Record envelope, standing records and threshold days for Janesville (USC00473979), Wisconsin, United States, with 95 years of record.
Key Facts for Janesville
Janesville (USC00473979) is a weather station in Wisconsin, United States at 42.67 latitude and -89.02 longitude, 232 m (761 ft) above sea level.
The station reports from 1893 to 1987, 95 years of record.
1,464 records set at Janesville still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Janesville set a daily record high maximum temperature of 10.0 C (50.0 F) on 7 February 1987.
About the Station
Location: Wisconsin, United States, 42.67 latitude, -89.02 longitude.
Elevation: 232 m (761 ft).
Period of record: 1893 to 1987, 95 years.
Eligible elements: tmax, tmin, prcp, snow, snwd.
Daily Record Envelope and 2026
0 days at or beyond a record
Record highRecord low2026 daily maximum2026 daily minimum
The band shows the record high and record low for each calendar day at Janesville. The lines show the 2026 daily maximum and minimum. 0 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.
Daily record high and record low at Janesville, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
15.6 C (60.1 F)
-33.3 C (-27.9 F)
n/a
n/a
Feb
18.3 C (64.9 F)
-31.1 C (-24.0 F)
n/a
n/a
Mar
28.3 C (82.9 F)
-25.0 C (-13.0 F)
n/a
n/a
Apr
32.8 C (91.0 F)
-15.0 C (5.0 F)
n/a
n/a
May
35.0 C (95.0 F)
-8.3 C (17.1 F)
n/a
n/a
Jun
37.8 C (100.0 F)
0.0 C (32.0 F)
n/a
n/a
Jul
38.9 C (102.0 F)
5.0 C (41.0 F)
n/a
n/a
Aug
37.8 C (100.0 F)
4.4 C (39.9 F)
n/a
n/a
Sep
38.3 C (100.9 F)
-2.8 C (27.0 F)
n/a
n/a
Oct
31.7 C (89.1 F)
-11.7 C (10.9 F)
n/a
n/a
Nov
25.6 C (78.1 F)
-27.2 C (-17.0 F)
n/a
n/a
Dec
18.3 C (64.9 F)
-31.7 C (-25.1 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Janesville still stand. 1895 holds the most, with 75.
Standing records at Janesville by the year they were set
Year set
Standing records
1893
45
1894
52
1895
75
1915
4
1916
7
1917
6
1944
7
1945
48
1946
33
1947
50
1948
17
1949
31
1950
42
1951
40
1952
29
1953
35
1954
31
1955
33
1956
30
1957
15
1958
26
1959
32
1960
32
1961
17
1962
33
1963
40
1964
39
1965
41
1966
27
1967
36
1968
27
1969
21
1970
21
1971
28
1972
25
1973
28
1974
27
1975
28
1976
40
1977
40
1978
17
1979
23
1980
11
1981
25
1982
29
1983
41
1984
26
1985
24
1986
26
1987
4
All-Time Record Progression
9 new records
9 all-time records were set at Janesville between 15 January 1972 and 20 January 1985. Each dot is a new record.
When Janesville set new all-time records
Date
Kind
Detail
1972-01-15
Record low maximum temperature
Record low maximum temperature -22.2 C (-8.0 F)
1973-08-27
Record high minimum temperature
Record high minimum temperature 26.1 C (79.0 F)
1979-01-13
Record snow depth
Record snow depth 63.5 cm (25.0 in)
1979-01-14
Record snow depth
Record snow depth 66.0 cm (26.0 in)
1979-01-15
Record snow depth
Record snow depth 71.1 cm (28.0 in)
1979-01-19
Record snow depth
Record snow depth 78.7 cm (31.0 in)
1979-01-23
Record snow depth
Record snow depth 83.8 cm (33.0 in)
1979-01-24
Record snow depth
Record snow depth 91.4 cm (36.0 in)
1985-01-20
Record low maximum temperature
Record low maximum temperature -22.8 C (-9.0 F)
Wettest Day of Each Month
Sep: 113.8 mm (4.5 in)
The wettest day on record for each calendar month at Janesville. The most was 113.8 mm (4.5 in) on 13 September 1961.
