6.1		9.2		9.7		12.8		13.5		15		14.7		17.6		11.8		10.7		6.6		5.3