Historical Climate Data

Temperature Summary
Station: 470045 AFTON, WI

1971-2000 NCDC Normals

 ElementJAN  FEB  MAR  APR MAY  JUN  JUL  AUG SEP  OCT  NOV  DEC ANN
 Max °F 26.7 32.0 44.7 57.970.8 80.6 83.8 81.374.1 61.3 45.1 31.457.5
 Min °F 8.6  13.6 25.2 35.346.6 55.6 60.4 58.148.8 37.9 27.6 15.336.1
 Mean °F17.7 22.8 35.0 46.658.7 68.1 72.1 69.761.5 49.6 36.4 23.446.8
 HDD
 base 651469 1181 933  554 242  39   8    35  144  482  859  12927238
 CDD
 base 650    0    0    1   48   131  228  181 37   3    0    0   629

Temperature Extremes
Period of Record: 1987-2001

       High        Low        1-Day            1-Day
 Month Mean°F Year Mean°F YearMax°F Date       Min°F Date
 JAN   28.9   1990 9.5    199459    01-31-1989 -28   01-19-1994
 FEB   35.2   1998 13.0   198969    02-26-2000 -31   02-03-1996
 MAR   42.0   2000 28.4   199680    03-30-1998 -3    03-08-1996
 APR   51.5   2001 42.6   199585    04-25-1990 15    04-05-1995
 MAY   64.1   1991 52.7   199792    05-31-1988 27    05-06-1989
 JUN   71.5   1991 65.3   1992101   06-20-1988 36    06-01-1993
 JUL   76.4   1999 67.4   1992101   07-15-1988 45    07-02-2001
 AUG   76.9   1995 64.0   1992102   08-01-1988 43    08-16-1992
 SEP   65.3   1998 56.5   199396    09-02-2000 28    09-23-1995
 OCT   53.7   2000 42.3   198788    10-06-1997 14    10-29-1988
 NOV   46.2   2001 28.4   199574    11-09-1999 -4    11-29-1995
 DEC   31.5   2001 11.4   200067    12-06-2001 -25   12-25-2000

 Annual51.0   1998 44.6   1996102   08-01-1988 -31   02-03-1996
 Winter29.6   1998 16.3   199469    02-26-1900 -31   02-03-1996
 Spring50.3   1991 41.8   199692    05-31-1988 -3    03-08-1996
 Summer74.1   1995 65.6   1992102   08-01-1988 36    06-01-1993
 Fall  52.8   1998 46.1   199596    09-02-1900 -4    11-29-1995

Temperature Threshold Climatology
Derived from 1987-2000 Averages

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

       # Days     # Days     # Days     # Days
 Month Max ? 90°F Max ? 32°F Min ? 32°F Min ? 0°F
 JAN   0.0        19.1       30.0       8.1
 FEB   0.0        13.0       26.2       5.2
 MAR   0.0        4.5        24.9       0.3
 APR   0.0        0.2        11.9       0.0
 MAY   0.2        0.0        1.0        0.0
 JUN   3.7        0.0        0.0        0.0
 JUL   5.8        0.0        0.0        0.0
 AUG   3.4        0.0        0.0        0.0
 SEP   1.2        0.0        0.9        0.0
 OCT   0.0        0.0        10.9       0.0
 NOV   0.0        4.2        22.2       0.2
 DEC   0.0        15.0       29.4       4.4

 Annual14.3       55.6       157.6      18.1
 Winter0.0        47.0       85.6       17.6
 Spring0.2        4.8        37.8       0.3
 Summer12.8       0.0        0.0        0.0
 Fall  1.2        4.0        33.2       0.1