Record envelope, standing records and threshold days for Diversion Dam (USC00482595), Wyoming, United States, with 105 years of record.
Key Facts for Diversion Dam
Diversion Dam (USC00482595) is a weather station in Wyoming, United States at 43.23 latitude and -108.95 longitude, 1,704 m (5,589 ft) above sea level.
The station reports from 1920 to 2024, 105 years of record.
1,464 records set at Diversion Dam still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Diversion Dam set a daily record precipitation of 27.9 mm (1.1 in) on 3 February 2024.
About the Station
Location: Wyoming, United States, 43.23 latitude, -108.95 longitude.
Elevation: 1,704 m (5,589 ft).
Period of record: 1920 to 2024, 105 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 Diversion Dam. 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 Diversion Dam, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
17.8 C (64.0 F)
-42.8 C (-45.0 F)
n/a
n/a
Feb
21.1 C (70.0 F)
-41.7 C (-43.1 F)
n/a
n/a
Mar
23.9 C (75.0 F)
-30.6 C (-23.1 F)
n/a
n/a
Apr
27.8 C (82.0 F)
-23.3 C (-9.9 F)
n/a
n/a
May
33.3 C (91.9 F)
-8.3 C (17.1 F)
n/a
n/a
Jun
36.7 C (98.1 F)
-2.8 C (27.0 F)
n/a
n/a
Jul
37.8 C (100.0 F)
0.6 C (33.1 F)
n/a
n/a
Aug
37.8 C (100.0 F)
-2.8 C (27.0 F)
n/a
n/a
Sep
37.8 C (100.0 F)
-12.2 C (10.0 F)
n/a
n/a
Oct
30.0 C (86.0 F)
-22.2 C (-8.0 F)
n/a
n/a
Nov
22.2 C (72.0 F)
-32.2 C (-26.0 F)
n/a
n/a
Dec
18.9 C (66.0 F)
-42.2 C (-44.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Diversion Dam still stand. 1985 holds the most, with 61.
Standing records at Diversion Dam by the year they were set
Year set
Standing records
1920
2
1921
24
1922
9
1923
3
1924
19
1925
17
1926
27
1927
14
1928
6
1929
10
1930
13
1931
18
1932
31
1933
24
1934
12
1935
24
1936
25
1937
18
1938
5
1939
21
1940
20
1948
13
1949
23
1950
25
1951
15
1952
12
1953
13
1954
19
1955
13
1956
9
1957
3
1958
9
1959
16
1960
19
1961
8
1962
18
1963
20
1964
8
1965
25
1966
21
1967
7
1968
8
1969
14
1970
12
1971
10
1972
24
1973
12
1974
5
1975
10
1976
15
1977
12
1978
19
1979
17
1980
27
1981
3
1982
11
1983
20
1984
10
1985
61
1986
61
1987
51
1988
3
1990
15
1991
10
1992
12
1993
17
1994
6
1995
17
1996
21
1997
18
1998
5
1999
17
2000
10
2001
12
2002
28
2003
12
2004
12
2005
10
2006
9
2007
19
2008
11
2009
15
2010
7
2011
6
2012
6
2014
17
2015
12
2016
6
2017
18
2018
14
2019
13
2020
17
2022
8
2023
18
2024
3
All-Time Record Progression
8 new records
8 all-time records were set at Diversion Dam between 12 January 1963 and 7 May 2016. Each dot is a new record.
When Diversion Dam set new all-time records
Date
Kind
Detail
1963-01-12
Record low maximum temperature
Record low maximum temperature -28.9 C (-20.0 F)
1976-08-01
Record daily precipitation
Record daily precipitation 66.8 mm (2.6 in)
1977-07-18
Record high minimum temperature
Record high minimum temperature 21.1 C (70.0 F)
1978-12-05
Record daily snowfall
Record daily snowfall 30.5 cm (12.0 in)
1983-05-11
Record daily snowfall
Record daily snowfall 35.6 cm (14.0 in)
1985-07-07
Record high minimum temperature
Record high minimum temperature 22.2 C (72.0 F)
1986-08-15
Record high minimum temperature
Record high minimum temperature 22.8 C (73.0 F)
2016-05-07
Record daily precipitation
Record daily precipitation 77.2 mm (3.0 in)
Wettest Day of Each Month
May: 77.2 mm (3.0 in)
The wettest day on record for each calendar month at Diversion Dam. The most was 77.2 mm (3.0 in) on 7 May 2016.
