Record envelope, standing records and threshold days for Williamstown (USC00158714), Kentucky, United States, with 115 years of record.
Key Facts for Williamstown
Williamstown (USC00158714) is a weather station in Kentucky, United States at 38.64 latitude and -84.56 longitude, 295 m (969 ft) above sea level.
The station reports from 1902 to 2016, 115 years of record.
1,464 records set at Williamstown still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Williamstown set a daily record precipitation of 47.8 mm (1.9 in) on 20 August 2015.
About the Station
Location: Kentucky, United States, 38.64 latitude, -84.56 longitude.
Elevation: 295 m (969 ft).
Period of record: 1902 to 2016, 115 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 Williamstown. 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 Williamstown, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
24.4 C (75.9 F)
-30.6 C (-23.1 F)
n/a
n/a
Feb
25.0 C (77.0 F)
-25.6 C (-14.1 F)
n/a
n/a
Mar
30.6 C (87.1 F)
-18.9 C (-2.0 F)
n/a
n/a
Apr
34.4 C (93.9 F)
-10.0 C (14.0 F)
n/a
n/a
May
37.2 C (99.0 F)
-2.8 C (27.0 F)
n/a
n/a
Jun
41.7 C (107.1 F)
2.8 C (37.0 F)
n/a
n/a
Jul
43.3 C (109.9 F)
6.1 C (43.0 F)
n/a
n/a
Aug
41.7 C (107.1 F)
1.1 C (34.0 F)
n/a
n/a
Sep
38.9 C (102.0 F)
-1.1 C (30.0 F)
n/a
n/a
Oct
35.0 C (95.0 F)
-7.8 C (18.0 F)
n/a
n/a
Nov
28.9 C (84.0 F)
-19.4 C (-2.9 F)
n/a
n/a
Dec
23.3 C (73.9 F)
-30.0 C (-22.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Williamstown still stand. 1936 holds the most, with 61.
Standing records at Williamstown by the year they were set
Year set
Standing records
1902
14
1903
15
1904
7
1905
8
1906
15
1907
22
1908
13
1909
17
1910
23
1911
19
1912
27
1913
11
1914
23
1915
21
1916
21
1917
23
1918
32
1919
17
1920
11
1921
5
1922
11
1923
20
1924
11
1925
24
1926
7
1927
16
1928
15
1929
19
1930
44
1931
29
1932
16
1933
26
1934
43
1935
18
1936
61
1937
8
1938
11
1939
16
1940
15
1941
13
1942
14
1943
12
1944
9
1945
13
1946
9
1947
10
1948
9
1949
7
1950
17
1951
15
1952
16
1953
16
1954
14
1955
15
1956
12
1957
13
1958
16
1959
17
1960
17
1961
14
1962
16
1963
23
1964
13
1965
6
1966
11
1967
16
1968
5
1969
3
1970
8
1971
8
1972
19
1973
7
1974
17
1975
11
1976
11
1977
15
1978
4
1979
8
1980
11
1981
4
1982
18
1983
13
1984
12
1985
11
1986
12
1987
5
1988
8
1989
16
1990
9
1991
11
1992
8
1993
4
1994
4
1995
4
1996
12
1997
8
1998
14
1999
7
2000
11
2001
9
2002
12
2003
3
2004
5
All-Time Record Progression
8 new records
8 all-time records were set at Williamstown between 23 January 1936 and 1 March 1997. Each dot is a new record.
When Williamstown set new all-time records
Date
Kind
Detail
1936-01-23
Record low minimum temperature
Record low minimum temperature -26.7 C (-16.1 F)
1962-01-11
Record low maximum temperature
Record low maximum temperature -15.6 C (3.9 F)
1963-01-24
Record low minimum temperature
Record low minimum temperature -29.4 C (-20.9 F)
1977-01-17
Record low maximum temperature
Record low maximum temperature -16.7 C (1.9 F)
1982-01-17
Record low maximum temperature
Record low maximum temperature -17.8 C (0.0 F)
1989-12-22
Record low minimum temperature
Record low minimum temperature -30.0 C (-22.0 F)
1994-01-19
Record low minimum temperature
Record low minimum temperature -30.6 C (-23.1 F)
1997-03-01
Record daily precipitation
Record daily precipitation 152.4 mm (6.0 in)
Wettest Day of Each Month
Mar: 152.4 mm (6.0 in)
The wettest day on record for each calendar month at Williamstown. The most was 152.4 mm (6.0 in) on 1 March 1997.
