DILLON, MONTANA

Average Temperature

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		3.4		-12.8		-6.4		-1.3		4.4		8.1		12.4		16.4		16.1		9.7		5.1		-3.7		-7.6

Average High Temperature

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		12.9		-4.2		1.4		6.6		13.3		17.3		22.6		28.7		27.3		20.2		15.4		5.7		1.2

Average Low Temperature

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		-6.2		-21.3		-14.2		-9.1		-4.5		-1.2		2.3		4.2		4.8		-0.8		-5.3		-13		-16.3

Highest Recorded Temperature

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		38.9		8.9		11.7		18.3		24.4		28.3		32.2		38.9		35.6		29.4		23.9		16.7		15.6

Lowest Recorded Temperature

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		-46.7		-46.7		-40		-27.2		-12.2		-9.4		-5		-5.6		-5		-10		-14.4		-28.9		-28.9

Average Number of Days Above 90F/32C

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		8.7		---		---		---		---		---		0.3		6		2.3		---		---		---		---

Average Number of Days Below 32F/0C

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		255.8		31		28		30.3		27.3		20		8.3		4.7		3.3		17.5		25		29.7		30.7

Average Number of Days Below 0F/-17C

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		51.7		18.7		7.3		4		---		---		---		---		---		---		---		7.3		14.3

Average Precipitation

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		245		9		7		14		23		41		43		22		23		24		18		12		10

Average Number of Days With Precipitation

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		82		6		5		7		8		10		9		6		7		6		6		6		6

Most Reported Precipitation in a Month

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		116		30		25		56		69		116		112		98		79		74		59		33		26

Least Reported Precipitation in a Month

Years on Record: 83

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

Most Precipitation Reported in a Day

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		49.3		12.9		11.4		31.8		36.8		32.3		36.1		34.3		27.4		49.3		25.9		12.9		17.5

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

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		32		1		1		2		3		5		5		3		3		3		3		2		1

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

Years on Record: 83

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

Average Number of Rainy Days

Years on Record: 21

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		24		1		1		1		2		4		4		2		1		2		1		1		1

Average Snowfall

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
cm		104.4		14.2		10.2		17.8		19.3		7.6		0.5		---		---		2.3		7.1		12.2		13.2

Most Snow Reported in a Month

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
cm		88.9		42.9		35.3		77.2		88.9		58.4		18		---		---		22.9		37.1		39.4		36.3

Average Relative Humidity

Years on Record: 12

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
%		59		67		66		65		58		58		56		47		48		53		57		64		67

Average Dew Point

Years on Record: 12

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		-2		-12		-10		-8		-4		1		4		6		5		1		-2		-7		-9

Heating Degree Days

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		3690.6		792.8		537.2		436.1		251.7		150		42.8		5		5		105.6		241.1		492.8		630.6

Cooling Degree Days

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		21.1		---		---		---		---		---		0.6		15.6		5		---		---		---		---

Growing Degree Days

Years on Record: 83

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		459.1		---		---		---		---		---		73.3		198.1		187.7		---		---		---		---

Average Length of Day

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Hours		12.8		9.8		11		12.5		14.1		15.5		16.2		15.8		14.5		13		11.4		10		9.4

Average Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		14.9		6.3		9.8		14.4		18.2		20.8		23		24.7		21.5		16.7		11.1		6.9		5.5

Average Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		4.8		2		3		4.4		6.3		7.8		8.2		7.2		6.1		4.7		3.4		2.3		1.8

Average Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		17.9		13.6		16.7		19.4		19.3		19.1		20		22		21.6		20.3		17		13.5		11.9

Average Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		20.2		14.3		18		20.7		21.1		21.2		23.7		28.2		26.1		23.1		18.4		14.2		13.7

Maximum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		14.9		6.3		9.8		14.4		18.2		20.8		23		24.7		21.5		16.7		11.1		6.9		5.5

Maximum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		5.3		2.2		3.2		4.9		6.7		8.2		8.9		8.3		6.7		5.6		3.8		2.5		1.9

Maximum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		20.6		15.3		18.4		22.5		22.2		22.1		22.5		24.9		23.9		23.6		22.4		16.5		13.2

Maximum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		25.2		16.4		20.6		25.9		26.6		27.7		29.7		35.8		31.1		29		26.2		18		15.7

Minimum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		13		5.9		8.6		12.4		16.5		18.7		19.9		20.6		19.8		13.4		9.7		5.7		5

Minimum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		4.1		1.9		2.7		3.7		5.5		7		7.4		5.8		5.3		3.8		2.6		2.1		1.6

Minimum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		15.2		12.2		13.9		16.2		17.2		17.2		17.3		18.4		19.8		15.4		14.2		10.3		10.2

Minimum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		15.6		12.5		14		15.6		17.3		17.2		17.5		19.8		22.4		15		14.3		10		11.3