Record envelope, standing records and threshold days for Joliet (USW00014834), Illinois, United States, with 134 years of record.
Key Facts for Joliet
Joliet (USW00014834) is a weather station in Illinois, United States at 41.55 latitude and -88.08 longitude, 168 m (551 ft) above sea level.
The station reports from 1893 to 2026, 134 years of record.
1,464 records set at Joliet still stand.
Records are tracked for tmax, tmin, prcp, snow: an element needs 30 years of data to be eligible.
Joliet set a daily record high minimum temperature of 25.2 C (77.4 F) on 30 June 2026.
About the Station
Location: Illinois, United States, 41.55 latitude, -88.08 longitude.
Elevation: 168 m (551 ft).
Period of record: 1893 to 2026, 134 years.
Eligible elements: tmax, tmin, prcp, snow.
Daily Record Envelope and 2026
16 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 Joliet. The lines show the 2026 daily maximum and minimum. 16 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.
Daily record high and record low at Joliet, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
19.4 C (66.9 F)
-28.9 C (-20.0 F)
16.3 C (61.3 F)
-21.1 C (-6.0 F)
Feb
20.6 C (69.1 F)
-28.9 C (-20.0 F)
20.2 C (68.4 F)
-16.5 C (2.3 F)
Mar
28.4 C (83.1 F)
-22.2 C (-8.0 F)
28.4 C (83.1 F)
-9.0 C (15.8 F)
Apr
32.2 C (90.0 F)
-10.0 C (14.0 F)
28.6 C (83.5 F)
-1.2 C (29.8 F)
May
35.0 C (95.0 F)
-3.3 C (26.1 F)
30.7 C (87.3 F)
-0.8 C (30.6 F)
Jun
38.9 C (102.0 F)
1.7 C (35.1 F)
34.2 C (93.6 F)
8.7 C (47.7 F)
Jul
39.4 C (102.9 F)
6.7 C (44.1 F)
26.1 C (79.0 F)
20.6 C (69.1 F)
Aug
38.3 C (100.9 F)
5.0 C (41.0 F)
n/a
n/a
Sep
38.3 C (100.9 F)
-2.2 C (28.0 F)
27.0 C (80.6 F)
9.7 C (49.5 F)
Oct
35.6 C (96.1 F)
-9.4 C (15.1 F)
27.5 C (81.5 F)
6.2 C (43.2 F)
Nov
27.2 C (81.0 F)
-23.3 C (-9.9 F)
n/a
n/a
Dec
20.6 C (69.1 F)
-28.9 C (-20.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Joliet still stand. 1895 holds the most, with 77.
Standing records at Joliet by the year they were set
Year set
Standing records
1893
15
1894
46
1895
77
1896
63
1897
62
1898
41
1899
52
1900
30
1927
1
1939
1
1946
42
1947
56
1948
29
1949
34
1950
57
1951
60
1952
39
1953
33
1954
41
1955
32
1956
25
1957
25
1958
30
1959
28
1960
32
1961
25
1962
35
1963
54
1964
35
1965
40
1966
26
1967
36
1968
28
1969
22
1970
28
1971
32
1972
32
1973
15
1974
31
2025
41
2026
33
All-Time Record Progression
1 new records
1 all-time records were set at Joliet between 11 June 1926 and 11 June 1926. Each dot is a new record.
When Joliet set new all-time records
Date
Kind
Detail
1926-06-11
Record daily precipitation
Record daily precipitation 174.2 mm (6.9 in)
Wettest Day of Each Month
Jun: 174.2 mm (6.9 in)
The wettest day on record for each calendar month at Joliet. The most was 174.2 mm (6.9 in) on 11 June 1926.