Record daily precipitation for each month at Williamstown
Month
Record daily precipitation (mm)
Date
Jan
72.4 mm (2.9 in)
21 January 1933
Feb
88.1 mm (3.5 in)
18 February 2000
Mar
152.4 mm (6.0 in)
1 March 1997
Apr
77.7 mm (3.1 in)
2 April 1970
May
121.9 mm (4.8 in)
30 May 1927
Jun
107.7 mm (4.2 in)
23 June 1960
Jul
97.5 mm (3.8 in)
5 July 1957
Aug
105.4 mm (4.1 in)
3 August 1932
Sep
116.1 mm (4.6 in)
1 September 1965
Oct
95.3 mm (3.8 in)
2 October 1911
Nov
59.7 mm (2.4 in)
19 November 1957
Dec
79.2 mm (3.1 in)
23 December 1921
Period of Record Coverage
1902 to 2015
Complete yearUnder 90 percent of days
104 years of record at Williamstown, 1902 to 2015. 5 years have data for under 90 percent of days and are left out of rankings: 1902, 1921, 1949, 2004, 2015.
Cooler than the station meanWarmer than the station mean
One stripe for each of 96 complete years at Williamstown, 1903 to 2003. Blue stripes are years cooler than the station's own mean of 12.7 C (54.9 F); red stripes are warmer. The coolest year was 1958, at 10.4 C (50.7 F), and the warmest was 1938, at 14.8 C (58.7 F). The strongest colour marks a difference of 2.4 C (4.3 F).
Annual mean temperature at Williamstown as warming stripes, 1903 to 2003
Year
Annual mean temperature
Difference from the station mean
1903
12.3 C
-0.39 C
1904
11.8 C
-0.98 C
1905
12.1 C
-0.66 C
1906
12.5 C
-0.26 C
1907
11.5 C
-1.27 C
1908
12.7 C
-0.01 C
1909
12.2 C
-0.57 C
1910
11.3 C
-1.39 C
1911
12.7 C
-0.04 C
1912
10.8 C
-1.91 C
1914
12.3 C
-0.47 C
1915
12.3 C
-0.39 C
1916
12.4 C
-0.33 C
1917
10.9 C
-1.86 C
1918
13.0 C
+0.27 C
1919
14.2 C
+1.49 C
1920
12.4 C
-0.30 C
1922
13.6 C
+0.86 C
1924
11.8 C
-0.96 C
1925
13.0 C
+0.23 C
1926
12.1 C
-0.65 C
1927
13.0 C
+0.26 C
1929
12.1 C
-0.62 C
1930
13.9 C
+1.19 C
1931
14.2 C
+1.48 C
1932
13.6 C
+0.86 C
1933
14.5 C
+1.72 C
1934
14.3 C
+1.56 C
1935
13.6 C
+0.90 C
1936
13.9 C
+1.15 C
1937
12.9 C
+0.18 C
1938
14.8 C
+2.09 C
1939
14.2 C
+1.51 C
1940
12.3 C
-0.40 C
1941
13.9 C
+1.21 C
1942
13.3 C
+0.54 C
1943
13.3 C
+0.54 C
1944
13.7 C
+0.93 C
1945
12.9 C
+0.16 C
1946
14.1 C
+1.35 C
1947
12.5 C
-0.24 C
1948
13.2 C
+0.44 C
1950
11.7 C
-1.01 C
1951
12.8 C
+0.06 C
1952
13.7 C
+0.95 C
1953
14.0 C
+1.25 C
1954
12.9 C
+0.21 C
1955
12.1 C
-0.65 C
1956
12.0 C
-0.72 C
1957
12.0 C
-0.71 C
1958
10.4 C
-2.35 C
1959
12.2 C
-0.50 C
1960