Record daily precipitation for each month at Diversion Dam
Month
Record daily precipitation (mm)
Date
Jan
20.3 mm (0.8 in)
8 January 1962
Feb
28.4 mm (1.1 in)
24 February 2023
Mar
58.7 mm (2.3 in)
31 March 2017
Apr
47.0 mm (1.9 in)
26 April 1991
May
77.2 mm (3.0 in)
7 May 2016
Jun
61.7 mm (2.4 in)
15 June 1992
Jul
58.9 mm (2.3 in)
25 July 1923
Aug
66.8 mm (2.6 in)
1 August 1976
Sep
56.6 mm (2.2 in)
20 September 1950
Oct
42.7 mm (1.7 in)
31 October 1936
Nov
22.9 mm (0.9 in)
7 November 1920
Dec
18.8 mm (0.7 in)
12 December 1992
Period of Record Coverage
1920 to 2024
Complete yearUnder 90 percent of days
96 years of record at Diversion Dam, 1920 to 2024. 26 years have data for under 90 percent of days and are left out of rankings: 1920, 1936, 1948, 1969, 1985, 1986, 1987, 1988 and others.
Cooler than the station meanWarmer than the station mean
One stripe for each of 68 complete years at Diversion Dam, 1921 to 2023. Blue stripes are years cooler than the station's own mean of 6.6 C (43.8 F); red stripes are warmer. The coolest year was 1993, at 4.0 C (39.2 F), and the warmest was 1986, at 8.6 C (47.4 F). The strongest colour marks a difference of 2.6 C (4.7 F).
Annual mean temperature at Diversion Dam as warming stripes, 1921 to 2023
Year
Annual mean temperature
Difference from the station mean
1921
7.7 C
+1.08 C
1922
5.9 C
-0.64 C
1923
6.0 C
-0.62 C
1924
5.7 C
-0.90 C
1925
7.6 C
+1.04 C
1926
7.8 C
+1.22 C
1927
6.4 C
-0.19 C
1928
5.8 C
-0.74 C
1929
5.4 C
-1.22 C
1930
6.1 C
-0.48 C
1931
6.1 C
-0.46 C
1932
4.9 C
-1.65 C
1933
7.1 C
+0.51 C
1934
8.0 C
+1.43 C
1935
6.3 C
-0.29 C
1937
5.8 C
-0.78 C
1938
7.2 C
+0.61 C
1939
7.5 C
+0.93 C
1940
7.6 C
+0.99 C
1949
5.9 C
-0.64 C
1950
6.4 C
-0.20 C
1951
5.8 C
-0.75 C
1952
6.6 C
-0.01 C
1953
8.0 C
+1.47 C
1954
8.0 C
+1.42 C
1955
6.5 C
-0.08 C
1956
7.0 C
+0.42 C
1957
6.8 C
+0.19 C
1958
7.6 C
+1.07 C
1959
6.5 C
-0.03 C
1960
6.8 C
+0.21 C
1962
6.6 C
+0.02 C
1963
7.1 C
+0.53 C
1964
6.4 C
-0.20 C
1965
6.7 C
+0.15 C
1966
7.4 C
+0.84 C
1967
7.1 C
+0.54 C
1968
6.2 C
-0.40 C
1970
6.9 C
+0.28 C
1971
6.7 C
+0.15 C
1973
5.4 C
-1.13 C
1974
7.1 C
+0.53 C
1975
6.1 C
-0.44 C
1976
7.6 C
+1.03 C
1977
7.7 C
+1.08 C
