Record envelope, standing records and threshold days for South Pass City (USC00488385), Wyoming, United States, with 115 years of record.
Key Facts for South Pass City
South Pass City (USC00488385) is a weather station in Wyoming, United States at 42.47 latitude and -108.80 longitude, 2,390 m (7,840 ft) above sea level.
The station reports from 1900 to 2014, 115 years of record.
1,464 records set at South Pass City still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
South Pass City set a daily record high minimum temperature of 5.6 C (42.1 F) on 16 October 2014.
About the Station
Location: Wyoming, United States, 42.47 latitude, -108.80 longitude.
Elevation: 2,390 m (7,840 ft).
Period of record: 1900 to 2014, 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 South Pass City. 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 South Pass City, 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)
-42.8 C (-45.0 F)
n/a
n/a
Feb
11.7 C (53.1 F)
-40.0 C (-40.0 F)
n/a
n/a
Mar
20.0 C (68.0 F)
-36.1 C (-33.0 F)
n/a
n/a
Apr
23.9 C (75.0 F)
-30.0 C (-22.0 F)
n/a
n/a
May
28.3 C (82.9 F)
-17.8 C (0.0 F)
n/a
n/a
Jun
33.9 C (93.0 F)
-14.4 C (6.1 F)
n/a
n/a
Jul
36.7 C (98.1 F)
-7.8 C (18.0 F)
n/a
n/a
Aug
38.9 C (102.0 F)
-12.8 C (9.0 F)
n/a
n/a
Sep
30.6 C (87.1 F)
-20.6 C (-5.1 F)
n/a
n/a
Oct
26.7 C (80.1 F)
-32.2 C (-26.0 F)
n/a
n/a
Nov
18.3 C (64.9 F)
-34.4 C (-29.9 F)
n/a
n/a
Dec
16.7 C (62.1 F)
-43.3 C (-45.9 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at South Pass City still stand. 1905 holds the most, with 39.
Standing records at South Pass City by the year they were set
Year set
Standing records
1900
25
1901
26
1902
13
1903
37
1904
26
1905
39
1906
25
1907
22
1909
11
1910
15
1911
16
1912
11
1913
35
1914
14
1915
17
1916
24
1917
28
1918
22
1919
22
1920
12
1921
15
1922
15
1923
10
1924
23
1925
11
1926
11
1927
16
1928
12
1929
13
1930
11
1931
21
1932
28
1933
19
1934
16
1935
16
1936
17
1937
19
1938
18
1939
14
1940
17
1941
10
1942
15
1943
22
1944
3
1945
25
1946
18
1947
14
1948
10
1949
10
1950
21
1951
10
1952
8
1953
6
1962
9
1963
23
1964
9
1965
12
1966
16
1967
11
1968
11
1969
22
1970
15
1971
14
1972
16
1974
2
1975
10
1976
14
1977
24
1978
25
1979
13
1980
4
1992
9
1993
10
1994
8
1995
13
1996
28
1997
6
1998
13
1999
16
2000
12
2001
9
2002
22
2003
32
2004
7
2005
5
2006
25
2007
28
2008
1
2009
8
2010
6
2011
5
2012
16
2014
1
All-Time Record Progression
6 new records
6 all-time records were set at South Pass City between 8 February 1933 and 3 January 1998. Each dot is a new record.
When South Pass City set new all-time records
Date
Kind
Detail
1933-02-08
Record low maximum temperature
Record low maximum temperature -23.9 C (-11.0 F)
1937-01-08
Record low maximum temperature
Record low maximum temperature -25.0 C (-13.0 F)
1949-08-08
Record high minimum temperature
Record high minimum temperature 19.4 C (66.9 F)
1952-05-16
Record daily precipitation
Record daily precipitation 50.8 mm (2.0 in)
1963-01-11
Record low maximum temperature
Record low maximum temperature -28.3 C (-18.9 F)
1998-01-03
Record daily precipitation
Record daily precipitation 57.9 mm (2.3 in)
Wettest Day of Each Month
Jan: 57.9 mm (2.3 in)
The wettest day on record for each calendar month at South Pass City. The most was 57.9 mm (2.3 in) on 3 January 1998.