11.0 C
-1.77 C
1961
11.3 C
-1.42 C
1962
11.4 C
-1.38 C
1963
10.8 C
-1.98 C
1964
12.3 C
-0.39 C
1965
11.9 C
-0.84 C
1966
11.6 C
-1.11 C
1967
12.4 C
-0.31 C
1968
12.3 C
-0.46 C
1969
12.2 C
-0.51 C
1970
12.8 C
+0.03 C
1971
12.8 C
+0.10 C
1972
12.2 C
-0.50 C
1973
13.3 C
+0.55 C
1974
12.7 C
+0.01 C
1975
13.0 C
+0.26 C
1976
11.9 C
-0.79 C
1977
12.4 C
-0.32 C
1978
11.4 C
-1.29 C
1979
11.7 C
-1.00 C
1980
12.2 C
-0.54 C
1981
12.3 C
-0.43 C
1982
12.7 C
-0.06 C
1983
12.7 C
-0.07 C
1984
12.7 C
-0.07 C
1985
12.5 C
-0.24 C
1986
13.5 C
+0.81 C
1987
13.8 C
+1.05 C
1988
12.7 C
-0.03 C
1989
12.2 C
-0.55 C
1990
13.8 C
+1.09 C
1991
14.2 C
+1.46 C
1992
12.8 C
+0.08 C
1993
12.8 C
+0.06 C
1994
13.2 C
+0.47 C
1995
13.1 C
+0.33 C
1996
12.5 C
-0.27 C
1997
12.7 C
-0.08 C
1998
14.6 C
+1.85 C
1999
14.3 C
+1.58 C
2000
13.2 C
+0.46 C
2001
14.0 C
+1.24 C
2002
14.0 C
+1.29 C
2003
13.0 C
+0.22 C
The fitted trend in annual mean temperature here over 1903 to 2003 is 0.05 C (-0.02 to 0.11) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: 0.08 F (-0.03 to 0.20) per decade. The slope is a straight line fitted to 96 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Williamstown
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.05 C (-0.02 to 0.11) per decade
0.08 F (-0.03 to 0.20) per decade
1903 to 2003
96
Not clearly different from zero
Mean daily maximum
-0.01 C (-0.08 to 0.07) per decade
-0.01 F (-0.15 to 0.13) per decade
1903 to 2003
96
Not clearly different from zero
Mean daily minimum
0.10 C (0.04 to 0.16) per decade
0.2 F (0.1 to 0.3) per decade
1903 to 2003
96
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
1902 to 2016
Yearly extremes at Williamstown: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
43.3 C (109.9 F)
1930
36.1 C (97.0 F)
104
Coldest night (TNn)
-30.6 C (-23.1 F)
1994
-19.4 C (-2.9 F)
104
Wettest day (Rx1day)
152.4 mm (6.0 in)
1997
59.1 mm (2.3 in)
106
Wettest five days (Rx5day)
320.9 mm (12.6 in)
1997
97.5 mm (3.8 in)
104
Longest dry spell (CDD)
33 days
1959
19 days
105
Hottest day (TXx)
The hottest day of the year at Williamstown, 1902 to 2016. The record is 43.3 C (109.9 F) in 1930, marked on the chart; the median year is 36.1 C (97.0 F).
Hottest day (TXx) at Williamstown by year
Year
Hottest day (TXx)
1902
37.2 C (99.0 F)
1903
36.7 C (98.1 F)
1904
35.0 C (95.0 F)
1905
32.8 C (91.0 F)