Record daily precipitation for each month at Joliet
Month
Record daily precipitation (mm)
Date
Jan
69.1 mm (2.7 in)
19 January 1907
Feb
59.4 mm (2.3 in)
6 February 1942
Mar
79.8 mm (3.1 in)
14 March 1944
Apr
88.9 mm (3.5 in)
5 April 1947
May
63.8 mm (2.5 in)
12 May 1966
Jun
174.2 mm (6.9 in)
11 June 1926
Jul
136.4 mm (5.4 in)
13 July 1957
Aug
83.3 mm (3.3 in)
17 August 1968
Sep
135.1 mm (5.3 in)
7 September 1942
Oct
86.4 mm (3.4 in)
11 October 1954
Nov
44.5 mm (1.8 in)
17 November 1928
Dec
75.9 mm (3.0 in)
19 December 1895
Period of Record Coverage
1893 to 2026
Complete yearUnder 90 percent of days
42 years of record at Joliet, 1893 to 2026. 7 years have data for under 90 percent of days and are left out of rankings: 1893, 1938, 1939, 1942, 1953, 1973, 2026.
Cooler than the station meanWarmer than the station mean
One stripe for each of 32 complete years at Joliet, 1894 to 2025. Blue stripes are years cooler than the station's own mean of 10.5 C (50.8 F); red stripes are warmer. The coolest year was 1950, at 8.3 C (47.0 F), and the warmest was 2025, at 11.9 C (53.5 F). The strongest colour marks a difference of 2.2 C (4.0 F).
Annual mean temperature at Joliet as warming stripes, 1894 to 2025
Year
Annual mean temperature
Difference from the station mean
1894
11.4 C
+0.96 C
1895
10.2 C
-0.29 C
1896
11.5 C
+1.05 C
1897
10.9 C
+0.46 C
1898
10.2 C
-0.27 C
1899
9.8 C
-0.71 C
1900
10.2 C
-0.31 C
1946
10.4 C
-0.03 C
1947
9.3 C
-1.15 C
1948
9.5 C
-1.02 C
1949
10.3 C
-0.17 C
1950
8.3 C
-2.13 C
1951
8.5 C
-1.97 C
1952
10.0 C
-0.51 C
1954
11.6 C
+1.13 C
1955
11.2 C
+0.76 C
1956
11.6 C
+1.16 C
1957
10.8 C
+0.29 C
1958
10.0 C
-0.45 C
1960
10.3 C
-0.22 C
1961
10.5 C
0.00 C
1962
9.9 C
-0.59 C
1963
10.1 C
-0.34 C
1964
11.5 C
+1.06 C
1965
11.1 C
+0.61 C
1966
10.6 C
+0.08 C
1967
10.1 C
-0.41 C
1968
11.1 C
+0.67 C
1969
10.2 C
-0.26 C
1970
10.8 C
+0.36 C
1971
11.3 C
+0.85 C
2025
11.9 C
+1.46 C
The fitted trend in annual mean temperature here over 1894 to 2025 is 0.04 C (-0.07 to 0.14) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: 0.1 F (-0.1 to 0.3) per decade. The slope is a straight line fitted to 32 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Joliet
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.04 C (-0.07 to 0.14) per decade
0.1 F (-0.1 to 0.3) per decade
1894 to 2025
32
Not clearly different from zero
Mean daily maximum
0.00 C (-0.12 to 0.11) per decade
-0.01 F (-0.22 to 0.20) per decade
1894 to 2025
32
Not clearly different from zero
Mean daily minimum
0.08 C (-0.03 to 0.20) per decade
0.1 F (-0.1 to 0.4) per decade
1894 to 2025
32
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
1893 to 2026
Yearly extremes at Joliet: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
39.4 C (102.9 F)
1897
36.1 C (97.0 F)
42
Coldest night (TNn)
-28.9 C (-20.0 F)
1897
-23.9 C (-11.0 F)
43
Wettest day (Rx1day)
174.2 mm (6.9 in)
1926
59.7 mm (2.4 in)
85
Wettest five days (Rx5day)
234.2 mm (9.2 in)
1926
85.2 mm (3.4 in)
84
Longest dry spell (CDD)
36 days
1917
20 days
85
Hottest day (TXx)
The hottest day of the year at Joliet, 1893 to 2026. The record is 39.4 C (102.9 F) in 1897, marked on the chart; the median year is 36.1 C (97.0 F).
