Record envelope, standing records and threshold days for Grand River Lock (USC00473214), Wisconsin, United States, with 59 years of record.
Key Facts for Grand River Lock
Grand River Lock (USC00473214) is a weather station in Wisconsin, United States at 43.77 latitude and -89.30 longitude, 235 m (771 ft) above sea level.
The station reports from 1896 to 1954, 59 years of record.
1,464 records set at Grand River Lock still stand.
Records are tracked for tmax, tmin, prcp, snow: an element needs 30 years of data to be eligible.
Grand River Lock tied a daily record low minimum temperature of 4.4 C (39.9 F) on 11 August 1954.
About the Station
Location: Wisconsin, United States, 43.77 latitude, -89.30 longitude.
Elevation: 235 m (771 ft).
Period of record: 1896 to 1954, 59 years.
Eligible elements: tmax, tmin, prcp, snow.
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 Grand River Lock. 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 Grand River Lock, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
13.3 C (55.9 F)
-42.8 C (-45.0 F)
n/a
n/a
Feb
18.3 C (64.9 F)
-41.1 C (-42.0 F)
n/a
n/a
Mar
27.8 C (82.0 F)
-32.2 C (-26.0 F)
n/a
n/a
Apr
31.7 C (89.1 F)
-13.9 C (7.0 F)
n/a
n/a
May
37.8 C (100.0 F)
-5.6 C (21.9 F)
n/a
n/a
Jun
38.3 C (100.9 F)
-1.1 C (30.0 F)
n/a
n/a
Jul
40.6 C (105.1 F)
2.8 C (37.0 F)
n/a
n/a
Aug
37.8 C (100.0 F)
-2.8 C (27.0 F)
n/a
n/a
Sep
38.3 C (100.9 F)
-6.7 C (19.9 F)
n/a
n/a
Oct
30.0 C (86.0 F)
-16.7 C (1.9 F)
n/a
n/a
Nov
25.6 C (78.1 F)
-25.0 C (-13.0 F)
n/a
n/a
Dec
15.6 C (60.1 F)
-32.2 C (-26.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Grand River Lock still stand. 1936 holds the most, with 63.
Standing records at Grand River Lock by the year they were set
Year set
Standing records
1908
26
1909
34
1910
36
1911
37
1912
36
1913
38
1914
34
1915
28
1916
43
1917
37
1918
36
1919
20
1920
39
1921
38
1922
30
1923
33
1924
35
1925
43
1926
28
1927
31
1928
33
1929
31
1930
52
1931
52
1932
27
1933
35
1934
47
1935
23
1936
63
1937
31
1938
17
1939
16
1940
22
1941
14
1942
23
1943
22
1944
25
1945
22
1946
20
1947
32
1948
20
1949
18
1950
30
1951
43
1952
24
1953
24
1954
16
All-Time Record Progression
3 new records
3 all-time records were set at Grand River Lock between 30 June 1938 and 30 January 1951. Each dot is a new record.
When Grand River Lock set new all-time records
Date
Kind
Detail
1938-06-30
Record daily precipitation
Record daily precipitation 101.1 mm (4.0 in)
1940-06-22
Record daily precipitation
Record daily precipitation 135.9 mm (5.4 in)
1951-01-30
Record low minimum temperature
Record low minimum temperature -42.8 C (-45.0 F)
Wettest Day of Each Month
Jun: 135.9 mm (5.4 in)
The wettest day on record for each calendar month at Grand River Lock. The most was 135.9 mm (5.4 in) on 22 June 1940.
Record daily precipitation for each month at Grand River Lock
Month
Record daily precipitation (mm)
Date
Jan
35.6 mm (1.4 in)
5 January 1939
Feb
50.8 mm (2.0 in)
23 February 1922
Mar
49.5 mm (1.9 in)
4 March 1924
Apr
42.7 mm (1.7 in)
10 April 1953
May
91.4 mm (3.6 in)
13 May 1896
Jun
135.9 mm (5.4 in)
22 June 1940
Jul
75.2 mm (3.0 in)
20 July 1912
Aug
90.4 mm (3.6 in)
17 August 1906
Sep
87.9 mm (3.5 in)
14 September 1931
Oct
68.6 mm (2.7 in)
20 October 1937
Nov
41.7 mm (1.6 in)
26 November 1906
Dec
36.8 mm (1.4 in)
2 December 1921
Period of Record Coverage
1908 to 1954
Complete yearUnder 90 percent of days
47 years of record at Grand River Lock, 1908 to 1954. 3 years have data for under 90 percent of days and are left out of rankings: 1908, 1911, 1954.