Record daily precipitation for each month at South Pass City
Month
Record daily precipitation (mm)
Date
Jan
57.9 mm (2.3 in)
3 January 1998
Feb
45.7 mm (1.8 in)
25 February 1904
Mar
30.5 mm (1.2 in)
17 March 1907
Apr
34.8 mm (1.4 in)
21 April 1944
May
50.8 mm (2.0 in)
16 May 1952
Jun
37.8 mm (1.5 in)
11 June 1947
Jul
46.2 mm (1.8 in)
9 July 1926
Aug
32.8 mm (1.3 in)
26 August 1933
Sep
40.6 mm (1.6 in)
18 September 1978
Oct
38.1 mm (1.5 in)
20 October 1979
Nov
45.7 mm (1.8 in)
11 November 1903
Dec
36.6 mm (1.4 in)
22 December 1964
Period of Record Coverage
1900 to 2014
Complete yearUnder 90 percent of days
93 years of record at South Pass City, 1900 to 2014. 21 years have data for under 90 percent of days and are left out of rankings: 1900, 1902, 1903, 1905, 1907, 1909, 1952, 1953 and others.
Cooler than the station meanWarmer than the station mean
One stripe for each of 68 complete years at South Pass City, 1904 to 2010. Blue stripes are years cooler than the station's own mean of 1.4 C (34.6 F); red stripes are warmer. The coolest year was 1945, at 0.1 C (32.2 F), and the warmest was 2007, at 3.7 C (38.7 F). The strongest colour marks a difference of 2.3 C (4.1 F).
Annual mean temperature at South Pass City as warming stripes, 1904 to 2010
Year
Annual mean temperature
Difference from the station mean
1904
2.6 C
+1.17 C
1906
1.1 C
-0.36 C
1910
2.5 C
+1.05 C
1911
0.7 C
-0.79 C
1912
0.2 C
-1.24 C
1913
0.9 C
-0.51 C
1915
1.5 C
+0.01 C
1916
0.5 C
-0.92 C
1917
0.2 C
-1.21 C
1918
1.5 C
+0.01 C
1919
1.6 C
+0.13 C
1920
0.6 C
-0.84 C
1921
2.2 C
+0.75 C
1922
0.3 C
-1.19 C
1923
0.5 C
-0.98 C
1924
0.4 C
-1.02 C
1925
1.8 C
+0.32 C
1926
1.7 C
+0.28 C
1927
0.8 C
-0.65 C
1928
0.6 C
-0.82 C
1929
0.5 C
-0.90 C
1930
0.6 C
-0.81 C
1931
1.7 C
+0.26 C
1932
0.2 C
-1.21 C
1933
1.1 C
-0.34 C
1934
2.9 C
+1.42 C
1935
0.6 C
-0.88 C
1936
0.7 C
-0.78 C
1937
0.2 C
-1.21 C
1938
0.7 C
-0.74 C
1939
1.9 C
+0.43 C
1940
2.6 C
+1.14 C
1941
1.9 C
+0.48 C
1942
1.1 C
-0.32 C
1943
1.8 C
+0.39 C
1944
0.9 C
-0.52 C
1945
0.1 C
-1.35 C
1946
0.9 C
-0.58 C
1947
0.7 C
-0.70 C
1948
0.8 C
-0.66 C
1949
1.9 C
+0.45 C
1950
1.7 C
+0.25 C
1951
0.6 C
-0.85 C
1963
3.6 C
+2.11 C
1964
1.5 C
+0.10 C
1965
2.1 C
+0.69 C
1966
2.7 C
+1.25 C