Hottest day (TXx) at Joliet by year
Year
Hottest day (TXx)
1893
20.0 C (68.0 F)
1894
36.1 C (97.0 F)
1895
38.3 C (100.9 F)
1896
37.8 C (100.0 F)
1897
39.4 C (102.9 F)
1898
36.1 C (97.0 F)
1899
37.8 C (100.0 F)
1900
35.6 C (96.1 F)
1901
n/a
1902
n/a
1903
n/a
1904
n/a
1905
n/a
1906
n/a
1907
n/a
1908
n/a
1909
n/a
1910
n/a
1911
n/a
1912
n/a
1913
n/a
1914
n/a
1915
n/a
1916
n/a
1917
n/a
1918
n/a
1919
n/a
1920
n/a
1921
n/a
1922
n/a
1923
n/a
1924
n/a
1925
n/a
1926
n/a
1927
n/a
1928
n/a
1929
n/a
1930
n/a
1931
n/a
1932
n/a
1933
n/a
1934
n/a
1935
n/a
1936
n/a
1937
n/a
1938
18.3 C (64.9 F)
1939
28.9 C (84.0 F)
1940
n/a
1941
n/a
1942
22.2 C (72.0 F)
1943
n/a
1944
n/a
1945
n/a
1946
37.2 C (99.0 F)
1947
38.3 C (100.9 F)
1948
37.2 C (99.0 F)
1949
37.2 C (99.0 F)
1950
33.9 C (93.0 F)
1951
34.4 C (93.9 F)
1952
36.7 C (98.1 F)
1953
38.9 C (102.0 F)
1954
37.2 C (99.0 F)
1955
37.8 C (100.0 F)
1956
37.8 C (100.0 F)
1957
35.0 C (95.0 F)
1958
33.9 C (93.0 F)
1959
35.6 C (96.1 F)
1960
35.6 C (96.1 F)
1961
34.4 C (93.9 F)
1962
35.0 C (95.0 F)
1963
36.7 C (98.1 F)
1964
36.7 C (98.1 F)
1965
36.7 C (98.1 F)
1966
37.2 C (99.0 F)
1967
34.4 C (93.9 F)
1968
35.6 C (96.1 F)
1969
36.1 C (97.0 F)
1970
37.2 C (99.0 F)
1971
36.7 C (98.1 F)
1972
35.6 C (96.1 F)
1973
36.1 C (97.0 F)
1974
37.8 C (100.0 F)
2024
n/a
2025
35.0 C (95.0 F)
2026
34.2 C (93.6 F)
Coldest night (TNn)
The coldest night of the year at Joliet, 1893 to 2026. The record is -28.9 C (-20.0 F) in 1897, marked on the chart; the median year is -23.9 C (-11.0 F).
Coldest night (TNn) at Joliet by year
Year
Coldest night (TNn)
1893
-21.7 C (-7.1 F)
1894
-26.1 C (-15.0 F)
1895
-25.6 C (-14.1 F)
1896
-23.3 C (-9.9 F)
1897
-28.9 C (-20.0 F)
1898
-22.2 C (-8.0 F)
1899
-28.9 C (-20.0 F)
1900
-21.7 C (-7.1 F)
1901
n/a
1902
n/a
1903
n/a
1904
n/a
1905
n/a
1906
n/a
1907
n/a
1908
n/a
1909
n/a
1910
n/a
1911
n/a
1912
n/a
1913
n/a
1914
n/a
1915
n/a
1916
n/a
1917
n/a
1918
n/a
1919
n/a
1920
n/a
1921
n/a
1922
n/a
1923
n/a
1924
n/a
1925
n/a
1926
n/a
1927
0.6 C (33.1 F)
1928
n/a
1929
n/a
1930
n/a
1931
n/a
1932
n/a
1933
n/a
1934
n/a
1935
n/a
1936
n/a
1937
n/a
1938
1.7 C (35.1 F)
1939
21.1 C (70.0 F)
1940
n/a
1941
n/a
1942
7.8 C (46.0 F)
1943
n/a
1944
n/a
1945
n/a
1946
-20.6 C (-5.1 F)
1947
-23.3 C (-9.9 F)
1948
-22.8 C (-9.0 F)
1949
-23.3 C (-9.9 F)
1950
-28.3 C (-18.9 F)
1951
-28.9 C (-20.0 F)
1952
-20.0 C (-4.0 F)
1953
-23.9 C (-11.0 F)
1954
-22.2 C (-8.0 F)
1955
-23.9 C (-11.0 F)
1956
-17.2 C (1.0 F)
