ROCK FALLS, ILLINOIS

Average Precipitation

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		957.6		35.6		35.6		63.5		99.1		116.8		109.2		109.2		116.8		86.4		73.7		66		48.3

Average Number of Days With Precipitation

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		107.9		8.6		5.9		8.1		10.8		11.8		12.3		9.7		9.3		7.5		8.4		7.8		7.7

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		70.3		4.6		3.6		4.9		7.6		7.6		8.3		7.5		6.4		5.5		4.9		4.6		4.8

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		26.3		0.7		1		1.4		3.1		3.2		3.1		3.5		3.2		2.6		1.7		1.6		1.2

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

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		10.1		0.1		0.3		0.5		1.1		1.3		1.4		1.4		1.5		1		0.7		0.3		0.5

Average Precipitable Water

Years on Record: 20

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
cm.		1.9		0.9		0.9		1.1		1.5		2.2		2.9		3.3		3.2		2.5		1.8		1.3		1

Average Snowfall

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
cm		65.8		22.1		10.9		5.6		1		---		---		---		---		---		---		2.3		23.9

Average Number of Days With Snow

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		10.9		3.9		1.9		1		0.2		---		---		---		---		---		---		0.5		3.4

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		8.5		3		1.2		0.7		0.2		---		---		---		---		---		---		0.4		3

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		3.4		1.2		0.6		0.3		0.1		---		---		---		---		---		---		0.1		1.1

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		1.3		0.5		0.2		0.1		---		---		---		---		---		---		---		---		0.5

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		0.1		---		---		---		---		---		---		---		---		---		---		---		0.1

Avg. # of Days w/Snow Depth Above 1in/2.5cm

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		32.3		14.2		7.5		2.4		0.1		---		---		---		---		---		---		0.8		7.3

Avg. # of Days w/Snow Depth Above 3in/7.5cm

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		23.7		11.3		5.4		1.7		0.1		---		---		---		---		---		---		0.3		4.9

Avg. # of Days w/Snow Depth Above 5in/12.7cm

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		15.2		7.3		3.2		0.8		---		---		---		---		---		---		---		0.1		3.8

Avg. # of Days w/Snow Depth Above 10in/25cm

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		2.6		1.2		0.1		0.1		---		---		---		---		---		---		---		---		1.2

Average Relative Humidity

Years on Record: 20

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
%		66.5		69		67.5		63.8		59.4		62.4		65.1		70.9		72.7		65.9		63.9		66.7		70.6

Average Length of Day

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Hours		12.7		10.1		11.1		12.5		13.9		15.1		15.7		15.4		14.3		12.9		11.5		10.3		9.7

Average Total Sky Cover

Years on Record: 20

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
%		50.1		63.1		62.1		55.3		51.2		47.8		40.2		38.2		37.9		37.8		44.6		57.9		64.3

Average Opaque Sky Cover

Years on Record: 20

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
%		43.4		56		53.3		50.2		45.6		42		33.6		31.3		31.2		31		38.1		51.7		57.6

Average Wind Speed

Years on Record: 20

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
km/h		12.9		14.8		14.8		15		16.4		14.1		11.1		9.6		8.6		10.1		12.5		14		14

Average Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		13.7		6.5		9.5		12.6		16.3		19.4		21.7		21.5		18.5		15.3		10.6		6.6		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		5.4		2.6		3.6		5.2		7		8.2		8.6		8.2		7.2		5.5		4.1		2.8		2.3

Average Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		15.4		11.9		14.2		15.1		16.7		17.8		18.9		19.1		18.2		17.5		14.7		10.7		10.5

Average Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		15.7		12.1		14.4		14.4		15.9		17.8		20.3		20.8		18.6		18.1		14.6		10.8		10.7

Maximum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		13.7		6.5		9.5		12.6		16.3		19.4		21.7		21.5		18.5		15.3		10.6		6.6		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		5.7		2.6		3.8		5.4		7.1		8.5		9		8.7		7.6		6		4.3		3		2.3

Maximum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		19.1		14.8		18.2		21.9		19.6		22.9		21.9		21.2		20.7		22.4		17.8		15.3		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		22		15.8		19.9		25.3		21		28.8		27.3		25.4		23.5		26.5		19		17		14.4

Minimum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		10.7		5.7		6.5		9.7		12.8		14.7		18.9		16.2		15.9		11.2		8.1		4.4		4.2

Minimum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		4.8		2.3		3.1		4.1		6.5		6.8		7.7		7.7		6.7		4.4		3.7		2.6		2.1

Minimum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		11.4		9.7		8.8		10.9		12.8		13.4		16.5		14.5		15.4		12		10.2		6		7.1

Minimum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		9.5		9.2		6.9		8.5		9.7		10		15.4		11.7		13.7		9.6		8.6		4.8		6.4