1979
6.3 C
-0.28 C
1980
7.2 C
+0.58 C
1981
8.3 C
+1.72 C
1982
6.3 C
-0.30 C
1983
6.3 C
-0.30 C
1984
6.4 C
-0.19 C
1986
8.6 C
+2.01 C
1993
4.0 C
-2.59 C
1994
6.8 C
+0.25 C
1995
5.7 C
-0.92 C
1996
5.4 C
-1.14 C
1997
5.7 C
-0.87 C
1998
6.3 C
-0.29 C
1999
7.0 C
+0.39 C
2002
5.3 C
-1.32 C
2007
7.5 C
+0.88 C
2008
6.2 C
-0.40 C
2010
6.2 C
-0.36 C
2015
7.0 C
+0.43 C
2017
6.4 C
-0.15 C
2018
6.3 C
-0.24 C
2019
5.7 C
-0.86 C
2023
4.8 C
-1.76 C
The fitted trend in annual mean temperature here over 1921 to 2023 is -0.05 C (-0.12 to 0.03) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: -0.09 F (-0.22 to 0.05) per decade. The slope is a straight line fitted to 68 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Diversion Dam
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
-0.05 C (-0.12 to 0.03) per decade
-0.09 F (-0.22 to 0.05) per decade
1921 to 2023
68
Not clearly different from zero
Mean daily maximum
-0.07 C (-0.16 to 0.02) per decade
-0.13 F (-0.28 to 0.03) per decade
1921 to 2023
68
Not clearly different from zero
Mean daily minimum
-0.02 C (-0.10 to 0.05) per decade
-0.05 F (-0.18 to 0.09) per decade
1921 to 2023
68
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
1920 to 2024
Yearly extremes at Diversion Dam: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
37.8 C (100.0 F)
1925
35.0 C (95.0 F)
96
Coldest night (TNn)
-42.8 C (-45.0 F)
1930
-31.7 C (-25.1 F)
96
Wettest day (Rx1day)
77.2 mm (3.0 in)
2016
27.9 mm (1.1 in)
97
Wettest five days (Rx5day)
106.4 mm (4.2 in)
1924
39.9 mm (1.6 in)
96
Longest dry spell (CDD)
98 days
1960
47 days
97
Hottest day (TXx)
The hottest day of the year at Diversion Dam, 1920 to 2024. The record is 37.8 C (100.0 F) in 1925, marked on the chart; the median year is 35.0 C (95.0 F).
Hottest day (TXx) at Diversion Dam by year
Year
Hottest day (TXx)
1920
30.0 C (86.0 F)
1921
35.6 C (96.1 F)
1922
36.1 C (97.0 F)
1923
34.4 C (93.9 F)
1924
33.3 C (91.9 F)
1925
37.8 C (100.0 F)
1926
36.7 C (98.1 F)
1927
36.1 C (97.0 F)
1928
35.0 C (95.0 F)
1929
35.6 C (96.1 F)
1930
35.0 C (95.0 F)
1931
37.8 C (100.0 F)
1932
34.4 C (93.9 F)
1933
36.1 C (97.0 F)
1934
36.1 C (97.0 F)
1935
35.6 C (96.1 F)