1957
-23.9 C (-11.0 F)
1958
-25.0 C (-13.0 F)
1959
-24.4 C (-11.9 F)
1960
-27.8 C (-18.0 F)
1961
-21.7 C (-7.1 F)
1962
-26.1 C (-15.0 F)
1963
-28.3 C (-18.9 F)
1964
-21.1 C (-6.0 F)
1965
-24.4 C (-11.9 F)
1966
-27.2 C (-17.0 F)
1967
-23.9 C (-11.0 F)
1968
-25.6 C (-14.1 F)
1969
-24.4 C (-11.9 F)
1970
-27.2 C (-17.0 F)
1971
-22.8 C (-9.0 F)
1972
-25.6 C (-14.1 F)
1973
-18.3 C (-0.9 F)
1974
-25.6 C (-14.1 F)
2024
n/a
2025
-21.0 C (-5.8 F)
2026
-21.1 C (-6.0 F)
Wettest day (Rx1day)
The wettest day of the year at Joliet, 1893 to 2026. The record is 174.2 mm (6.9 in) in 1926, marked on the chart; the median year is 59.7 mm (2.4 in).
Wettest day (Rx1day) at Joliet by year
Year
Wettest day (Rx1day)
1893
18.0 mm (0.7 in)
1894
39.4 mm (1.6 in)
1895
75.9 mm (3.0 in)
1896
45.7 mm (1.8 in)
1897
61.0 mm (2.4 in)
1898
62.0 mm (2.4 in)
1899
50.3 mm (2.0 in)
1900
59.2 mm (2.3 in)
1901
39.6 mm (1.6 in)
1902
76.2 mm (3.0 in)
1903
42.4 mm (1.7 in)
1904
49.5 mm (1.9 in)
1905
54.6 mm (2.1 in)
1906
63.2 mm (2.5 in)
1907
69.1 mm (2.7 in)
1908
57.2 mm (2.3 in)
1909
38.6 mm (1.5 in)
1910
32.5 mm (1.3 in)
1911
106.7 mm (4.2 in)
1912
39.4 mm (1.6 in)
1913
52.6 mm (2.1 in)
1914
66.5 mm (2.6 in)
1915
62.5 mm (2.5 in)
1916
54.4 mm (2.1 in)
1917
45.2 mm (1.8 in)
1918
48.3 mm (1.9 in)
1919
66.0 mm (2.6 in)
1920
53.1 mm (2.1 in)
1921
42.2 mm (1.7 in)
1922
54.1 mm (2.1 in)
1923
61.0 mm (2.4 in)
1924
39.6 mm (1.6 in)
1925
36.8 mm (1.4 in)
1926
174.2 mm (6.9 in)
1927
68.6 mm (2.7 in)
1928
54.6 mm (2.1 in)
1929
70.6 mm (2.8 in)
1930
72.1 mm (2.8 in)
1931
55.1 mm (2.2 in)
1932
60.5 mm (2.4 in)
1933
70.6 mm (2.8 in)
1934
40.4 mm (1.6 in)
1935
39.6 mm (1.6 in)
1936
59.7 mm (2.4 in)
1937
29.2 mm (1.1 in)
1938
45.2 mm (1.8 in)
1939
62.2 mm (2.4 in)
1940
39.4 mm (1.6 in)
1941
85.9 mm (3.4 in)
1942
135.1 mm (5.3 in)
1943
47.8 mm (1.9 in)
1944
79.8 mm (3.1 in)
1945
53.6 mm (2.1 in)
1946
81.3 mm (3.2 in)
1947
88.9 mm (3.5 in)
1948
66.0 mm (2.6 in)
1949
57.7 mm (2.3 in)
1950
64.3 mm (2.5 in)
1951
89.9 mm (3.5 in)
1952
66.0 mm (2.6 in)
1953
39.6 mm (1.6 in)
1954
86.4 mm (3.4 in)
1955
65.3 mm (2.6 in)
1956
46.0 mm (1.8 in)
1957
136.4 mm (5.4 in)
1958
79.2 mm (3.1 in)
1959
51.6 mm (2.0 in)
1960
62.7 mm (2.5 in)
1961
84.8 mm (3.3 in)
1962
64.3 mm (2.5 in)
1963
47.8 mm (1.9 in)
1964
61.5 mm (2.4 in)
1965
72.9 mm (2.9 in)
1966
73.7 mm (2.9 in)
1967
67.3 mm (2.6 in)
1968
83.3 mm (3.3 in)
1969
61.5 mm (2.4 in)
1970
85.6 mm (3.4 in)
1971
53.3 mm (2.1 in)
