ALTON, IOWA

Average Temperature

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		47.3		17.5		21.6		34		47.8		59.3		69		74.4		72.1		63.4		51.1		35.5		22.3

Average High Temperature

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		58.6		27.5		31.8		44.4		60.1		71.8		80.8		86.8		84.2		75.3		63.3		45.8		31.8

Average Low Temperature

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		36		7.5		11.5		23.5		35.5		46.9		57.2		62		60.1		51.4		38.9		25.1		12.7

Highest Recorded Temperature

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		110		66		65		87		95		106		104		110		107		100		93		78		63

Lowest Recorded Temperature

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
F		-42		-42		-34		-20		-9		21		32		40		33		20		-10		-12		-34

Average Number of Days Above 90F/32C

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		29.4		---		---		---		0.1		1.6		6		11.2		7.7		2.7		0.1		---		---

Average Number of Days Below 32F/0C

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		160.5		30.6		27.5		25.3		12		2.2		---		---		---		1.1		8.4		23.4		30

Average Number of Days Below 0F/-17C

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		25.3		10.3		6.7		1.2		---		---		---		---		---		---		---		0.6		6.5

Average Precipitation

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
in		26.2		0.7		0.8		1.5		2.4		3.5		4		3.4		3.4		3		1.8		1.1		0.8

Average Number of Days With Precipitation

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		83		5		4		6		8		10		10		8		9		8		6		5		4

Most Reported Precipitation in a Month

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
in		10.5		2.6		3.1		5.2		7.2		8.8		9.2		8.2		8.9		10.5		5.9		4		3.2

Least Reported Precipitation in a Month

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
in		---		---		---		---		0.4		0.3		0.6		0.2		0.3		0.5		---		---		---

Most Precipitation Reported in a Day

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
in		5.7		1.4		1.6		2.6		2		3.6		3.3		3.5		5.4		5.7		3.2		2		1.4

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		55		2.1		1.9		4.4		6		7.2		6.9		5.3		5.5		5.6		4.4		3.3		2.4

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

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		53		3		2		4		5		7		7		5		6		5		4		3		2

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

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		16		---		---		1		2		2		3		2		2		2		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		18.3		0.4		0.2		1.1		2.1		2.4		2.9		2.4		2.1		2.1		1.4		0.9		0.3

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

Years on Record: 105

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

Average Snowfall

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
in		30		6.5		5.5		6.4		1.7		0.2		---		---		---		---		0.7		3.1		5.9

Average Number of Days With Snow

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		17.1		4.2		2.9		2.6		0.9		---		---		---		---		---		0.3		2.4		3.8

Most Snow Reported in a Month

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
in		24		24		23.3		19.9		12.5		6		---		---		---		2		8		17		17.2

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		10.3		2.3		1.5		1.8		0.7		---		---		---		---		---		0.1		1.4		2.5

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		3.1		0.8		0.4		0.7		0.2		---		---		---		---		---		---		0.2		0.8

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		0.8		0.3		0.1		0.2		---		---		---		---		---		---		---		0.1		0.1

Heating Degree Days

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		4918		1163		943		657		261		60		3		---		---		30		199		588		1014

Cooling Degree Days

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		857		---		---		---		5		49		170		297		236		91		9		---		---

Growing Degree Days

Years on Record: 105

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		2735.9		---		---		---		---		288.3		570		756.4		685.1		402		34.1		---		---

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		3.8		1.8		2.6		3.5		4.6		5.5		6.1		6.2		5.4		4.2		3		1.9		1.5

Average Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		1.5		0.7		1		1.4		1.9		2.3		2.4		2.2		1.9		1.5		1.1		0.8		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		4.4		3.4		3.9		4.3		4.7		5		5.3		5.5		5.3		4.8		4.3		3.3		3.1

Average Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		4.6		3.4		3.9		4.2		4.6		5.2		5.9		6.3		5.7		5		4.4		3.4		3.2

Maximum 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		1.8		2.6		3.5		4.6		5.5		6.1		6.2		5.4		4.2		3		1.9		1.5

Maximum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		1.6		0.7		1		1.5		2		2.4		2.5		2.4		2.1		1.6		1.2		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		5.3		4		4.9		5.3		5.9		5.9		6.2		6		5.9		5.9		5.5		4.5		4

Maximum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		6.1		4.2		5.3		5.7		6.7		7		8		7.5		6.8		6.8		6.2		5.1		4.3

Minimum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		3.1		1.6		1.9		2.5		3.7		4.3		5.2		4.7		4.7		3.1		2.3		1.6		1.3

Minimum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		1.3		0.6		0.9		1.3		1.7		2.1		2.1		2.1		1.8		1.3		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		3.4		2.9		2.5		2.8		3.7		4		4.5		4.2		4.6		3.4		3		2.5		2.4

Minimum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
kWh/m2		2.9		2.8		2.1		2.1		3		3.2		4.2		3.6		4.4		2.7		2.6		2.3		2.2