1967
2.7 C
+1.28 C
1968
2.1 C
+0.70 C
1969
3.1 C
+1.67 C
1970
2.4 C
+0.96 C
1975
1.0 C
-0.48 C
1976
1.6 C
+0.17 C
1977
2.6 C
+1.15 C
1978
0.7 C
-0.76 C
1979
0.8 C
-0.62 C
1993
0.6 C
-0.89 C
1994
1.9 C
+0.45 C
1995
1.6 C
+0.18 C
1996
1.7 C
+0.26 C
1997
1.3 C
-0.19 C
1999
2.0 C
+0.56 C
2000
1.8 C
+0.34 C
2001
2.4 C
+0.94 C
2002
1.2 C
-0.23 C
2003
2.4 C
+1.00 C
2007
3.7 C
+2.28 C
2010
2.0 C
+0.59 C
The annual mean temperature here has risen by 0.11 C (0.05 to 0.18) per decade over 1904 to 2010. In Fahrenheit: 0.2 F (0.1 to 0.3) 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 South Pass City
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.11 C (0.05 to 0.18) per decade
0.2 F (0.1 to 0.3) per decade
1904 to 2010
68
Rise
Mean daily maximum
0.1 C (0.1 to 0.2) per decade
0.3 F (0.1 to 0.4) per decade
1904 to 2010
68
Rise
Mean daily minimum
0.08 C (-0.01 to 0.17) per decade
0.15 F (-0.02 to 0.31) per decade
1904 to 2010
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
1900 to 2014
Yearly extremes at South Pass City: 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)
1903
29.4 C (84.9 F)
93
Coldest night (TNn)
-43.3 C (-45.9 F)
1924
-32.8 C (-27.0 F)
93
Wettest day (Rx1day)
57.9 mm (2.3 in)
1998
24.9 mm (1.0 in)
103
Wettest five days (Rx5day)
87.1 mm (3.4 in)
1972
37.8 mm (1.5 in)
103
Longest dry spell (CDD)
79 days
1928
30 days
103
Hottest day (TXx)
The hottest day of the year at South Pass City, 1900 to 2014. The record is 38.9 C (102.0 F) in 1903, marked on the chart; the median year is 29.4 C (84.9 F).
Hottest day (TXx) at South Pass City by year
Year
Hottest day (TXx)
1900
32.8 C (91.0 F)
1901
36.7 C (98.1 F)
1902
30.0 C (86.0 F)
1903
38.9 C (102.0 F)
1904
31.1 C (88.0 F)
1905
31.7 C (89.1 F)
1906
35.0 C (95.0 F)
1907
29.4 C (84.9 F)
1909
28.9 C (84.0 F)
1910
28.3 C (82.9 F)
1911
33.9 C (93.0 F)
1912
26.7 C (80.1 F)
1913
27.8 C (82.0 F)
1914
27.2 C (81.0 F)
1915
26.7 C (80.1 F)
1916
28.3 C (82.9 F)
1917
28.9 C (84.0 F)
1918
30.6 C (87.1 F)
1919
30.6 C (87.1 F)
1920
29.4 C (84.9 F)
1921
30.0 C (86.0 F)
1922
28.9 C (84.0 F)
1923
30.0 C (86.0 F)
1924
29.4 C (84.9 F)
1925
32.2 C (90.0 F)
1926
30.6 C (87.1 F)
1927
29.4 C (84.9 F)
1928
28.9 C (84.0 F)
1929