Cooler than the station meanWarmer than the station mean
One stripe for each of 44 complete years at Grand River Lock, 1909 to 1953. Blue stripes are years cooler than the station's own mean of 7.6 C (45.6 F); red stripes are warmer. The coolest year was 1917, at 5.3 C (41.6 F), and the warmest was 1931, at 10.5 C (50.8 F). The strongest colour marks a difference of 2.9 C (5.2 F).
Annual mean temperature at Grand River Lock as warming stripes, 1909 to 1953
Year
Annual mean temperature
Difference from the station mean
1909
7.0 C
-0.55 C
1910
7.2 C
-0.37 C
1911
8.3 C
+0.72 C
1912
6.3 C
-1.28 C
1913
8.1 C
+0.55 C
1914
7.9 C
+0.29 C
1915
7.5 C
-0.07 C
1916
6.9 C
-0.68 C
1917
5.3 C
-2.24 C
1918
7.3 C
-0.29 C
1919
7.6 C
+0.06 C
1920
7.1 C
-0.51 C
1921
9.3 C
+1.75 C
1922
7.9 C
+0.36 C
1923
7.4 C
-0.15 C
1924
6.1 C
-1.49 C
1925
7.4 C
-0.15 C
1926
6.9 C
-0.69 C
1927
7.9 C
+0.31 C
1928
8.3 C
+0.68 C
1929
6.6 C
-0.99 C
1930
8.4 C
+0.82 C
1931
10.5 C
+2.89 C
1932
7.5 C
-0.10 C
1933
8.2 C
+0.65 C
1934
8.4 C
+0.82 C
1935
7.3 C
-0.27 C
1936
6.9 C
-0.63 C
1937
7.2 C
-0.42 C
1938
8.7 C
+1.16 C
1939
8.5 C
+0.93 C
1940
6.9 C
-0.67 C
1941
8.6 C
+1.07 C
1942
7.8 C
+0.18 C
1943
7.0 C
-0.54 C
1944
8.4 C
+0.85 C
1945
7.0 C
-0.57 C
1946
8.4 C
+0.86 C
1947
7.5 C
-0.10 C
1948
7.6 C
+0.03 C
1950
6.0 C
-1.58 C
1951
5.9 C
-1.65 C
1952
7.6 C
+0.02 C
1953
8.4 C
+0.84 C
The fitted trend in annual mean temperature here over 1909 to 1953 is 0.1 C (-0.2 to 0.3) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: 0.1 F (-0.3 to 0.5) per decade. The slope is a straight line fitted to 44 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Grand River Lock
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.1 C (-0.2 to 0.3) per decade
0.1 F (-0.3 to 0.5) per decade
1909 to 1953
44
Not clearly different from zero
Mean daily maximum
0.1 C (-0.1 to 0.4) per decade
0.2 F (-0.2 to 0.7) per decade
1909 to 1953
44
Not clearly different from zero
Mean daily minimum
-0.01 C (-0.24 to 0.23) per decade
-0.01 F (-0.43 to 0.41) per decade
1909 to 1953
44
Not clearly different from zero
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
1896 to 1954
Yearly extremes at Grand River Lock: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
40.6 C (105.1 F)
1936
35.6 C (96.1 F)
47
Coldest night (TNn)
-42.8 C (-45.0 F)
1951
-31.1 C (-24.0 F)
47
Wettest day (Rx1day)
135.9 mm (5.4 in)
1940
49.5 mm (1.9 in)
59
Wettest five days (Rx5day)
182.9 mm (7.2 in)
1940
81.1 mm (3.2 in)
59
Longest dry spell (CDD)
38 days
1942
22 days
59
Hottest day (TXx)
The hottest day of the year at Grand River Lock, 1896 to 1954. The record is 40.6 C (105.1 F) in 1936, marked on the chart; the median year is 35.6 C (96.1 F).