1906
33.9 C (93.0 F)
1907
33.9 C (93.0 F)
1908
36.7 C (98.1 F)
1909
33.9 C (93.0 F)
1910
33.3 C (91.9 F)
1911
36.7 C (98.1 F)
1912
35.0 C (95.0 F)
1913
37.8 C (100.0 F)
1914
40.0 C (104.0 F)
1915
36.7 C (98.1 F)
1916
36.1 C (97.0 F)
1917
36.1 C (97.0 F)
1918
40.6 C (105.1 F)
1919
37.2 C (99.0 F)
1920
35.0 C (95.0 F)
1921
36.7 C (98.1 F)
1922
35.6 C (96.1 F)
1923
36.7 C (98.1 F)
1924
36.7 C (98.1 F)
1925
37.2 C (99.0 F)
1926
37.2 C (99.0 F)
1927
36.1 C (97.0 F)
1928
33.3 C (91.9 F)
1929
35.6 C (96.1 F)
1930
43.3 C (109.9 F)
1931
38.9 C (102.0 F)
1932
38.9 C (102.0 F)
1933
41.1 C (106.0 F)
1934
43.3 C (109.9 F)
1935
37.2 C (99.0 F)
1936
42.8 C (109.0 F)
1937
36.7 C (98.1 F)
1938
37.8 C (100.0 F)
1939
37.8 C (100.0 F)
1940
37.8 C (100.0 F)
1941
37.2 C (99.0 F)
1942
37.8 C (100.0 F)
1943
38.3 C (100.9 F)
1944
38.3 C (100.9 F)
1945
34.4 C (93.9 F)
1946
35.6 C (96.1 F)
1947
35.0 C (95.0 F)
1948
38.3 C (100.9 F)
1949
35.0 C (95.0 F)
1950
32.8 C (91.0 F)
1951
36.7 C (98.1 F)
1952
39.4 C (102.9 F)
1953
38.3 C (100.9 F)
1954
40.0 C (104.0 F)
1955
35.0 C (95.0 F)
1956
33.9 C (93.0 F)
1957
36.1 C (97.0 F)
1958
32.2 C (90.0 F)
1959
36.1 C (97.0 F)
1960
35.6 C (96.1 F)
1961
33.9 C (93.0 F)
1962
36.7 C (98.1 F)
1963
33.9 C (93.0 F)
1964
38.3 C (100.9 F)
1965
36.7 C (98.1 F)
1966
38.9 C (102.0 F)
1967
33.3 C (91.9 F)
1968
33.9 C (93.0 F)
1969
33.9 C (93.0 F)
1970
36.7 C (98.1 F)
1971
35.0 C (95.0 F)
1972
34.4 C (93.9 F)
1973
33.3 C (91.9 F)
1974
32.2 C (90.0 F)
1975
32.8 C (91.0 F)
1976
33.9 C (93.0 F)
1977
33.9 C (93.0 F)
1978
33.3 C (91.9 F)
1979
33.9 C (93.0 F)
1980
36.7 C (98.1 F)
1981
34.4 C (93.9 F)
1982
33.9 C (93.0 F)
1983
40.0 C (104.0 F)
1984
34.4 C (93.9 F)
1985
34.4 C (93.9 F)
1986
35.6 C (96.1 F)
1987
37.8 C (100.0 F)
1988
40.0 C (104.0 F)
1989
33.9 C (93.0 F)
1990
35.0 C (95.0 F)
1991
36.7 C (98.1 F)
1992
32.8 C (91.0 F)
1993
35.0 C (95.0 F)
1994
35.6 C (96.1 F)
1995
37.2 C (99.0 F)
1996
35.6 C (96.1 F)
1997
37.8 C (100.0 F)
1998
35.0 C (95.0 F)
1999
40.0 C (104.0 F)
2000
33.3 C (91.9 F)
2001
33.3 C (91.9 F)
2002
37.8 C (100.0 F)
2003
35.6 C (96.1 F)
2004
32.2 C (90.0 F)
2005
n/a
2015
34.4 C (93.9 F)
2016
n/a
Coldest night (TNn)
The coldest night of the year at Williamstown, 1902 to 2016. The record is -30.6 C (-23.1 F) in 1994, marked on the chart; the median year is -19.4 C (-2.9 F).