30.6 C (87.1 F)
1930
29.4 C (84.9 F)
1931
32.8 C (91.0 F)
1932
28.3 C (82.9 F)
1933
30.0 C (86.0 F)
1934
30.6 C (87.1 F)
1935
30.6 C (87.1 F)
1936
29.4 C (84.9 F)
1937
28.9 C (84.0 F)
1938
28.9 C (84.0 F)
1939
36.1 C (97.0 F)
1940
32.2 C (90.0 F)
1941
30.0 C (86.0 F)
1942
30.0 C (86.0 F)
1943
30.0 C (86.0 F)
1944
26.7 C (80.1 F)
1945
28.3 C (82.9 F)
1946
27.8 C (82.0 F)
1947
27.2 C (81.0 F)
1948
28.3 C (82.9 F)
1949
29.4 C (84.9 F)
1950
28.9 C (84.0 F)
1951
30.0 C (86.0 F)
1952
28.3 C (82.9 F)
1953
29.4 C (84.9 F)
1954
n/a
1955
n/a
1956
n/a
1957
n/a
1958
n/a
1959
n/a
1960
n/a
1961
n/a
1962
29.4 C (84.9 F)
1963
28.3 C (82.9 F)
1964
28.9 C (84.0 F)
1965
28.9 C (84.0 F)
1966
30.0 C (86.0 F)
1967
28.3 C (82.9 F)
1968
30.6 C (87.1 F)
1969
30.0 C (86.0 F)
1970
31.7 C (89.1 F)
1971
30.0 C (86.0 F)
1972
28.9 C (84.0 F)
1973
n/a
1974
28.3 C (82.9 F)
1975
28.9 C (84.0 F)
1976
31.1 C (88.0 F)
1977
30.6 C (87.1 F)
1978
29.4 C (84.9 F)
1979
30.6 C (87.1 F)
1980
23.3 C (73.9 F)
1991
n/a
1992
28.9 C (84.0 F)
1993
27.2 C (81.0 F)
1994
30.6 C (87.1 F)
1995
29.4 C (84.9 F)
1996
30.6 C (87.1 F)
1997
29.4 C (84.9 F)
1998
31.7 C (89.1 F)
1999
28.9 C (84.0 F)
2000
31.1 C (88.0 F)
2001
31.7 C (89.1 F)
2002
32.2 C (90.0 F)
2003
31.7 C (89.1 F)
2004
28.3 C (82.9 F)
2005
12.8 C (55.0 F)
2006
32.8 C (91.0 F)
2007
32.2 C (90.0 F)
2008
6.1 C (43.0 F)
2009
30.0 C (86.0 F)
2010
30.0 C (86.0 F)
2011
29.4 C (84.9 F)
2012
30.6 C (87.1 F)
2014
18.9 C (66.0 F)
Coldest night (TNn)
The coldest night of the year at South Pass City, 1900 to 2014. The record is -43.3 C (-45.9 F) in 1924, marked on the chart; the median year is -32.8 C (-27.0 F).
Coldest night (TNn) at South Pass City by year
Year
Coldest night (TNn)
1900
-27.2 C (-17.0 F)
1901
-30.0 C (-22.0 F)
1902
-31.7 C (-25.1 F)
1903
-37.8 C (-36.0 F)
1904
-35.0 C (-31.0 F)
1905
-40.0 C (-40.0 F)
1906
-36.1 C (-33.0 F)
1907
-25.0 C (-13.0 F)
1909
-34.4 C (-29.9 F)
1910
-35.0 C (-31.0 F)
1911
-36.1 C (-33.0 F)
1912
-31.7 C (-25.1 F)
1913
-39.4 C (-38.9 F)
1914
-32.2 C (-26.0 F)
1915
-36.1 C (-33.0 F)
1916
-38.3 C (-36.9 F)
1917
-39.4 C (-38.9 F)
1918
-37.2 C (-35.0 F)
1919
-35.6 C (-32.1 F)
1920
-30.0 C (-22.0 F)
1921
-30.6 C (-23.1 F)
1922
-42.8 C (-45.0 F)
1923