Record daily precipitation for each month at Janesville
Month
Record daily precipitation (mm)
Date
Jan
44.7 mm (1.8 in)
12 January 1960
Feb
42.7 mm (1.7 in)
22 February 1981
Mar
49.3 mm (1.9 in)
19 March 1948
Apr
47.5 mm (1.9 in)
14 April 1974
May
82.6 mm (3.3 in)
10 May 1948
Jun
73.4 mm (2.9 in)
30 June 1955
Jul
87.1 mm (3.4 in)
2 July 1962
Aug
102.1 mm (4.0 in)
4 August 1952
Sep
113.8 mm (4.5 in)
13 September 1961
Oct
55.9 mm (2.2 in)
9 October 1958
Nov
67.8 mm (2.7 in)
1 November 1984
Dec
46.0 mm (1.8 in)
15 December 1971
Period of Record Coverage
1893 to 1987
Complete yearUnder 90 percent of days
50 years of record at Janesville, 1893 to 1987. 8 years have data for under 90 percent of days and are left out of rankings: 1895, 1915, 1916, 1917, 1944, 1981, 1983, 1987.
Cooler than the station meanWarmer than the station mean
One stripe for each of 38 complete years at Janesville, 1893 to 1985. Blue stripes are years cooler than the station's own mean of 9.1 C (48.3 F); red stripes are warmer. The coolest year was 1893, at 6.4 C (43.5 F), and the warmest was 1946, at 10.4 C (50.7 F). The strongest colour marks a difference of 2.7 C (4.9 F).
Annual mean temperature at Janesville as warming stripes, 1893 to 1985
Year
Annual mean temperature
Difference from the station mean
1893
6.4 C
-2.65 C
1894
9.1 C
+0.00 C
1945
8.9 C
-0.16 C
1946
10.4 C
+1.34 C
1947
9.0 C
-0.10 C
1948
9.2 C
+0.10 C
1949
9.6 C
+0.50 C
1950
7.8 C
-1.31 C
1951
7.7 C
-1.41 C
1952
9.6 C
+0.49 C
1953
10.3 C
+1.23 C
1954
10.1 C
+0.99 C
1955
9.7 C
+0.59 C
1956
9.7 C
+0.59 C
1957
9.3 C
+0.23 C
1958
8.8 C
-0.30 C
1959
9.0 C
-0.09 C
1960
8.8 C
-0.23 C
1961
9.5 C
+0.42 C
1962
8.9 C
-0.12 C
1963
9.0 C
-0.05 C
1964
10.0 C
+0.90 C
1965
9.2 C
+0.16 C
1966
8.9 C
-0.18 C
1967
8.5 C
-0.53 C
1968
9.6 C
+0.54 C
1969
8.9 C
-0.18 C
1970
9.2 C
+0.14 C
1971
9.5 C
+0.47 C
1972
8.3 C
-0.78 C
1973
10.4 C
+1.30 C
1974
9.3 C
+0.20 C
1977
8.9 C
-0.14 C
1978
8.3 C
-0.80 C
1979
8.3 C
-0.77 C
1980
9.1 C
+0.06 C
1984
9.1 C
+0.08 C
1985
8.5 C
-0.60 C
The fitted trend in annual mean temperature here over 1893 to 1985 is 0.10 C (-0.04 to 0.23) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: 0.2 F (-0.1 to 0.4) per decade. The slope is a straight line fitted to 38 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Janesville
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.10 C (-0.04 to 0.23) per decade
0.2 F (-0.1 to 0.4) per decade
1893 to 1985
38
Not clearly different from zero
Mean daily maximum
0.03 C (-0.11 to 0.18) per decade
0.1 F (-0.2 to 0.3) per decade
1893 to 1985
38
Not clearly different from zero
Mean daily minimum
0.16 C (0.02 to 0.31) per decade
0.29 F (0.03 to 0.55) per decade
1893 to 1985
38
Rise
A year is complete when all 12 months have at least 20 days of both daily maximum and daily minimum readings. The annual mean is the mean of the monthly means. The trend describes this one station over this period; it does not say what caused the change.
Extremes by Year
1893 to 1987
Yearly extremes at Janesville: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
38.9 C (102.0 F)
1963
35.6 C (96.1 F)
50
Coldest night (TNn)
-33.3 C (-27.9 F)
1951
-26.1 C (-15.0 F)
50
Wettest day (Rx1day)
113.8 mm (4.5 in)
1961
50.6 mm (2.0 in)
50
Wettest five days (Rx5day)
173.0 mm (6.8 in)
1961
80.1 mm (3.2 in)
50
Longest dry spell (CDD)
45 days
1893
23 days
50
Hottest day (TXx)
The hottest day of the year at Janesville, 1893 to 1987. The record is 38.9 C (102.0 F) in 1963, marked on the chart; the median year is 35.6 C (96.1 F).