Hottest day (TXx) at Grand River Lock by year
Year
Hottest day (TXx)
1896
n/a
1897
n/a
1898
n/a
1899
n/a
1900
n/a
1901
n/a
1902
n/a
1903
n/a
1904
n/a
1905
n/a
1906
n/a
1907
n/a
1908
35.6 C (96.1 F)
1909
36.7 C (98.1 F)
1910
36.7 C (98.1 F)
1911
36.1 C (97.0 F)
1912
35.0 C (95.0 F)
1913
37.2 C (99.0 F)
1914
36.7 C (98.1 F)
1915
32.2 C (90.0 F)
1916
39.4 C (102.9 F)
1917
35.6 C (96.1 F)
1918
36.7 C (98.1 F)
1919
35.0 C (95.0 F)
1920
33.3 C (91.9 F)
1921
40.0 C (104.0 F)
1922
38.3 C (100.9 F)
1923
36.7 C (98.1 F)
1924
32.8 C (91.0 F)
1925
35.0 C (95.0 F)
1926
36.1 C (97.0 F)
1927
33.9 C (93.0 F)
1928
33.9 C (93.0 F)
1929
33.9 C (93.0 F)
1930
37.8 C (100.0 F)
1931
38.9 C (102.0 F)
1932
35.0 C (95.0 F)
1933
36.1 C (97.0 F)
1934
40.0 C (104.0 F)
1935
33.9 C (93.0 F)
1936
40.6 C (105.1 F)
1937
37.2 C (99.0 F)
1938
33.9 C (93.0 F)
1939
36.1 C (97.0 F)
1940
35.6 C (96.1 F)
1941
37.2 C (99.0 F)
1942
34.4 C (93.9 F)
1943
33.9 C (93.0 F)
1944
35.6 C (96.1 F)
1945
35.0 C (95.0 F)
1946
34.4 C (93.9 F)
1947
36.7 C (98.1 F)
1948
37.8 C (100.0 F)
1949
35.0 C (95.0 F)
1950
31.7 C (89.1 F)
1951
31.7 C (89.1 F)
1952
33.3 C (91.9 F)
1953
35.0 C (95.0 F)
1954
33.9 C (93.0 F)
Coldest night (TNn)
The coldest night of the year at Grand River Lock, 1896 to 1954. The record is -42.8 C (-45.0 F) in 1951, marked on the chart; the median year is -31.1 C (-24.0 F).
Coldest night (TNn) at Grand River Lock by year
Year
Coldest night (TNn)
1896
n/a
1897
n/a
1898
n/a
1899
n/a
1900
n/a
1901
n/a
1902
n/a
1903
n/a
1904
n/a
1905
n/a
1906
n/a
1907
n/a
1908
-23.3 C (-9.9 F)
1909
-27.2 C (-17.0 F)
1910
-35.0 C (-31.0 F)
1911
-35.6 C (-32.1 F)
1912
-36.7 C (-34.1 F)
1913
-28.3 C (-18.9 F)
1914
-31.1 C (-24.0 F)
1915
-32.8 C (-27.0 F)
1916
-32.8 C (-27.0 F)
1917
-35.6 C (-32.1 F)
1918
-40.0 C (-40.0 F)
1919
-35.6 C (-32.1 F)
1920
-31.1 C (-24.0 F)
1921
-28.9 C (-20.0 F)
1922
-33.9 C (-29.0 F)
1923
-28.9 C (-20.0 F)
1924
-32.8 C (-27.0 F)
1925
-28.3 C (-18.9 F)
1926
-30.0 C (-22.0 F)
1927
-31.7 C (-25.1 F)
1928
-35.6 C (-32.1 F)
1929
-41.1 C (-42.0 F)
1930
-37.2 C (-35.0 F)
1931
-28.3 C (-18.9 F)
1932
-32.2 C (-26.0 F)
1933
-32.8 C (-27.0 F)
1934
-26.1 C (-15.0 F)
1935
-32.2 C (-26.0 F)
1936
-37.2 C (-35.0 F)
1937
-28.3 C (-18.9 F)
1938
-28.9 C (-20.0 F)
1939
-22.8 C (-9.0 F)
1940
-30.0 C (-22.0 F)
1941
-26.1 C (-15.0 F)
1942
-33.9 C (-29.0 F)
1943
-35.0 C (-31.0 F)
1944
-26.7 C (-16.1 F)
1945
-27.8 C (-18.0 F)
1946
-27.8 C (-18.0 F)
1947
-29.4 C (-20.9 F)
1948
-31.1 C (-24.0 F)
1949
-30.0 C (-22.0 F)
1950
-32.2 C (-26.0 F)
1951
-42.8 C (-45.0 F)
1952
-29.4 C (-20.9 F)
1953
-24.4 C (-11.9 F)
1954
-28.3 C (-18.9 F)
Wettest day (Rx1day)
The wettest day of the year at Grand River Lock, 1896 to 1954. The record is 135.9 mm (5.4 in) in 1940, marked on the chart; the median year is 49.5 mm (1.9 in).
