OKLAHOMA CITY - LAKE HEFNER, OKLAHOMA

Average Temperature

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		15.8		3.4		5.7		10.3		15.3		20.6		25.1		28.1		27.6		22.9		16.3		9.8		4.1

Average High Temperature

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		21.8		9.3		11.9		16.6		21.5		26.4		30.9		34		33.6		28.7		22.4		15.6		9.7

Average Low Temperature

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		9.8		-2.5		-0.6		4		9.1		14.7		19.4		22.2		21.5		17.1		10.1		3.9		-1.6

Highest Recorded Temperature

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		37.6		13		17.5		19.1		24.9		28		32.2		37.6		37.4		32		25.6		20.4		13.6

Lowest Recorded Temperature

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
C		-8.9		-8.9		-5.8		0.2		5.6		11.1		16.4		19.2		17.4		12.7		5.8		-0.4		-7.4

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		10.5		---		---		---		---		---		0.7		4.9		4.2		0.7		---		---		---

Average Number of Days Above 90F/32C

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		62.5		---		---		0.1		0.4		2.6		10.1		21.7		20.7		6.7		0.3		---		---

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		136		---		0.3		1.5		5.2		15.3		26.1		30.1		29.4		20.1		7.4		0.7		---

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		203.2		0.9		2.6		8.7		17		27.5		29.9		31		30.9		28.2		19.1		6.5		0.8

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		260.4		6.3		8.7		18.4		25.4		30.8		30		31		31		29.8		27.8		14.8		6.4

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		311.4		15.1		17.5		26.1		29.5		31		30		31		31		30		30.5		23.9		15.8

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		342.7		22.7		23.1		29.9		30		31		30		31		31		30		31		29		24

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		308		31		28		31		29.9		29.2		20.6		9		12.6		24.9		30.7		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		236.2		31		28		30.3		26.8		17.5		4		0.4		0.9		10.3		26.7		29.5		30.9

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		179.7		30.5		27.4		26.6		16.8		4.8		0.1		---		---		2		15.4		25.8		30.4

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		123.6		28		23.3		16.8		5.8		---		---		---		---		0.1		4.6		17.5		27.5

Average Number of Days Below 32F/0C

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		72.6		21.1		16.5		7.2		1.2		---		---		---		---		---		0.3		7.2		19.2

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		15.5		6.5		2.8		0.9		---		---		---		---		---		---		---		0.3		5.1

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		1.8		1		0.4		---		---		---		---		---		---		---		---		---		0.5

Average Number of Days Below 0F/-17C

Years on Record: 27

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

Average Precipitation

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		823		17.8		30.5		71.1		73.7		104.1		119.4		68.6		83.8		86.4		83.8		45.7		38.1

Average Number of Days With Precipitation

Years on Record: 27

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		75		4		5		6		7		9		8		7		6		7		6		5		5

Most Reported Precipitation in a Month

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		361		212		189		231		261		303		360		170		147		320		361		276		244

Least Reported Precipitation in a Month

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		---		1		1		15		21		34		12		3		---		5		12		1		---

Most Precipitation Reported in a Day

Years on Record: 27

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
mm		139.7		53.3		39.6		48		100.8		71.9		82.5		74.4		64.3		130.6		106.2		139.7		65.5

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

Years on Record: 27

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		49		2		3		4		5		6		6		5		4		5		4		3		2

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

Years on Record: 27

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		21		1		1		1		2		3		3		2		2		2		2		1		1

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

Years on Record: 27

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		8		---		---		---		1		2		1		1		1		1		1		---		---

Average Precipitable Water

Years on Record: 20

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
cm.		2.2		1.1		1.1		1.4		1.7		2.5		3.3		3.7		3.7		3		2		1.4		1.1

Average Snowfall

Years on Record: 27

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
cm		17.5		3.8		5.6		3.3		0.2		---		---		---		---		---		---		1		3.6

Most Snow Reported in a Month

Years on Record: 27

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
cm		35.6		20.1		23.6		35.6		5.1		---		---		---		---		---		---		11.4		10.7

Average Relative Humidity

Years on Record: 20

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
%		64.1		64.4		62.1		61.6		62.2		68.5		67.2		60.6		60.9		65.4		65		65.1		65.6

Heating Degree Days

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		3635		834		638		456		205		40		1		---		---		19		176		468		797

Cooling Degree Days

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		1969		---		1		8		40		166		368		544		513		264		60		4		---

Growing Degree Days

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Days		5075		15		36		134		305		591		817		1009		978		694		361		114		21

Average Length of Day

Years on Record: 30

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Hours		12.6		10.5		11.4		12.4		13.6		14.5		15		14.8		13.9		12.8		11.7		10.7		10.3

Average Total Sky Cover

Years on Record: 20

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
%		38.6		45.1		48.2		46.4		43		46.1		36.7		25.8		27.1		31.3		34.5		38.4		40.1

Average Opaque Sky Cover

Years on Record: 20

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
%		34.7		42		43.6		42.5		38.6		40.8		31.7		21.7		22.6		28.9		31.9		35.8		37.3

Average Wind Speed

Years on Record: 20

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
km/h		19		18.7		19.3		21.3		22.1		19.8		19.4		18.3		16.6		16.7		18.4		19		18.3

Average Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		16.1		9		11.6		15.3		19.3		21.3		22.8		24.2		20.7		17.2		13.2		9.9		8.1

Average Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		5.7		3.1		4.2		5.6		7		8.1		8.5		7.7		7.2		5.9		4.5		3.3		2.8

Average Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		17.6		14		15.1		17.6		19.4		19.5		19.9		21.5		20		18.9		17.1		14.6		13.1

Average Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		18.5		15.1		15.7		17.4		19.7		20		21.4		24.8		21		19.3		17.5		15.8		14.1

Maximum Daily Solar Radiation - Global

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		16.1		9		11.6		15.3		19.3		21.3		22.8		24.2		20.7		17.2		13.2		9.9		8.1

Maximum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		6.1		3.4		4.5		6		7.5		8.7		9.1		8.3		7.7		6.5		5		3.7		3.1

Maximum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		21.2		19		20.3		22		23.2		21.8		22		23.5		22		22.2		21.6		19.8		16.7

Maximum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		24.8		22.8		24.1		24.6		27		24.8		26.2		29.6		24.9		25.3		24.5		23.9		19.5

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		7.1		9.2		12.8		16.8		17.2		19.4		22		18.6		14.5		10.3		7.3		6.2

Minimum Daily Solar Radiation - Diffuse

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		4.9		2.3		3.2		4.7		5.9		7.5		7.8		6.9		6.6		5		3.6		2.5		2.4

Minimum Daily Solar Radiation - Reflected

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		14.1		10		11.2		14.3		16.8		15.8		17.2		19.6		17.9		15.4		12.5		9.7		8.9

Minimum Daily Solar Radiation - Direct

Years on Record: 22

		ANNUAL		JAN		FEB		MAR		APR		MAY		JUN		JUL		AUG		SEP		OCT		NOV		DEC
Mj/m2		12.8		9.4		9.9		12.3		14.9		13		15.5		20.6		16.9		13.6		10.7		8.7		8.3