-37.8 C (-36.0 F)
1924
-43.3 C (-45.9 F)
1925
-28.9 C (-20.0 F)
1926
-33.3 C (-27.9 F)
1927
-35.6 C (-32.1 F)
1928
-32.2 C (-26.0 F)
1929
-37.2 C (-35.0 F)
1930
-40.0 C (-40.0 F)
1931
-32.8 C (-27.0 F)
1932
-35.6 C (-32.1 F)
1933
-38.9 C (-38.0 F)
1934
-28.3 C (-18.9 F)
1935
-37.8 C (-36.0 F)
1936
-37.8 C (-36.0 F)
1937
-38.9 C (-38.0 F)
1938
-33.9 C (-29.0 F)
1939
-36.7 C (-34.1 F)
1940
-35.0 C (-31.0 F)
1941
-31.1 C (-24.0 F)
1942
-37.2 C (-35.0 F)
1943
-36.7 C (-34.1 F)
1944
-31.1 C (-24.0 F)
1945
-30.0 C (-22.0 F)
1946
-31.1 C (-24.0 F)
1947
-31.1 C (-24.0 F)
1948
-37.8 C (-36.0 F)
1949
-33.3 C (-27.9 F)
1950
-31.7 C (-25.1 F)
1951
-36.1 C (-33.0 F)
1952
-33.3 C (-27.9 F)
1953
-12.8 C (9.0 F)
1954
n/a
1955
n/a
1956
n/a
1957
n/a
1958
n/a
1959
n/a
1960
n/a
1961
n/a
1962
-28.3 C (-18.9 F)
1963
-36.1 C (-33.0 F)
1964
-35.0 C (-31.0 F)
1965
-30.6 C (-23.1 F)
1966
-29.4 C (-20.9 F)
1967
-25.6 C (-14.1 F)
1968
-28.9 C (-20.0 F)
1969
-27.8 C (-18.0 F)
1970
-30.0 C (-22.0 F)
1971
-32.8 C (-27.0 F)
1972
-31.7 C (-25.1 F)
1973
n/a
1974
-30.0 C (-22.0 F)
1975
-31.7 C (-25.1 F)
1976
-31.7 C (-25.1 F)
1977
-33.9 C (-29.0 F)
1978
-34.4 C (-29.9 F)
1979
-40.0 C (-40.0 F)
1980
-36.7 C (-34.1 F)
1991
n/a
1992
-32.8 C (-27.0 F)
1993
-30.6 C (-23.1 F)
1994
-28.3 C (-18.9 F)
1995
-28.9 C (-20.0 F)
1996
-36.7 C (-34.1 F)
1997
-28.3 C (-18.9 F)
1998
-32.8 C (-27.0 F)
1999
-30.0 C (-22.0 F)
2000
-28.9 C (-20.0 F)
2001
-31.1 C (-24.0 F)
2002
-34.4 C (-29.9 F)
2003
-35.0 C (-31.0 F)
2004
-33.3 C (-27.9 F)
2005
-31.1 C (-24.0 F)
2006
-31.7 C (-25.1 F)
2007
-31.7 C (-25.1 F)
2008
-23.9 C (-11.0 F)
2009
-33.9 C (-29.0 F)
2010
-32.2 C (-26.0 F)
2011
-36.1 C (-33.0 F)
2012
-26.7 C (-16.1 F)
2014
-7.2 C (19.0 F)
Wettest day (Rx1day)
The wettest day of the year at South Pass City, 1900 to 2014. The record is 57.9 mm (2.3 in) in 1998, marked on the chart; the median year is 24.9 mm (1.0 in).
Wettest day (Rx1day) at South Pass City by year
Year
Wettest day (Rx1day)
1900
15.2 mm (0.6 in)
1901
30.5 mm (1.2 in)
1902
23.9 mm (0.9 in)
1903
45.7 mm (1.8 in)
1904
45.7 mm (1.8 in)
1905
35.6 mm (1.4 in)
1906
29.2 mm (1.1 in)
1907
30.5 mm (1.2 in)
1909
37.8 mm (1.5 in)
1910
20.3 mm (0.8 in)
1911
30.5 mm (1.2 in)
1912