Coldest night (TNn) at Williamstown by year
Year
Coldest night (TNn)
1902
-12.8 C (9.0 F)
1903
-22.8 C (-9.0 F)
1904
-19.4 C (-2.9 F)
1905
-22.2 C (-8.0 F)
1906
-19.4 C (-2.9 F)
1907
-19.4 C (-2.9 F)
1908
-16.7 C (1.9 F)
1909
-21.1 C (-6.0 F)
1910
-19.4 C (-2.9 F)
1911
-17.8 C (0.0 F)
1912
-25.6 C (-14.1 F)
1913
-17.2 C (1.0 F)
1914
-22.8 C (-9.0 F)
1915
-16.7 C (1.9 F)
1916
-20.6 C (-5.1 F)
1917
-23.3 C (-9.9 F)
1918
-26.1 C (-15.0 F)
1919
-16.1 C (3.0 F)
1920
-20.0 C (-4.0 F)
1921
-9.4 C (15.1 F)
1922
-15.0 C (5.0 F)
1923
-16.1 C (3.0 F)
1924
-17.8 C (0.0 F)
1925
-16.1 C (3.0 F)
1926
-20.0 C (-4.0 F)
1927
-16.1 C (3.0 F)
1928
-21.1 C (-6.0 F)
1929
-19.4 C (-2.9 F)
1930
-23.3 C (-9.9 F)
1931
-13.9 C (7.0 F)
1932
-22.2 C (-8.0 F)
1933
-22.8 C (-9.0 F)
1934
-22.8 C (-9.0 F)
1935
-22.8 C (-9.0 F)
1936
-26.7 C (-16.1 F)
1937
-14.4 C (6.1 F)
1938
-17.8 C (0.0 F)
1939
-15.0 C (5.0 F)
1940
-26.1 C (-15.0 F)
1941
-13.9 C (7.0 F)
1942
-25.6 C (-14.1 F)
1943
-18.3 C (-0.9 F)
1944
-16.7 C (1.9 F)
1945
-20.0 C (-4.0 F)
1946
-16.1 C (3.0 F)
1947
-18.3 C (-0.9 F)
1948
-18.9 C (-2.0 F)
1949
-14.4 C (6.1 F)
1950
-18.3 C (-0.9 F)
1951
-25.6 C (-14.1 F)
1952
-16.1 C (3.0 F)
1953
-17.8 C (0.0 F)
1954
-17.8 C (0.0 F)
1955
-18.9 C (-2.0 F)
1956
-13.3 C (8.1 F)
1957
-21.1 C (-6.0 F)
1958
-21.1 C (-6.0 F)
1959
-22.2 C (-8.0 F)
1960
-21.7 C (-7.1 F)
1961
-22.8 C (-9.0 F)
1962
-24.4 C (-11.9 F)
1963
-29.4 C (-20.9 F)
1964
-16.7 C (1.9 F)
1965
-22.8 C (-9.0 F)
1966
-24.4 C (-11.9 F)
1967
-20.6 C (-5.1 F)
1968
-22.2 C (-8.0 F)
1969
-17.2 C (1.0 F)
1970
-21.7 C (-7.1 F)
1971
-20.6 C (-5.1 F)
1972
-25.0 C (-13.0 F)
1973
-16.7 C (1.9 F)
1974
-12.8 C (9.0 F)
1975
-14.4 C (6.1 F)
1976
-20.6 C (-5.1 F)
1977
-28.9 C (-20.0 F)
1978
-21.7 C (-7.1 F)
1979
-21.1 C (-6.0 F)
1980
-18.3 C (-0.9 F)
1981
-22.2 C (-8.0 F)
1982
-27.8 C (-18.0 F)
1983
-26.1 C (-15.0 F)
1984
-26.1 C (-15.0 F)
1985
-29.4 C (-20.9 F)
1986
-17.8 C (0.0 F)
1987
-17.2 C (1.0 F)
1988
-20.0 C (-4.0 F)
1989
-30.0 C (-22.0 F)
1990
-13.9 C (7.0 F)
1991
-17.8 C (0.0 F)
1992
-19.4 C (-2.9 F)
1993
-16.7 C (1.9 F)
1994
-30.6 C (-23.1 F)
1995
-18.9 C (-2.0 F)
1996
-23.3 C (-9.9 F)
1997
-18.9 C (-2.0 F)
1998
-13.3 C (8.1 F)
1999
-19.4 C (-2.9 F)
2000
-18.3 C (-0.9 F)
2001
-15.0 C (5.0 F)
2002
-14.4 C (6.1 F)
2003
-21.1 C (-6.0 F)
2004
-12.8 C (9.0 F)
2005
n/a
2015
9.4 C (48.9 F)
2016
n/a
Wettest day (Rx1day)
The wettest day of the year at Williamstown, 1902 to 2016. The record is 152.4 mm (6.0 in) in 1997, marked on the chart; the median year is 59.1 mm (2.3 in).