1936
35.6 C (96.1 F)
1937
37.2 C (99.0 F)
1938
36.7 C (98.1 F)
1939
37.2 C (99.0 F)
1940
37.8 C (100.0 F)
1948
34.4 C (93.9 F)
1949
35.6 C (96.1 F)
1950
34.4 C (93.9 F)
1951
34.4 C (93.9 F)
1952
35.6 C (96.1 F)
1953
36.1 C (97.0 F)
1954
37.8 C (100.0 F)
1955
36.7 C (98.1 F)
1956
34.4 C (93.9 F)
1957
34.4 C (93.9 F)
1958
34.4 C (93.9 F)
1959
37.8 C (100.0 F)
1960
37.2 C (99.0 F)
1961
35.0 C (95.0 F)
1962
36.1 C (97.0 F)
1963
34.4 C (93.9 F)
1964
35.6 C (96.1 F)
1965
34.4 C (93.9 F)
1966
36.7 C (98.1 F)
1967
33.9 C (93.0 F)
1968
34.4 C (93.9 F)
1969
34.4 C (93.9 F)
1970
35.0 C (95.0 F)
1971
33.3 C (91.9 F)
1972
35.0 C (95.0 F)
1973
35.0 C (95.0 F)
1974
34.4 C (93.9 F)
1975
33.9 C (93.0 F)
1976
36.1 C (97.0 F)
1977
36.1 C (97.0 F)
1978
35.0 C (95.0 F)
1979
37.2 C (99.0 F)
1980
34.4 C (93.9 F)
1981
34.4 C (93.9 F)
1982
35.0 C (95.0 F)
1983
35.0 C (95.0 F)
1984
35.0 C (95.0 F)
1985
32.8 C (91.0 F)
1986
34.4 C (93.9 F)
1987
33.9 C (93.0 F)
1988
19.4 C (66.9 F)
1989
n/a
1990
33.9 C (93.0 F)
1991
32.8 C (91.0 F)
1992
32.2 C (90.0 F)
1993
31.1 C (88.0 F)
1994
32.8 C (91.0 F)
1995
33.9 C (93.0 F)
1996
34.4 C (93.9 F)
1997
35.6 C (96.1 F)
1998
35.6 C (96.1 F)
1999
33.9 C (93.0 F)
2000
35.0 C (95.0 F)
2001
35.6 C (96.1 F)
2002
36.7 C (98.1 F)
2003
37.2 C (99.0 F)
2004
33.9 C (93.0 F)
2005
36.1 C (97.0 F)
2006
37.2 C (99.0 F)
2007
34.4 C (93.9 F)
2008
35.0 C (95.0 F)
2009
32.8 C (91.0 F)
2010
33.9 C (93.0 F)
2011
34.4 C (93.9 F)
2012
35.6 C (96.1 F)
2013
17.8 C (64.0 F)
2014
36.1 C (97.0 F)
2015
35.6 C (96.1 F)
2016
32.8 C (91.0 F)
2017
35.6 C (96.1 F)
2018
36.7 C (98.1 F)
2019
35.6 C (96.1 F)
2020
37.8 C (100.0 F)
2022
37.8 C (100.0 F)
2023
35.6 C (96.1 F)
2024
10.0 C (50.0 F)
Coldest night (TNn)
The coldest night of the year at Diversion Dam, 1920 to 2024. The record is -42.8 C (-45.0 F) in 1930, marked on the chart; the median year is -31.7 C (-25.1 F).
Coldest night (TNn) at Diversion Dam by year
Year
Coldest night (TNn)
1920
-28.9 C (-20.0 F)
1921
-28.9 C (-20.0 F)
1922
-35.6 C (-32.1 F)
1923
-35.6 C (-32.1 F)
1924
-41.1 C (-42.0 F)
1925
-18.9 C (-2.0 F)
1926
-35.6 C (-32.1 F)
1927
-33.9 C (-29.0 F)
1928
-28.3 C (-18.9 F)
1929
-31.7 C (-25.1 F)