23.1 mm (0.9 in)
1913
9.4 mm (0.37 in)
1914
17.3 mm (0.7 in)
1915
26.7 mm (1.1 in)
1916
12.7 mm (0.5 in)
1917
13.5 mm (0.5 in)
1918
15.7 mm (0.6 in)
1919
20.6 mm (0.8 in)
1920
20.3 mm (0.8 in)
1921
24.9 mm (1.0 in)
1922
20.6 mm (0.8 in)
1923
33.5 mm (1.3 in)
1924
17.5 mm (0.7 in)
1925
19.1 mm (0.8 in)
1926
46.2 mm (1.8 in)
1927
25.7 mm (1.0 in)
1928
20.6 mm (0.8 in)
1929
24.4 mm (1.0 in)
1930
27.4 mm (1.1 in)
1931
22.9 mm (0.9 in)
1932
32.3 mm (1.3 in)
1933
32.8 mm (1.3 in)
1934
27.4 mm (1.1 in)
1935
19.1 mm (0.8 in)
1936
24.1 mm (0.9 in)
1937
27.4 mm (1.1 in)
1938
16.3 mm (0.6 in)
1939
18.5 mm (0.7 in)
1940
22.4 mm (0.9 in)
1941
27.7 mm (1.1 in)
1942
27.7 mm (1.1 in)
1943
25.9 mm (1.0 in)
1944
34.8 mm (1.4 in)
1945
34.8 mm (1.4 in)
1946
20.6 mm (0.8 in)
1947
37.8 mm (1.5 in)
1948
21.1 mm (0.8 in)
1949
18.0 mm (0.7 in)
1950
33.0 mm (1.3 in)
1951
24.1 mm (0.9 in)
1952
50.8 mm (2.0 in)
1953
14.7 mm (0.6 in)
1954
12.2 mm (0.5 in)
1955
17.8 mm (0.7 in)
1956
26.7 mm (1.1 in)
1957
25.4 mm (1.0 in)
1958
20.3 mm (0.8 in)
1959
17.0 mm (0.7 in)
1960
26.7 mm (1.1 in)
1961
15.0 mm (0.6 in)
1962
20.6 mm (0.8 in)
1963
34.5 mm (1.4 in)
1964
36.6 mm (1.4 in)
1965
22.4 mm (0.9 in)
1966
17.8 mm (0.7 in)
1967
23.4 mm (0.9 in)
1968
13.2 mm (0.5 in)
1969
29.0 mm (1.1 in)
1970
17.0 mm (0.7 in)
1971
25.7 mm (1.0 in)
1972
29.7 mm (1.2 in)
1973
8.1 mm (0.32 in)
1974
13.5 mm (0.5 in)
1975
22.1 mm (0.9 in)
1976
35.8 mm (1.4 in)
1977
24.9 mm (1.0 in)
1978
40.6 mm (1.6 in)
1979
38.1 mm (1.5 in)
1980
26.9 mm (1.1 in)
1991
28.7 mm (1.1 in)
1992
19.3 mm (0.8 in)
1993
30.5 mm (1.2 in)
1994
25.4 mm (1.0 in)
1995
27.9 mm (1.1 in)
1996
27.4 mm (1.1 in)
1997
36.3 mm (1.4 in)
1998
57.9 mm (2.3 in)
1999
27.2 mm (1.1 in)
2000
32.3 mm (1.3 in)
2001
17.8 mm (0.7 in)
2002
15.7 mm (0.6 in)
2003
17.8 mm (0.7 in)
2004
33.0 mm (1.3 in)
2005
13.2 mm (0.5 in)
2006
24.9 mm (1.0 in)
2007
23.6 mm (0.9 in)
2008
10.4 mm (0.4 in)
2009
38.1 mm (1.5 in)
2010
38.1 mm (1.5 in)
2011
41.9 mm (1.6 in)
2012
12.7 mm (0.5 in)
2014
0.0 mm (0.00 in)
Wettest five days (Rx5day)
The wettest five days of the year at South Pass City, 1900 to 2014. The record is 87.1 mm (3.4 in) in 1972, marked on the chart; the median year is 37.8 mm (1.5 in).