1972
66.0 mm (2.6 in)
1973
58.9 mm (2.3 in)
1974
36.8 mm (1.4 in)
2024
0.0 mm (0.00 in)
2025
32.0 mm (1.3 in)
2026
31.0 mm (1.2 in)
Wettest five days (Rx5day)
The wettest five days of the year at Joliet, 1893 to 2026. The record is 234.2 mm (9.2 in) in 1926, marked on the chart; the median year is 85.2 mm (3.4 in).
Wettest five days (Rx5day) at Joliet by year
Year
Wettest five days (Rx5day)
1893
32.5 mm (1.3 in)
1894
98.5 mm (3.9 in)
1895
143.8 mm (5.7 in)
1896
78.7 mm (3.1 in)
1897
108.8 mm (4.3 in)
1898
118.8 mm (4.7 in)
1899
81.0 mm (3.2 in)
1900
91.4 mm (3.6 in)
1901
69.9 mm (2.8 in)
1902
134.9 mm (5.3 in)
1903
81.0 mm (3.2 in)
1904
72.3 mm (2.8 in)
1905
70.3 mm (2.8 in)
1906
74.7 mm (2.9 in)
1907
90.4 mm (3.6 in)
1908
78.7 mm (3.1 in)
1909
65.6 mm (2.6 in)
1910
51.5 mm (2.0 in)
1911
232.0 mm (9.1 in)
1912
59.3 mm (2.3 in)
1913
58.2 mm (2.3 in)
1914
86.8 mm (3.4 in)
1915
89.7 mm (3.5 in)
1916
71.0 mm (2.8 in)
1917
74.9 mm (2.9 in)
1918
74.5 mm (2.9 in)
1919
118.3 mm (4.7 in)
1920
72.6 mm (2.9 in)
1921
71.7 mm (2.8 in)
1922
68.3 mm (2.7 in)
1923
115.4 mm (4.5 in)
1924
99.3 mm (3.9 in)
1925
72.1 mm (2.8 in)
1926
234.2 mm (9.2 in)
1927
125.9 mm (5.0 in)
1928
72.0 mm (2.8 in)
1929
104.6 mm (4.1 in)
1930
74.7 mm (2.9 in)
1931
99.3 mm (3.9 in)
1932
82.3 mm (3.2 in)
1933
91.2 mm (3.6 in)
1934
71.3 mm (2.8 in)
1935
72.5 mm (2.9 in)
1936
163.3 mm (6.4 in)
1937
49.5 mm (1.9 in)
1938
73.7 mm (2.9 in)
1939
96.0 mm (3.8 in)
1940
63.0 mm (2.5 in)
1941
195.4 mm (7.7 in)
1942
180.5 mm (7.1 in)
1943
83.6 mm (3.3 in)
1944
96.2 mm (3.8 in)
1945
95.3 mm (3.8 in)
1946
88.4 mm (3.5 in)
1947
136.1 mm (5.4 in)
1948
77.5 mm (3.1 in)
1949
82.0 mm (3.2 in)
1950
119.9 mm (4.7 in)
1951
98.8 mm (3.9 in)
1952
118.7 mm (4.7 in)
1953
68.3 mm (2.7 in)
1954
115.6 mm (4.6 in)
1955
93.0 mm (3.7 in)
1956
99.4 mm (3.9 in)
1957
161.8 mm (6.4 in)
1958
89.6 mm (3.5 in)
1959
80.8 mm (3.2 in)
1960
65.7 mm (2.6 in)
1961
157.0 mm (6.2 in)
1962
70.6 mm (2.8 in)
1963
82.1 mm (3.2 in)
1964
67.1 mm (2.6 in)
1965
98.3 mm (3.9 in)
1966
117.9 mm (4.6 in)
1967
123.4 mm (4.9 in)
1968
90.0 mm (3.5 in)
1969
69.6 mm (2.7 in)
1970
105.8 mm (4.2 in)
1971
65.8 mm (2.6 in)
1972
102.6 mm (4.0 in)
1973
88.6 mm (3.5 in)
1974
59.5 mm (2.3 in)
2024
n/a
2025
27.0 mm (1.1 in)
2026
35.1 mm (1.4 in)
Longest dry spell (CDD)
The longest dry spell of the year at Joliet, 1893 to 2026. The record is 36 days in 1917, marked on the chart; the median year is 20 days.