1930
-42.8 C (-45.0 F)
1931
-26.7 C (-16.1 F)
1932
-37.2 C (-35.0 F)
1933
-41.7 C (-43.1 F)
1934
-26.1 C (-15.0 F)
1935
-34.4 C (-29.9 F)
1936
-41.1 C (-42.0 F)
1937
-36.1 C (-33.0 F)
1938
-25.6 C (-14.1 F)
1939
-32.8 C (-27.0 F)
1940
-32.8 C (-27.0 F)
1948
-28.3 C (-18.9 F)
1949
-38.3 C (-36.9 F)
1950
-30.0 C (-22.0 F)
1951
-33.9 C (-29.0 F)
1952
-31.7 C (-25.1 F)
1953
-21.7 C (-7.1 F)
1954
-29.4 C (-20.9 F)
1955
-27.8 C (-18.0 F)
1956
-30.6 C (-23.1 F)
1957
-28.9 C (-20.0 F)
1958
-22.2 C (-8.0 F)
1959
-36.1 C (-33.0 F)
1960
-31.1 C (-24.0 F)
1961
-32.2 C (-26.0 F)
1962
-38.9 C (-38.0 F)
1963
-38.9 C (-38.0 F)
1964
-36.1 C (-33.0 F)
1965
-29.4 C (-20.9 F)
1966
-28.9 C (-20.0 F)
1967
-29.4 C (-20.9 F)
1968
-32.2 C (-26.0 F)
1969
-26.1 C (-15.0 F)
1970
-27.8 C (-18.0 F)
1971
-29.4 C (-20.9 F)
1972
-37.2 C (-35.0 F)
1973
-34.4 C (-29.9 F)
1974
-33.9 C (-29.0 F)
1975
-28.9 C (-20.0 F)
1976
-33.3 C (-27.9 F)
1977
-32.2 C (-26.0 F)
1978
-37.2 C (-35.0 F)
1979
-36.7 C (-34.1 F)
1980
-36.7 C (-34.1 F)
1981
-28.3 C (-18.9 F)
1982
-33.3 C (-27.9 F)
1983
-36.7 C (-34.1 F)
1984
-37.8 C (-36.0 F)
1985
-34.4 C (-29.9 F)
1986
-24.4 C (-11.9 F)
1987
-25.6 C (-14.1 F)
1988
-27.8 C (-18.0 F)
1989
n/a
1990
-42.2 C (-44.0 F)
1991
-28.3 C (-18.9 F)
1992
-32.2 C (-26.0 F)
1993
-33.3 C (-27.9 F)
1994
-25.0 C (-13.0 F)
1995
-27.2 C (-17.0 F)
1996
-35.0 C (-31.0 F)
1997
-27.8 C (-18.0 F)
1998
-36.7 C (-34.1 F)
1999
-16.7 C (1.9 F)
2000
-26.1 C (-15.0 F)
2001
-29.4 C (-20.9 F)
2002
-27.2 C (-17.0 F)
2003
-27.8 C (-18.0 F)
2004
-27.2 C (-17.0 F)
2005
-25.6 C (-14.1 F)
2006
-31.1 C (-24.0 F)
2007
-33.9 C (-29.0 F)
2008
-32.2 C (-26.0 F)
2009
-33.3 C (-27.9 F)
2010
-31.1 C (-24.0 F)
2011
-31.7 C (-25.1 F)
2012
-21.1 C (-6.0 F)
2013
-25.0 C (-13.0 F)
2014
-33.9 C (-29.0 F)
2015
-29.4 C (-20.9 F)
2016
-35.0 C (-31.0 F)
2017
-35.6 C (-32.1 F)
2018
-31.7 C (-25.1 F)
2019
-29.4 C (-20.9 F)
2020
-27.2 C (-17.0 F)
2022
-36.1 C (-33.0 F)
2023
-37.2 C (-35.0 F)
2024
-32.8 C (-27.0 F)
Wettest day (Rx1day)
The wettest day of the year at Diversion Dam, 1920 to 2024. The record is 77.2 mm (3.0 in) in 2016, marked on the chart; the median year is 27.9 mm (1.1 in).
