Historical Climate Data

Temperature Summary
Station: 478905 WASHINGTON ISLAND 1 N, WI
1971-2000 NCDC Normals

Element	JAN	FEB	MAR	APR	MAY	JUN	JUL	AUG	SEP	OCT	NOV	DEC	ANN
Max °F	23.6	26.1	35.4	46.4	58.9	67.7	73.8	72.5	64.7	53.3	40.6	29.1	49.3
Min °F	9.2	9.8	19.9	30.7	41.0	51.0	58.3	58.0	51.4	40.7	29.5	18.3	34.8
Mean °F	16.4	18.0	27.7	38.6	50.0	59.4	66.1	65.3	58.1	47.0	35.1	23.7	42.1
HDD base 65	1508	1317	1159	794	468	194	52	77	219	557	900	1281	8526
CDD base 65	0	0	0	0	2	24	86	85	11	0	0	0	208

Temperature Extremes
Period of Record: 1948-2001

Month	High Mean°F	Year	Low Mean°F	Year	1-Day Max°F	Date	1-Day Min°F	Date
JAN	26.3	1990	6.6	1977	47	01-11-1975	-27	01-17-1982
FEB	31.6	1998	10.4	1979	52	02-23-1984	-26	02-03-1996
MAR	37.8	2000	21.3	1960	71	03-08-2000	-26	03-01-1962
APR	45.1	1955	32.5	1950	77	04-28-1951	2	04-06-1982
MAY	58.2	1998	45.1	1983	87	05-28-1969	20	05-08-1950
JUN	64.9	1987	54.8	1969	92	06-14-1987	26	06-08-1949
JUL	72.9	1955	61.5	1992	94	07-14-1983	35	07-04-1972
AUG	73.0	1955	59.1	1950	97	08-21-1955	32	08-22-1950
SEP	64.5	1998	54.6	1974	94	09-01-1953	26	09-28-1976
OCT	56.0	1963	43.1	1981	84	10-06-1963	18	10-09-1989
NOV	43.0	1999	30.1	1951	71	11-02-1990	1	11-23-1950
DEC	32.8	2001	13.5	1989	58	12-06-2001	-21	12-29-1976

Annual	48.1	1998	39.5	1972	97	08-21-1955	-27	01-17-1982
Winter	28.8	1998	12.9	1977	58	12-06-1901	-27	01-17-1982
Spring	44.4	1998	34.8	1950	87	05-28-1969	-26	03-01-1962
Summer	69.3	1955	60.1	1950	97	08-21-1955	26	06-08-1949
Fall	52.3	1998	43.3	1976	94	09-01-1953	1	11-23-1950

Temperature Threshold Climatology
Derived from 1971-2000 Averages

*Annual/seasonal totals may differ from the sum of the monthly totals due to rounding.

Month	# Days Max ≥ 90°F	# Days Max ≤ 32°F	# Days Min ≤ 32°F	# Days Min ≤ 0°F
JAN	0.0	22.6	30.7	7.0
FEB	0.0	17.3	27.4	5.9
MAR	0.0	7.8	27.5	1.4
APR	0.0	0.7	16.7	0.0
MAY	0.0	0.0	4.6	0.0
JUN	0.1	0.0	0.2	0.0
JUL	0.3	0.0	0.0	0.0
AUG	0.1	0.0	0.0	0.0
SEP	0.0	0.0	0.5	0.0
OCT	0.0	0.0	5.3	0.0
NOV	0.0	3.2	19.3	0.0
DEC	0.0	15.5	29.0	1.8

Annual	0.5	67.2	161.3	16.2
Winter	0.0	55.4	87.0	14.7
Spring	0.0	8.5	48.8	1.4
Summer	0.5	0.0	0.2	0.0
Fall	0.0	3.2	25.1	0.0