Hottest day (TXx) at Janesville by year
Year
Hottest day (TXx)
1893
33.9 C (93.0 F)
1894
37.8 C (100.0 F)
1895
36.1 C (97.0 F)
1915
30.6 C (87.1 F)
1916
31.7 C (89.1 F)
1917
35.6 C (96.1 F)
1944
33.3 C (91.9 F)
1945
36.7 C (98.1 F)
1946
35.6 C (96.1 F)
1947
37.8 C (100.0 F)
1948
37.8 C (100.0 F)
1949
36.1 C (97.0 F)
1950
32.8 C (91.0 F)
1951
32.8 C (91.0 F)
1952
35.6 C (96.1 F)
1953
38.3 C (100.9 F)
1954
36.7 C (98.1 F)
1955
38.3 C (100.9 F)
1956
36.1 C (97.0 F)
1957
34.4 C (93.9 F)
1958
35.0 C (95.0 F)
1959
35.0 C (95.0 F)
1960
35.6 C (96.1 F)
1961
35.0 C (95.0 F)
1962
35.0 C (95.0 F)
1963
38.9 C (102.0 F)
1964
37.8 C (100.0 F)
1965
38.3 C (100.9 F)
1966
38.9 C (102.0 F)
1967
33.3 C (91.9 F)
1968
35.0 C (95.0 F)
1969
33.9 C (93.0 F)
1970
35.6 C (96.1 F)
1971
35.6 C (96.1 F)
1972
34.4 C (93.9 F)
1973
35.0 C (95.0 F)
1974
37.2 C (99.0 F)
1975
35.0 C (95.0 F)
1976
37.8 C (100.0 F)
1977
37.2 C (99.0 F)
1978
37.2 C (99.0 F)
1979
33.9 C (93.0 F)
1980
36.1 C (97.0 F)
1981
36.7 C (98.1 F)
1982
34.4 C (93.9 F)
1983
37.8 C (100.0 F)
1984
35.6 C (96.1 F)
1985
36.1 C (97.0 F)
1986
35.6 C (96.1 F)
1987
10.0 C (50.0 F)
Coldest night (TNn)
The coldest night of the year at Janesville, 1893 to 1987. The record is -33.3 C (-27.9 F) in 1951, marked on the chart; the median year is -26.1 C (-15.0 F).
Coldest night (TNn) at Janesville by year
Year
Coldest night (TNn)
1893
-26.7 C (-16.1 F)
1894
-21.1 C (-6.0 F)
1895
-31.1 C (-24.0 F)
1915
4.4 C (39.9 F)
1916
-2.8 C (27.0 F)
1917
0.0 C (32.0 F)
1944
-27.2 C (-17.0 F)
1945
-25.6 C (-14.1 F)
1946
-22.8 C (-9.0 F)
1947
-27.2 C (-17.0 F)
1948
-26.1 C (-15.0 F)
1949
-26.7 C (-16.1 F)
1950
-31.7 C (-25.1 F)
1951
-33.3 C (-27.9 F)
1952
-24.4 C (-11.9 F)
1953
-20.0 C (-4.0 F)
1954
-24.4 C (-11.9 F)
1955
-25.0 C (-13.0 F)
1956
-22.2 C (-8.0 F)
1957
-23.3 C (-9.9 F)
1958
-25.0 C (-13.0 F)
1959
-30.0 C (-22.0 F)
1960
-25.6 C (-14.1 F)
1961
-23.3 C (-9.9 F)
1962
-26.1 C (-15.0 F)
1963
-31.1 C (-24.0 F)
1964
-20.0 C (-4.0 F)
1965
-28.3 C (-18.9 F)
1966
-28.9 C (-20.0 F)
1967
-27.8 C (-18.0 F)
1968
-27.2 C (-17.0 F)
1969
-24.4 C (-11.9 F)
1970
-27.2 C (-17.0 F)
1971
-25.6 C (-14.1 F)
1972
-27.8 C (-18.0 F)
1973
-24.4 C (-11.9 F)
1974
-26.7 C (-16.1 F)
1975
-24.4 C (-11.9 F)
1976
-26.1 C (-15.0 F)
1977
-30.6 C (-23.1 F)
1978
-23.9 C (-11.0 F)
1979
-30.6 C (-23.1 F)
1980
-22.8 C (-9.0 F)
1981
-23.3 C (-9.9 F)
1982
-32.2 C (-26.0 F)
1983
-30.6 C (-23.1 F)
1984
-28.9 C (-20.0 F)
1985
-32.8 C (-27.0 F)
1986
-26.7 C (-16.1 F)
1987
-22.8 C (-9.0 F)
Wettest day (Rx1day)
The wettest day of the year at Janesville, 1893 to 1987. The record is 113.8 mm (4.5 in) in 1961, marked on the chart; the median year is 50.6 mm (2.0 in).