Wettest day (Rx1day) at Diversion Dam by year
Year
Wettest day (Rx1day)
1920
39.4 mm (1.6 in)
1921
27.9 mm (1.1 in)
1922
31.8 mm (1.3 in)
1923
58.9 mm (2.3 in)
1924
50.8 mm (2.0 in)
1925
30.5 mm (1.2 in)
1926
10.2 mm (0.4 in)
1927
40.1 mm (1.6 in)
1928
28.7 mm (1.1 in)
1929
24.4 mm (1.0 in)
1930
34.8 mm (1.4 in)
1931
27.9 mm (1.1 in)
1932
17.0 mm (0.7 in)
1933
20.3 mm (0.8 in)
1934
17.3 mm (0.7 in)
1935
16.8 mm (0.7 in)
1936
42.7 mm (1.7 in)
1937
27.4 mm (1.1 in)
1938
17.0 mm (0.7 in)
1939
37.1 mm (1.5 in)
1940
44.5 mm (1.8 in)
1948
19.8 mm (0.8 in)
1949
21.3 mm (0.8 in)
1950
56.6 mm (2.2 in)
1951
30.0 mm (1.2 in)
1952
20.8 mm (0.8 in)
1953
21.6 mm (0.9 in)
1954
17.0 mm (0.7 in)
1955
27.4 mm (1.1 in)
1956
19.1 mm (0.8 in)
1957
36.1 mm (1.4 in)
1958
27.2 mm (1.1 in)
1959
19.8 mm (0.8 in)
1960
22.9 mm (0.9 in)
1961
55.9 mm (2.2 in)
1962
36.3 mm (1.4 in)
1963
36.8 mm (1.4 in)
1964
15.7 mm (0.6 in)
1965
24.6 mm (1.0 in)
1966
18.5 mm (0.7 in)
1967
32.5 mm (1.3 in)
1968
23.6 mm (0.9 in)
1969
24.6 mm (1.0 in)
1970
25.4 mm (1.0 in)
1971
43.2 mm (1.7 in)
1972
31.8 mm (1.3 in)
1973
49.3 mm (1.9 in)
1974
20.3 mm (0.8 in)
1975
43.2 mm (1.7 in)
1976
66.8 mm (2.6 in)
1977
57.2 mm (2.3 in)
1978
34.3 mm (1.4 in)
1979
20.3 mm (0.8 in)
1980
22.9 mm (0.9 in)
1981
29.2 mm (1.1 in)
1982
33.5 mm (1.3 in)
1983
21.6 mm (0.9 in)
1984
27.9 mm (1.1 in)
1985
49.0 mm (1.9 in)
1986
39.1 mm (1.5 in)
1987
22.6 mm (0.9 in)
1988
12.4 mm (0.5 in)
1989
26.4 mm (1.0 in)
1990
21.8 mm (0.9 in)
1991
47.0 mm (1.9 in)
1992
61.7 mm (2.4 in)
1993
52.8 mm (2.1 in)
1994
16.3 mm (0.6 in)
1995
27.4 mm (1.1 in)
1996
14.0 mm (0.6 in)
1997
22.1 mm (0.9 in)
1998
31.2 mm (1.2 in)
1999
31.5 mm (1.2 in)
2000
13.0 mm (0.5 in)
2001
31.5 mm (1.2 in)
2002
18.5 mm (0.7 in)
2003
18.5 mm (0.7 in)
2004
14.2 mm (0.6 in)
2005
60.5 mm (2.4 in)
2006
14.5 mm (0.6 in)
2007
32.8 mm (1.3 in)
2008
40.6 mm (1.6 in)
2009
16.5 mm (0.6 in)
2010
42.7 mm (1.7 in)
2011
30.7 mm (1.2 in)
2012
14.7 mm (0.6 in)
2013
3.0 mm (0.12 in)
2014
37.1 mm (1.5 in)
2015
32.8 mm (1.3 in)
2016
77.2 mm (3.0 in)
2017
58.7 mm (2.3 in)
2018
46.7 mm (1.8 in)
2019
22.4 mm (0.9 in)
2020
19.8 mm (0.8 in)
2022
11.4 mm (0.4 in)
2023
61.0 mm (2.4 in)
2024
27.9 mm (1.1 in)
Wettest five days (Rx5day)
The wettest five days of the year at Diversion Dam, 1920 to 2024. The record is 106.4 mm (4.2 in) in 1924, marked on the chart; the median year is 39.9 mm (1.6 in).