Wettest five days (Rx5day) at South Pass City by year
Year
Wettest five days (Rx5day)
1900
34.3 mm (1.4 in)
1901
43.2 mm (1.7 in)
1902
23.9 mm (0.9 in)
1903
68.5 mm (2.7 in)
1904
66.0 mm (2.6 in)
1905
35.6 mm (1.4 in)
1906
47.5 mm (1.9 in)
1907
68.6 mm (2.7 in)
1909
47.9 mm (1.9 in)
1910
49.1 mm (1.9 in)
1911
60.5 mm (2.4 in)
1912
26.6 mm (1.0 in)
1913
16.3 mm (0.6 in)
1914
25.4 mm (1.0 in)
1915
43.8 mm (1.7 in)
1916
20.0 mm (0.8 in)
1917
36.9 mm (1.5 in)
1918
31.6 mm (1.2 in)
1919
28.0 mm (1.1 in)
1920
33.8 mm (1.3 in)
1921
42.0 mm (1.7 in)
1922
28.9 mm (1.1 in)
1923
39.1 mm (1.5 in)
1924
26.9 mm (1.1 in)
1925
36.2 mm (1.4 in)
1926
86.5 mm (3.4 in)
1927
35.4 mm (1.4 in)
1928
37.8 mm (1.5 in)
1929
40.9 mm (1.6 in)
1930
43.9 mm (1.7 in)
1931
32.8 mm (1.3 in)
1932
44.3 mm (1.7 in)
1933
37.9 mm (1.5 in)
1934
27.7 mm (1.1 in)
1935
23.1 mm (0.9 in)
1936
48.8 mm (1.9 in)
1937
53.6 mm (2.1 in)
1938
28.3 mm (1.1 in)
1939
19.0 mm (0.7 in)
1940
26.7 mm (1.1 in)
1941
46.2 mm (1.8 in)
1942
55.9 mm (2.2 in)
1943
48.3 mm (1.9 in)
1944
45.3 mm (1.8 in)
1945
65.6 mm (2.6 in)
1946
27.2 mm (1.1 in)
1947
69.1 mm (2.7 in)
1948
41.9 mm (1.6 in)
1949
47.5 mm (1.9 in)
1950
44.2 mm (1.7 in)
1951
37.3 mm (1.5 in)
1952
53.1 mm (2.1 in)
1953
22.3 mm (0.9 in)
1954
21.9 mm (0.9 in)
1955
46.2 mm (1.8 in)
1956
37.1 mm (1.5 in)
1957
44.2 mm (1.7 in)
1958
20.3 mm (0.8 in)
1959
27.7 mm (1.1 in)
1960
34.1 mm (1.3 in)
1961
29.5 mm (1.2 in)
1962
36.4 mm (1.4 in)
1963
56.4 mm (2.2 in)
1964
71.1 mm (2.8 in)
1965
31.8 mm (1.3 in)
1966
30.7 mm (1.2 in)
1967
35.6 mm (1.4 in)
1968
32.0 mm (1.3 in)
1969
62.0 mm (2.4 in)
1970
31.0 mm (1.2 in)
1971
74.5 mm (2.9 in)
1972
87.1 mm (3.4 in)
1973
8.9 mm (0.35 in)
1974
13.5 mm (0.5 in)
1975
37.3 mm (1.5 in)
1976
42.1 mm (1.7 in)
1977
42.2 mm (1.7 in)
1978
42.1 mm (1.7 in)
1979
51.5 mm (2.0 in)
1980
69.4 mm (2.7 in)
1991
33.5 mm (1.3 in)
1992
21.8 mm (0.9 in)
1993
71.0 mm (2.8 in)
1994
45.7 mm (1.8 in)
1995
37.8 mm (1.5 in)
1996
52.8 mm (2.1 in)
1997
51.3 mm (2.0 in)
1998
57.9 mm (2.3 in)
1999
63.7 mm (2.5 in)
2000
33.3 mm (1.3 in)
2001
22.4 mm (0.9 in)
2002
25.9 mm (1.0 in)
2003
32.8 mm (1.3 in)
2004
38.3 mm (1.5 in)
2005
13.5 mm (0.5 in)
2006
24.9 mm (1.0 in)
2007
40.1 mm (1.6 in)
2008
12.2 mm (0.5 in)
2009
41.9 mm (1.6 in)
2010
49.5 mm (1.9 in)
2011
63.9 mm (2.5 in)
2012
28.4 mm (1.1 in)
2014
0.0 mm (0.00 in)
Longest dry spell (CDD)
The longest dry spell of the year at South Pass City, 1900 to 2014. The record is 79 days in 1928, marked on the chart; the median year is 30 days.