Wettest day (Rx1day) at Grand River Lock by year
Year
Wettest day (Rx1day)
1896
91.4 mm (3.6 in)
1897
47.8 mm (1.9 in)
1898
44.2 mm (1.7 in)
1899
44.7 mm (1.8 in)
1900
59.7 mm (2.4 in)
1901
63.0 mm (2.5 in)
1902
51.8 mm (2.0 in)
1903
68.1 mm (2.7 in)
1904
56.6 mm (2.2 in)
1905
77.7 mm (3.1 in)
1906
90.4 mm (3.6 in)
1907
57.2 mm (2.3 in)
1908
43.2 mm (1.7 in)
1909
40.6 mm (1.6 in)
1910
40.1 mm (1.6 in)
1911
37.1 mm (1.5 in)
1912
75.2 mm (3.0 in)
1913
38.1 mm (1.5 in)
1914
53.8 mm (2.1 in)
1915
57.2 mm (2.3 in)
1916
38.1 mm (1.5 in)
1917
61.0 mm (2.4 in)
1918
48.3 mm (1.9 in)
1919
38.6 mm (1.5 in)
1920
62.2 mm (2.4 in)
1921
45.0 mm (1.8 in)
1922
50.8 mm (2.0 in)
1923
40.6 mm (1.6 in)
1924
49.5 mm (1.9 in)
1925
61.0 mm (2.4 in)
1926
63.5 mm (2.5 in)
1927
49.5 mm (1.9 in)
1928
38.1 mm (1.5 in)
1929
49.5 mm (1.9 in)
1930
47.0 mm (1.9 in)
1931
87.9 mm (3.5 in)
1932
44.5 mm (1.8 in)
1933
41.9 mm (1.6 in)
1934
31.8 mm (1.3 in)
1935
72.4 mm (2.9 in)
1936
48.3 mm (1.9 in)
1937
82.6 mm (3.3 in)
1938
101.1 mm (4.0 in)
1939
39.4 mm (1.6 in)
1940
135.9 mm (5.4 in)
1941
45.0 mm (1.8 in)
1942
64.8 mm (2.6 in)
1943
31.8 mm (1.3 in)
1944
38.1 mm (1.5 in)
1945
41.9 mm (1.6 in)
1946
58.4 mm (2.3 in)
1947
65.3 mm (2.6 in)
1948
28.4 mm (1.1 in)
1949
35.6 mm (1.4 in)
1950
68.6 mm (2.7 in)
1951
35.6 mm (1.4 in)
1952
36.3 mm (1.4 in)
1953
61.0 mm (2.4 in)
1954
43.2 mm (1.7 in)
Wettest five days (Rx5day)
The wettest five days of the year at Grand River Lock, 1896 to 1954. The record is 182.9 mm (7.2 in) in 1940, marked on the chart; the median year is 81.1 mm (3.2 in).
Wettest five days (Rx5day) at Grand River Lock by year
Year
Wettest five days (Rx5day)
1896
124.0 mm (4.9 in)
1897
85.9 mm (3.4 in)
1898
70.0 mm (2.8 in)
1899
77.5 mm (3.1 in)
1900
89.2 mm (3.5 in)
1901
81.1 mm (3.2 in)
1902
102.2 mm (4.0 in)
1903
96.0 mm (3.8 in)
1904
98.0 mm (3.9 in)
1905
108.4 mm (4.3 in)
1906
102.1 mm (4.0 in)
1907
93.0 mm (3.7 in)
1908
62.0 mm (2.4 in)
1909
64.5 mm (2.5 in)
1910
53.0 mm (2.1 in)
1911
87.8 mm (3.5 in)
1912
105.9 mm (4.2 in)
1913
69.9 mm (2.8 in)
1914
92.1 mm (3.6 in)
1915
116.7 mm (4.6 in)
1916
63.0 mm (2.5 in)
1917
69.9 mm (2.8 in)
1918
89.0 mm (3.5 in)
1919
68.8 mm (2.7 in)
1920
95.4 mm (3.8 in)
1921
66.4 mm (2.6 in)
1922
67.4 mm (2.7 in)
1923
47.0 mm (1.9 in)
1924
91.9 mm (3.6 in)
1925
76.2 mm (3.0 in)
1926
72.4 mm (2.9 in)
1927
68.5 mm (2.7 in)
1928
78.8 mm (3.1 in)
1929
87.6 mm (3.4 in)
1930
68.5 mm (2.7 in)
1931
119.1 mm (4.7 in)
1932
69.9 mm (2.8 in)
1933
76.2 mm (3.0 in)
1934
62.8 mm (2.5 in)
1935
94.0 mm (3.7 in)
1936
63.5 mm (2.5 in)
1937
83.9 mm (3.3 in)
1938
162.1 mm (6.4 in)
1939
49.5 mm (1.9 in)
1940
182.9 mm (7.2 in)
1941
71.7 mm (2.8 in)
1942
111.8 mm (4.4 in)
1943
85.1 mm (3.4 in)
1944
81.3 mm (3.2 in)
1945
76.7 mm (3.0 in)
1946
85.3 mm (3.4 in)
1947
65.3 mm (2.6 in)
1948
50.8 mm (2.0 in)
1949
67.1 mm (2.6 in)
1950
94.0 mm (3.7 in)
1951
53.8 mm (2.1 in)
1952
45.5 mm (1.8 in)
1953
144.1 mm (5.7 in)
1954
83.4 mm (3.3 in)
Longest dry spell (CDD)
The longest dry spell of the year at Grand River Lock, 1896 to 1954. The record is 38 days in 1942, marked on the chart; the median year is 22 days.