Wettest five days (Rx5day) at Diversion Dam by year
Year
Wettest five days (Rx5day)
1920
n/a
1921
36.0 mm (1.4 in)
1922
51.3 mm (2.0 in)
1923
84.6 mm (3.3 in)
1924
106.4 mm (4.2 in)
1925
40.6 mm (1.6 in)
1926
16.3 mm (0.6 in)
1927
36.4 mm (1.4 in)
1928
47.0 mm (1.9 in)
1929
11.9 mm (0.5 in)
1930
70.9 mm (2.8 in)
1931
42.7 mm (1.7 in)
1932
31.8 mm (1.3 in)
1933
40.8 mm (1.6 in)
1934
25.2 mm (1.0 in)
1935
32.0 mm (1.3 in)
1936
45.5 mm (1.8 in)
1937
39.6 mm (1.6 in)
1938
34.3 mm (1.4 in)
1939
37.1 mm (1.5 in)
1940
58.2 mm (2.3 in)
1948
32.0 mm (1.3 in)
1949
49.0 mm (1.9 in)
1950
56.6 mm (2.2 in)
1951
32.0 mm (1.3 in)
1952
28.4 mm (1.1 in)
1953
26.0 mm (1.0 in)
1954
20.8 mm (0.8 in)
1955
37.0 mm (1.5 in)
1956
40.2 mm (1.6 in)
1957
95.8 mm (3.8 in)
1958
38.1 mm (1.5 in)
1959
37.9 mm (1.5 in)
1960
40.9 mm (1.6 in)
1961
68.3 mm (2.7 in)
1962
52.3 mm (2.1 in)
1963
72.9 mm (2.9 in)
1964
23.5 mm (0.9 in)
1965
25.6 mm (1.0 in)
1966
30.5 mm (1.2 in)
1967
88.4 mm (3.5 in)
1968
65.8 mm (2.6 in)
1969
55.9 mm (2.2 in)
1970
42.7 mm (1.7 in)
1971
71.2 mm (2.8 in)
1972
38.6 mm (1.5 in)
1973
85.6 mm (3.4 in)
1974
20.4 mm (0.8 in)
1975
49.3 mm (1.9 in)
1976
81.6 mm (3.2 in)
1977
73.7 mm (2.9 in)
1978
72.7 mm (2.9 in)
1979
31.8 mm (1.3 in)
1980
37.5 mm (1.5 in)
1981
52.6 mm (2.1 in)
1982
70.4 mm (2.8 in)
1983
28.0 mm (1.1 in)
1984
39.1 mm (1.5 in)
1985
49.0 mm (1.9 in)
1986
57.9 mm (2.3 in)
1987
32.5 mm (1.3 in)
1988
15.2 mm (0.6 in)
1989
66.3 mm (2.6 in)
1990
28.4 mm (1.1 in)
1991
47.0 mm (1.9 in)
1992
65.5 mm (2.6 in)
1993
72.7 mm (2.9 in)
1994
37.1 mm (1.5 in)
1995
46.7 mm (1.8 in)
1996
37.6 mm (1.5 in)
1997
29.7 mm (1.2 in)
1998
39.1 mm (1.5 in)
1999
47.2 mm (1.9 in)
2000
14.5 mm (0.6 in)
2001
35.1 mm (1.4 in)
2002
22.2 mm (0.9 in)
2003
32.3 mm (1.3 in)
2004
32.0 mm (1.3 in)
2005
71.5 mm (2.8 in)
2006
16.5 mm (0.6 in)
2007
32.8 mm (1.3 in)
2008
78.7 mm (3.1 in)
2009
37.1 mm (1.5 in)
2010
70.6 mm (2.8 in)
2011
48.8 mm (1.9 in)
2012
14.7 mm (0.6 in)
2013
3.0 mm (0.12 in)
2014
44.0 mm (1.7 in)
2015
64.1 mm (2.5 in)
2016
83.8 mm (3.3 in)
2017
81.0 mm (3.2 in)
2018
54.1 mm (2.1 in)
2019
38.1 mm (1.5 in)
2020
23.8 mm (0.9 in)
2022
20.3 mm (0.8 in)
2023
101.9 mm (4.0 in)
2024
27.9 mm (1.1 in)
Longest dry spell (CDD)
The longest dry spell of the year at Diversion Dam, 1920 to 2024. The record is 98 days in 1960, marked on the chart; the median year is 47 days.