Wettest day (Rx1day) at Janesville by year
Year
Wettest day (Rx1day)
1893
40.6 mm (1.6 in)
1894
68.6 mm (2.7 in)
1895
27.9 mm (1.1 in)
1915
23.9 mm (0.9 in)
1916
24.9 mm (1.0 in)
1917
39.4 mm (1.6 in)
1944
62.0 mm (2.4 in)
1945
32.3 mm (1.3 in)
1946
31.2 mm (1.2 in)
1947
82.6 mm (3.3 in)
1948
82.6 mm (3.3 in)
1949
43.2 mm (1.7 in)
1950
88.9 mm (3.5 in)
1951
41.1 mm (1.6 in)
1952
102.1 mm (4.0 in)
1953
39.4 mm (1.6 in)
1954
52.3 mm (2.1 in)
1955
73.4 mm (2.9 in)
1956
32.5 mm (1.3 in)
1957
45.7 mm (1.8 in)
1958
55.9 mm (2.2 in)
1959
59.4 mm (2.3 in)
1960
51.1 mm (2.0 in)
1961
113.8 mm (4.5 in)
1962
87.1 mm (3.4 in)
1963
70.1 mm (2.8 in)
1964
46.7 mm (1.8 in)
1965
63.5 mm (2.5 in)
1966
43.2 mm (1.7 in)
1967
50.0 mm (2.0 in)
1968
36.3 mm (1.4 in)
1969
46.7 mm (1.8 in)
1970
67.3 mm (2.6 in)
1971
46.0 mm (1.8 in)
1972
71.9 mm (2.8 in)
1973
44.7 mm (1.8 in)
1974
53.6 mm (2.1 in)
1975
48.0 mm (1.9 in)
1976
38.1 mm (1.5 in)
1977
34.0 mm (1.3 in)
1978
61.0 mm (2.4 in)
1979
70.9 mm (2.8 in)
1980
80.0 mm (3.1 in)
1981
92.2 mm (3.6 in)
1982
58.9 mm (2.3 in)
1983
40.9 mm (1.6 in)
1984
70.4 mm (2.8 in)
1985
60.7 mm (2.4 in)
1986
39.9 mm (1.6 in)
1987
6.6 mm (0.26 in)
Wettest five days (Rx5day)
The wettest five days of the year at Janesville, 1893 to 1987. The record is 173.0 mm (6.8 in) in 1961, marked on the chart; the median year is 80.1 mm (3.2 in).
Wettest five days (Rx5day) at Janesville by year
Year
Wettest five days (Rx5day)
1893
66.6 mm (2.6 in)
1894
77.7 mm (3.1 in)
1895
74.9 mm (2.9 in)
1915
58.3 mm (2.3 in)
1916
32.6 mm (1.3 in)
1917
64.8 mm (2.6 in)
1944
75.7 mm (3.0 in)
1945
56.9 mm (2.2 in)
1946
58.2 mm (2.3 in)
1947
94.8 mm (3.7 in)
1948
112.9 mm (4.4 in)
1949
74.1 mm (2.9 in)
1950
142.7 mm (5.6 in)
1951
88.6 mm (3.5 in)
1952
104.6 mm (4.1 in)
1953
76.5 mm (3.0 in)
1954
101.1 mm (4.0 in)
1955
76.2 mm (3.0 in)
1956
82.6 mm (3.3 in)
1957
54.3 mm (2.1 in)
1958
84.1 mm (3.3 in)
1959
105.8 mm (4.2 in)
1960
90.5 mm (3.6 in)
1961
173.0 mm (6.8 in)
1962
88.4 mm (3.5 in)
1963
86.3 mm (3.4 in)
1964
56.1 mm (2.2 in)
1965
98.1 mm (3.9 in)
1966
69.3 mm (2.7 in)
1967
89.1 mm (3.5 in)
1968
77.2 mm (3.0 in)
1969
68.1 mm (2.7 in)
1970
121.9 mm (4.8 in)
1971
61.1 mm (2.4 in)
1972
98.0 mm (3.9 in)
1973
77.9 mm (3.1 in)
1974
56.6 mm (2.2 in)
1975
60.9 mm (2.4 in)
1976
74.7 mm (2.9 in)
1977
63.5 mm (2.5 in)
1978
118.6 mm (4.7 in)
1979
91.7 mm (3.6 in)
1980
88.1 mm (3.5 in)
1981
106.7 mm (4.2 in)
1982
86.9 mm (3.4 in)
1983
72.1 mm (2.8 in)
1984
98.9 mm (3.9 in)
1985
82.3 mm (3.2 in)
1986
92.6 mm (3.6 in)
1987
7.6 mm (0.30 in)
Longest dry spell (CDD)
The longest dry spell of the year at Janesville, 1893 to 1987. The record is 45 days in 1893, marked on the chart; the median year is 23 days.