Wettest day (Rx1day) at Williamstown by year
Year
Wettest day (Rx1day)
1902
57.4 mm (2.3 in)
1903
77.0 mm (3.0 in)
1904
45.7 mm (1.8 in)
1905
69.9 mm (2.8 in)
1906
81.3 mm (3.2 in)
1907
49.0 mm (1.9 in)
1908
41.9 mm (1.6 in)
1909
87.1 mm (3.4 in)
1910
49.3 mm (1.9 in)
1911
95.3 mm (3.8 in)
1912
45.7 mm (1.8 in)
1913
75.4 mm (3.0 in)
1914
68.6 mm (2.7 in)
1915
66.3 mm (2.6 in)
1916
50.8 mm (2.0 in)
1917
81.8 mm (3.2 in)
1918
45.7 mm (1.8 in)
1919
54.6 mm (2.1 in)
1920
51.6 mm (2.0 in)
1921
81.3 mm (3.2 in)
1922
49.5 mm (1.9 in)
1923
46.7 mm (1.8 in)
1924
36.1 mm (1.4 in)
1925
67.1 mm (2.6 in)
1926
53.3 mm (2.1 in)
1927
121.9 mm (4.8 in)
1928
59.9 mm (2.4 in)
1929
50.3 mm (2.0 in)
1930
42.4 mm (1.7 in)
1931
40.6 mm (1.6 in)
1932
105.4 mm (4.1 in)
1933
72.4 mm (2.9 in)
1934
35.6 mm (1.4 in)
1935
68.6 mm (2.7 in)
1936
44.5 mm (1.8 in)
1937
66.0 mm (2.6 in)
1938
58.4 mm (2.3 in)
1939
86.4 mm (3.4 in)
1940
80.0 mm (3.1 in)
1941
86.4 mm (3.4 in)
1942
43.2 mm (1.7 in)
1943
93.0 mm (3.7 in)
1944
42.9 mm (1.7 in)
1945
92.7 mm (3.6 in)
1946
45.7 mm (1.8 in)
1947
39.9 mm (1.6 in)
1948
65.3 mm (2.6 in)
1949
59.2 mm (2.3 in)
1950
62.2 mm (2.4 in)
1951
53.3 mm (2.1 in)
1952
50.8 mm (2.0 in)
1953
50.8 mm (2.0 in)
1954
43.2 mm (1.7 in)
1955
70.4 mm (2.8 in)
1956
90.2 mm (3.6 in)
1957
97.5 mm (3.8 in)
1958
40.9 mm (1.6 in)
1959
45.7 mm (1.8 in)
1960
107.7 mm (4.2 in)
1961
96.5 mm (3.8 in)
1962
59.7 mm (2.4 in)
1963
58.9 mm (2.3 in)
1964
104.9 mm (4.1 in)
1965
116.1 mm (4.6 in)
1966
53.1 mm (2.1 in)
1967
62.7 mm (2.5 in)
1968
46.2 mm (1.8 in)
1969
42.7 mm (1.7 in)
1970
77.7 mm (3.1 in)
1971
65.8 mm (2.6 in)
1972
50.0 mm (2.0 in)
1973
83.6 mm (3.3 in)
1974
60.7 mm (2.4 in)
1975
77.7 mm (3.1 in)
1976
63.5 mm (2.5 in)
1977
79.2 mm (3.1 in)
1978
66.3 mm (2.6 in)
1979
98.8 mm (3.9 in)
1980
53.3 mm (2.1 in)
1981
48.0 mm (1.9 in)
1982
95.3 mm (3.8 in)
1983
66.0 mm (2.6 in)
1984
66.0 mm (2.6 in)
1985
68.1 mm (2.7 in)
1986
39.4 mm (1.6 in)
1987
41.7 mm (1.6 in)
1988
69.9 mm (2.8 in)
1989
53.1 mm (2.1 in)
1990
70.6 mm (2.8 in)
1991
43.7 mm (1.7 in)
1992
55.9 mm (2.2 in)
1993
48.0 mm (1.9 in)
1994
58.7 mm (2.3 in)
1995
52.1 mm (2.1 in)
1996
61.0 mm (2.4 in)
1997
152.4 mm (6.0 in)
1998
49.3 mm (1.9 in)
1999
40.4 mm (1.6 in)
2000
88.1 mm (3.5 in)
2001
51.3 mm (2.0 in)
2002
53.1 mm (2.1 in)
2003
67.3 mm (2.6 in)
2004
50.8 mm (2.0 in)
2005
0.0 mm (0.00 in)
2015
47.8 mm (1.9 in)
2016
5.3 mm (0.21 in)
Wettest five days (Rx5day)
The wettest five days of the year at Williamstown, 1902 to 2016. The record is 320.9 mm (12.6 in) in 1997, marked on the chart; the median year is 97.5 mm (3.8 in).