Longest dry spell (CDD) at Diversion Dam by year
Year
Longest dry spell (CDD)
1920
2 days
1921
28 days
1922
9 days
1923
25 days
1924
42 days
1925
29 days
1926
32 days
1927
55 days
1928
18 days
1929
35 days
1930
2 days
1931
39 days
1932
59 days
1933
46 days
1934
54 days
1935
40 days
1936
33 days
1937
33 days
1938
51 days
1939
59 days
1940
31 days
1948
33 days
1949
40 days
1950
51 days
1951
43 days
1952
48 days
1953
46 days
1954
35 days
1955
48 days
1956
43 days
1957
89 days
1958
55 days
1959
48 days
1960
98 days
1961
33 days
1962
45 days
1963
57 days
1964
65 days
1965
55 days
1966
47 days
1967
43 days
1968
63 days
1969
68 days
1970
67 days
1971
93 days
1972
61 days
1973
47 days
1974
69 days
1975
59 days
1976
66 days
1977
55 days
1978
50 days
1979
57 days
1980
74 days
1981
76 days
1982
57 days
1983
44 days
1984
61 days
1985
51 days
1986
83 days
1987
38 days
1988
81 days
1989
60 days
1990
56 days
1991
50 days
1992
61 days
1993
34 days
1994
51 days
1995
60 days
1996
59 days
1997
39 days
1998
41 days
1999
76 days
2000
49 days
2001
53 days
2002
37 days
2003
29 days
2004
33 days
2005
36 days
2006
44 days
2007
48 days
2008
74 days
2009
43 days
2010
32 days
2011
52 days
2012
36 days
2013
17 days
2014
19 days
2015
35 days
2016
49 days
2017
29 days
2018
45 days
2019
87 days
2020
43 days
2022
21 days
2023
32 days
2024
20 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
68 years with a frost
Across 68 years with a frost, the median last spring frost at Diversion Dam falls on 27 May and the median first autumn frost on 17 September, which leaves a median of 112 days between them.
In 1970 to 2023 the median growing season was 109 days. That is 11 days fewer than in 1921 to 1959.
Fitted over all years, the growing season changes by -1.1 days per decade at this station.
Frost dates and growing season at Diversion Dam
Measure
Median, all years
Earliest period (1921 to 1959)
Recent period (1970 to 2023)
Recent against earliest
Fitted trend
Last spring frost
27 May
24 May
30 May
6 days later
+0.7 days per decade
First autumn frost
17 September
19 September
16 September
3 days earlier
-0.4 days per decade
Growing days
112 days
120 days
109 days
11 days fewer
-1.1 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
70 years, 1932 to 2023
A day with at least 28.2 mm (1.1 in) of rain is expected about once in 2 years. A day with at least 87.2 mm (3.4 in) of rain is expected about once in 100 years.
Rainfall return levels at Diversion Dam: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
28.2 mm (1.1 in)
5 years
41.0 mm (1.6 in)
10 years
50.5 mm (2.0 in)
25 years
64.0 mm (2.5 in)
50 years
75.1 mm (3.0 in)
100 years
87.2 mm (3.4 in)
Longer than the 70 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, 70 years of values from 1932 to 2023.
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: 77.2 mm (3.0 in) in 2016; 66.8 mm (2.6 in) in 1976; 61.7 mm (2.4 in) in 1992.
Station Changes
No change in the annual mean temperature of this station was found against its neighbours.
Download the Data
Data for Diversion Dam standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Diversion Dam 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.