Longest dry spell (CDD) at Janesville by year
Year
Longest dry spell (CDD)
1893
45 days
1894
32 days
1895
22 days
1915
5 days
1916
7 days
1917
8 days
1944
27 days
1945
20 days
1946
22 days
1947
21 days
1948
23 days
1949
20 days
1950
30 days
1951
14 days
1952
30 days
1953
24 days
1954
19 days
1955
21 days
1956
17 days
1957
28 days
1958
31 days
1959
26 days
1960
17 days
1961
23 days
1962
17 days
1963
16 days
1964
24 days
1965
19 days
1966
26 days
1967
24 days
1968
19 days
1969
24 days
1970
20 days
1971
24 days
1972
19 days
1973
15 days
1974
25 days
1975
17 days
1976
26 days
1977
29 days
1978
26 days
1979
29 days
1980
16 days
1981
31 days
1982
24 days
1983
21 days
1984
18 days
1985
14 days
1986
23 days
1987
30 days
Each chart shows one value per year; the dot marks the record year. TXx is the hottest daily maximum, TNn the coldest daily minimum, Rx1day and Rx5day the largest one-day and five-day rain totals, and CDD the longest run of days with less than 1 mm of rain. A year with missing days can understate an extreme.
Frost Dates and Growing Season
38 years with a frost
Across 38 years with a frost, the median last spring frost at Janesville falls on 28 April and the median first autumn frost on 7 October, which leaves a median of 162 days between them.
Fitted over all years, the growing season changes by +2.0 days per decade at this station.
Frost dates and growing season at Janesville
Measure
Median, all years
Earliest period
Recent period (1951 to 1985)
Recent against earliest
Fitted trend
Last spring frost
28 April
n/a
27 April
n/a
-0.1 days per decade
First autumn frost
7 October
n/a
12 October
n/a
+1.8 days per decade
Growing days
162 days
n/a
163 days
n/a
+2.0 days per decade
A frost day is a day with a daily minimum at or below 0 C (32 F). The last spring frost and the first autumn frost are the last and first such days of the cold season, and growing days are the days between them. A negative trend for the last spring frost means it comes earlier.
Rainfall Return Levels
42 years, 1945 to 1986
A day with at least 54.4 mm (2.1 in) of rain is expected about once in 2 years. A day with at least 128.0 mm (5.0 in) of rain is expected about once in 100 years.
Rainfall return levels at Janesville: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
54.4 mm (2.1 in)
5 years
73.1 mm (2.9 in)
10 years
85.9 mm (3.4 in)
25 years
102.5 mm (4.0 in)
50 years
115.1 mm (4.5 in)
Longer than the 42 years of record
100 years
128.0 mm (5.0 in)
Longer than the 42 years of record
The levels come from a generalised extreme value (GEV) distribution fitted by L-moments to the wettest-day total of each year, 42 years of values from 1945 to 1986.
A return level is an estimate. It is least reliable for the long periods, 50 and 100 years, and for any period longer than the record behind the fit, where the fit has to reach past the largest day actually observed. It is not a forecast.
The largest wettest-day totals in the fit: 113.8 mm (4.5 in) in 1961; 102.1 mm (4.0 in) in 1952; 92.2 mm (3.6 in) in 1981.
Download the Data
Data for Janesville standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Janesville threshold days by year: CSV or JSON. Field meanings are on the data page.
Source: NOAA National Centers for Environmental Information, Global Historical Climatology Network Daily (GHCN-Daily). Records are computed by World Extreme Weather Monitor and are not official NOAA products. (US Government open data (NOAA NCEI)) Data as of 2026-10-14 (14 October 2026). Records are computed by this site and are not official.