Wettest five days (Rx5day) at Williamstown by year
Year
Wettest five days (Rx5day)
1902
92.8 mm (3.7 in)
1903
77.0 mm (3.0 in)
1904
75.0 mm (3.0 in)
1905
106.7 mm (4.2 in)
1906
98.6 mm (3.9 in)
1907
109.3 mm (4.3 in)
1908
66.3 mm (2.6 in)
1909
76.4 mm (3.0 in)
1910
76.0 mm (3.0 in)
1911
159.8 mm (6.3 in)
1912
97.6 mm (3.8 in)
1913
107.2 mm (4.2 in)
1914
163.9 mm (6.5 in)
1915
94.0 mm (3.7 in)
1916
80.5 mm (3.2 in)
1917
129.5 mm (5.1 in)
1918
69.4 mm (2.7 in)
1919
97.5 mm (3.8 in)
1920
105.8 mm (4.2 in)
1921
146.2 mm (5.8 in)
1922
68.3 mm (2.7 in)
1923
58.1 mm (2.3 in)
1924
87.7 mm (3.5 in)
1925
104.8 mm (4.1 in)
1926
71.1 mm (2.8 in)
1927
142.3 mm (5.6 in)
1928
83.8 mm (3.3 in)
1929
95.7 mm (3.8 in)
1930
49.3 mm (1.9 in)
1931
73.9 mm (2.9 in)
1932
145.3 mm (5.7 in)
1933
129.1 mm (5.1 in)
1934
72.2 mm (2.8 in)
1935
111.2 mm (4.4 in)
1936
86.4 mm (3.4 in)
1937
215.5 mm (8.5 in)
1938
90.1 mm (3.5 in)
1939
127.4 mm (5.0 in)
1940
116.6 mm (4.6 in)
1941
119.1 mm (4.7 in)
1942
65.1 mm (2.6 in)
1943
111.2 mm (4.4 in)
1944
60.5 mm (2.4 in)
1945
145.5 mm (5.7 in)
1946
61.2 mm (2.4 in)
1947
58.2 mm (2.3 in)
1948
131.6 mm (5.2 in)
1949
114.6 mm (4.5 in)
1950
105.5 mm (4.2 in)
1951
69.3 mm (2.7 in)
1952
70.7 mm (2.8 in)
1953
105.1 mm (4.1 in)
1954
68.1 mm (2.7 in)
1955
111.0 mm (4.4 in)
1956
132.8 mm (5.2 in)
1957
110.3 mm (4.3 in)
1958
75.9 mm (3.0 in)
1959
93.8 mm (3.7 in)
1960
123.1 mm (4.8 in)
1961
174.0 mm (6.9 in)
1962
116.3 mm (4.6 in)
1963
82.3 mm (3.2 in)
1964
176.8 mm (7.0 in)
1965
116.4 mm (4.6 in)
1966
85.9 mm (3.4 in)
1967
68.5 mm (2.7 in)
1968
102.2 mm (4.0 in)
1969
89.5 mm (3.5 in)
1970
111.7 mm (4.4 in)
1971
92.7 mm (3.6 in)
1972
96.5 mm (3.8 in)
1973
130.1 mm (5.1 in)
1974
94.4 mm (3.7 in)
1975
99.8 mm (3.9 in)
1976
87.9 mm (3.5 in)
1977
130.0 mm (5.1 in)
1978
102.3 mm (4.0 in)
1979
116.8 mm (4.6 in)
1980
65.0 mm (2.6 in)
1981
72.9 mm (2.9 in)
1982
99.1 mm (3.9 in)
1983
182.3 mm (7.2 in)
1984
93.7 mm (3.7 in)
1985
93.5 mm (3.7 in)
1986
77.6 mm (3.1 in)
1987
69.1 mm (2.7 in)
1988
110.3 mm (4.3 in)
1989
112.5 mm (4.4 in)
1990
93.6 mm (3.7 in)
1991
92.7 mm (3.6 in)
1992
71.2 mm (2.8 in)
1993
97.4 mm (3.8 in)
1994
111.6 mm (4.4 in)
1995
79.5 mm (3.1 in)
1996
113.1 mm (4.5 in)
1997
320.9 mm (12.6 in)
1998
108.5 mm (4.3 in)
1999
67.4 mm (2.7 in)
2000
126.2 mm (5.0 in)
2001
66.4 mm (2.6 in)
2002
86.6 mm (3.4 in)
2003
110.2 mm (4.3 in)
2004
100.8 mm (4.0 in)
2005
0.0 mm (0.00 in)
2015
n/a
2016
n/a
Longest dry spell (CDD)
The longest dry spell of the year at Williamstown, 1902 to 2016. The record is 33 days in 1959, marked on the chart; the median year is 19 days.