Longest dry spell (CDD) at South Pass City by year
Year
Longest dry spell (CDD)
1900
33 days
1901
23 days
1902
31 days
1903
35 days
1904
43 days
1905
43 days
1906
21 days
1907
36 days
1909
35 days
1910
34 days
1911
27 days
1912
29 days
1913
34 days
1914
69 days
1915
33 days
1916
25 days
1917
37 days
1918
25 days
1919
39 days
1920
49 days
1921
44 days
1922
60 days
1923
18 days
1924
37 days
1925
19 days
1926
23 days
1927
26 days
1928
79 days
1929
61 days
1930
38 days
1931
41 days
1932
37 days
1933
45 days
1934
36 days
1935
32 days
1936
27 days
1937
26 days
1938
23 days
1939
58 days
1940
46 days
1941
24 days
1942
25 days
1943
23 days
1944
31 days
1945
24 days
1946
27 days
1947
40 days
1948
26 days
1949
16 days
1950
48 days
1951
26 days
1952
77 days
1953
32 days
1954
30 days
1955
28 days
1956
35 days
1957
17 days
1958
52 days
1959
29 days
1960
41 days
1961
33 days
1962
39 days
1963
29 days
1964
34 days
1965
25 days
1966
20 days
1967
18 days
1968
15 days
1969
32 days
1970
21 days
1971
19 days
1972
22 days
1973
20 days
1974
21 days
1975
29 days
1976
35 days
1977
49 days
1978
40 days
1979
57 days
1980
23 days
1991
23 days
1992
45 days
1993
19 days
1994
19 days
1995
19 days
1996
28 days
1997
20 days
1998
27 days
1999
24 days
2000
31 days
2001
22 days
2002
31 days
2003
35 days
2004
32 days
2005
14 days
2006
29 days
2007
39 days
2008
8 days
2009
30 days
2010
37 days
2011
41 days
2012
25 days
2014
5 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 South Pass City falls on 28 June and the median first autumn frost on 3 July, which leaves a median of 6 days between them.
In 1947 to 2010 the median growing season was 16 days. That is 10 days more than in 1904 to 1938.
Fitted over all years, the growing season changes by +2.2 days per decade at this station.
Frost dates and growing season at South Pass City
Measure
Median, all years
Earliest period (1904 to 1938)
Recent period (1947 to 2010)
Recent against earliest
Fitted trend
Last spring frost
28 June
28 June
27 June
1 day earlier
-0.1 days per decade
First autumn frost
3 July
2 July
7 July
5 days later
+2.1 days per decade
Growing days
6 days
6 days
16 days
10 days more
+2.2 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
80 years, 1903 to 2011
A day with at least 24.4 mm (1.0 in) of rain is expected about once in 2 years. A day with at least 51.1 mm (2.0 in) of rain is expected about once in 100 years.
Rainfall return levels at South Pass City: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
24.4 mm (1.0 in)
5 years
32.0 mm (1.3 in)
10 years
36.9 mm (1.5 in)
25 years
42.8 mm (1.7 in)
50 years
47.0 mm (1.9 in)
100 years
51.1 mm (2.0 in)
Longer than the 80 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, 80 years of values from 1903 to 2011.
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: 50.8 mm (2.0 in) in 1952; 46.2 mm (1.8 in) in 1926; 45.7 mm (1.8 in) in 1903.
Station Changes
3 suspected
3 changes were suspected in the annual mean temperature of South Pass City, at 1930, 1949 and 1978. Each is measured against neighbouring stations.
Relative to 5 neighbouring stations, the station's annual mean temperature from 1930 ran 0.5 C (0.8 F) lower than in the years before (possible change).
Relative to 5 neighbouring stations, the station's annual mean temperature from 1949 ran 0.9 C (1.7 F) higher than in the years before (likely change).
Relative to 5 neighbouring stations, the station's annual mean temperature from 1978 ran 1.2 C (2.1 F) lower than in the years before (likely change).
Suspected changes in the annual mean temperature at South Pass City, against neighbouring stations
Year
Shift (C)
Shift (F)
Strength
Neighbours
1930
-0.5
-0.8
possible
5
1949
+0.9
+1.7
likely
5
1978
-1.2
-2.1
likely
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 South Pass City standing records by year: CSV or JSON. Field meanings are on the data page.
Data for South Pass City 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 2026-10-12 (12 October 2026). Records are computed by this site and are not official.