Longest dry spell (CDD) at Joliet by year
Year
Longest dry spell (CDD)
1893
11 days
1894
18 days
1895
25 days
1896
17 days
1897
24 days
1898
23 days
1899
26 days
1900
17 days
1901
18 days
1902
22 days
1903
14 days
1904
22 days
1905
18 days
1906
20 days
1907
17 days
1908
35 days
1909
17 days
1910
21 days
1911
13 days
1912
29 days
1913
16 days
1914
23 days
1915
33 days
1916
23 days
1917
36 days
1918
16 days
1919
27 days
1920
23 days
1921
14 days
1922
16 days
1923
18 days
1924
14 days
1925
23 days
1926
11 days
1927
16 days
1928
20 days
1929
19 days
1930
22 days
1931
19 days
1932
16 days
1933
33 days
1934
26 days
1935
15 days
1936
27 days
1937
19 days
1938
23 days
1939
29 days
1940
17 days
1941
14 days
1942
27 days
1943
28 days
1944
28 days
1945
20 days
1946
22 days
1947
26 days
1948
29 days
1949
21 days
1950
26 days
1951
16 days
1952
33 days
1953
22 days
1954
20 days
1955
15 days
1956
25 days
1957
23 days
1958
27 days
1959
22 days
1960
14 days
1961
18 days
1962
18 days
1963
18 days
1964
24 days
1965
20 days
1966
23 days
1967
19 days
1968
20 days
1969
25 days
1970
15 days
1971
24 days
1972
14 days
1973
14 days
1974
15 days
2024
3 days
2025
16 days
2026
12 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
32 years with a frost
Across 32 years with a frost, the median last spring frost at Joliet falls on 25 April and the median first autumn frost on 20 October, which leaves a median of 177 days between them.
Fitted over all years, the growing season changes by +0.8 days per decade at this station.
Frost dates and growing season at Joliet
Measure
Median, all years
Earliest period
Recent period (1896 to 2025)
Recent against earliest
Fitted trend
Last spring frost
25 April
n/a
25 April
n/a
+0.3 days per decade
First autumn frost
20 October
n/a
22 October
n/a
+1.1 days per decade
Growing days
177 days
n/a
177 days
n/a
+0.8 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
74 years, 1896 to 1973
A day with at least 58.4 mm (2.3 in) of rain is expected about once in 2 years. A day with at least 145.3 mm (5.7 in) of rain is expected about once in 100 years.
Rainfall return levels at Joliet: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
58.4 mm (2.3 in)
5 years
77.4 mm (3.0 in)
10 years
91.5 mm (3.6 in)
25 years
111.3 mm (4.4 in)
50 years
127.6 mm (5.0 in)
100 years
145.3 mm (5.7 in)
Longer than the 74 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, 74 years of values from 1896 to 1973.
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: 174.2 mm (6.9 in) in 1926; 136.4 mm (5.4 in) in 1957; 135.1 mm (5.3 in) in 1942.
Download the Data
Data for Joliet standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Joliet 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 2026-10-15 (15 October 2026). Records are computed by this site and are not official.