Longest dry spell (CDD) at Williamstown by year
Year
Longest dry spell (CDD)
1902
21 days
1903
20 days
1904
21 days
1905
13 days
1906
26 days
1907
18 days
1908
23 days
1909
16 days
1910
16 days
1911
19 days
1912
24 days
1913
20 days
1914
23 days
1915
25 days
1916
21 days
1917
28 days
1918
17 days
1919
24 days
1920
26 days
1921
12 days
1922
21 days
1923
26 days
1924
26 days
1925
20 days
1926
12 days
1927
19 days
1928
20 days
1929
19 days
1930
23 days
1931
18 days
1932
19 days
1933
21 days
1934
25 days
1935
17 days
1936
27 days
1937
14 days
1938
19 days
1939
19 days
1940
14 days
1941
22 days
1942
23 days
1943
19 days
1944
24 days
1945
20 days
1946
13 days
1947
17 days
1948
26 days
1949
16 days
1950
14 days
1951
14 days
1952
29 days
1953
27 days
1954
20 days
1955
18 days
1956
16 days
1957
23 days
1958
14 days
1959
33 days
1960
13 days
1961
16 days
1962
12 days
1963
19 days
1964
22 days
1965
16 days
1966
16 days
1967
20 days
1968
17 days
1969
13 days
1970
17 days
1971
12 days
1972
14 days
1973
14 days
1974
15 days
1975
13 days
1976
23 days
1977
21 days
1978
20 days
1979
11 days
1980
14 days
1981
20 days
1982
19 days
1983
13 days
1984
20 days
1985
23 days
1986
16 days
1987
21 days
1988
23 days
1989
12 days
1990
10 days
1991
13 days
1992
19 days
1993
18 days
1994
16 days
1995
19 days
1996
11 days
1997
14 days
1998
19 days
1999
19 days
2000
19 days
2001
16 days
2002
15 days
2003
11 days
2004
22 days
2005
31 days
2015
4 days
2016
n/a
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
96 years with a frost
Across 96 years with a frost, the median last spring frost at Williamstown falls on 20 April and the median first autumn frost on 24 October, which leaves a median of 186 days between them.
In 1974 to 2003 the median growing season was 184 days. That is 2 days more than in 1903 to 1936.
Fitted over all years, the growing season changes by +0.7 days per decade at this station.
Frost dates and growing season at Williamstown
Measure
Median, all years
Earliest period (1903 to 1936)
Recent period (1974 to 2003)
Recent against earliest
Fitted trend
Last spring frost
20 April
25 April
16 April
9 days earlier
-0.9 days per decade
First autumn frost
24 October
24 October
19 October
5 days earlier
-0.3 days per decade
Growing days
186 days
182 days
184 days
2 days more
+0.7 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
94 years, 1903 to 2003
A day with at least 59.6 mm (2.3 in) of rain is expected about once in 2 years. A day with at least 142.5 mm (5.6 in) of rain is expected about once in 100 years.
Rainfall return levels at Williamstown: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
59.6 mm (2.3 in)
5 years
78.4 mm (3.1 in)
10 years
92.1 mm (3.6 in)
25 years
111.0 mm (4.4 in)
50 years
126.2 mm (5.0 in)
100 years
142.5 mm (5.6 in)
Longer than the 94 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, 94 years of values from 1903 to 2003.
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: 152.4 mm (6.0 in) in 1997; 121.9 mm (4.8 in) in 1927; 116.1 mm (4.6 in) in 1965.
Download the Data
Data for Williamstown standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Williamstown 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 2026-10-16 (16 October 2026). Records are computed by this site and are not official.