Longest dry spell (CDD) at Grand River Lock by year
Year
Longest dry spell (CDD)
1896
15 days
1897
24 days
1898
15 days
1899
25 days
1900
18 days
1901
15 days
1902
23 days
1903
26 days
1904
20 days
1905
17 days
1906
19 days
1907
17 days
1908
26 days
1909
20 days
1910
37 days
1911
26 days
1912
20 days
1913
21 days
1914
13 days
1915
14 days
1916
22 days
1917
21 days
1918
22 days
1919
36 days
1920
21 days
1921
17 days
1922
26 days
1923
17 days
1924
26 days
1925
28 days
1926
21 days
1927
34 days
1928
17 days
1929
22 days
1930
29 days
1931
23 days
1932
23 days
1933
27 days
1934
24 days
1935
18 days
1936
23 days
1937
21 days
1938
15 days
1939
23 days
1940
18 days
1941
22 days
1942
38 days
1943
25 days
1944
25 days
1945
16 days
1946
17 days
1947
31 days
1948
30 days
1949
34 days
1950
30 days
1951
14 days
1952
30 days
1953
30 days
1954
23 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
44 years with a frost
Across 44 years with a frost, the median last spring frost at Grand River Lock falls on 9 May and the median first autumn frost on 26 September, which leaves a median of 139 days between them.
Fitted over all years, the growing season changes by -1.2 days per decade at this station.
Frost dates and growing season at Grand River Lock
Measure
Median, all years
Earliest period
Recent period (1923 to 1953)
Recent against earliest
Fitted trend
Last spring frost
9 May
n/a
9 May
n/a
+0.6 days per decade
First autumn frost
26 September
n/a
26 September
n/a
-0.6 days per decade
Growing days
139 days
n/a
139 days
n/a
-1.2 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
47 years, 1896 to 1953
A day with at least 47.1 mm (1.9 in) of rain is expected about once in 2 years. A day with at least 140.6 mm (5.5 in) of rain is expected about once in 100 years.
Rainfall return levels at Grand River Lock: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
47.1 mm (1.9 in)
5 years
63.1 mm (2.5 in)
10 years
76.5 mm (3.0 in)
25 years
97.8 mm (3.9 in)
50 years
117.4 mm (4.6 in)
Longer than the 47 years of record
100 years
140.6 mm (5.5 in)
Longer than the 47 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, 47 years of values from 1896 to 1953.
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: 135.9 mm (5.4 in) in 1940; 101.1 mm (4.0 in) in 1938; 91.4 mm (3.6 in) in 1896.
Station Changes
1 suspected
One change was suspected in the annual mean temperature of Grand River Lock, at 1932. Each is measured against neighbouring stations.
Relative to 5 neighbouring stations, the station's annual mean temperature from 1932 ran 0.2 C (0.3 F) lower than in the years before (possible change).
Suspected changes in the annual mean temperature at Grand River Lock, against neighbouring stations
Year
Shift (C)
Shift (F)
Strength
Neighbours
1932
-0.2
-0.3
possible
5
Possible change at the station (a move, a new instrument or a new site); the record is kept as measured. A "likely" change has a larger test statistic than a "possible" one. Neither says why the station differs from its neighbours. How changes are found, and the largest ones.
Download the Data
Data for Grand River Lock standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Grand River Lock 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.