Record envelope, standing records and threshold days for Denver WSO City (USW00093002), Colorado, United States, with 54 years of record.
Key Facts for Denver WSO City
Denver WSO City (USW00093002) is a weather station in Colorado, United States at 39.75 latitude and -104.98 longitude, 1,623 m (5,325 ft) above sea level.
The station reports from 1921 to 1974, 54 years of record.
1,464 records set at Denver WSO City still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Denver WSO City set a daily record high minimum temperature of 10.0 C (50.0 F) on 30 March 1974.
About the Station
Location: Colorado, United States, 39.75 latitude, -104.98 longitude.
Elevation: 1,623 m (5,325 ft).
Period of record: 1921 to 1974, 54 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 Denver WSO 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 Denver WSO City, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
22.2 C (72.0 F)
-28.9 C (-20.0 F)
n/a
n/a
Feb
23.9 C (75.0 F)
-31.7 C (-25.1 F)
n/a
n/a
Mar
27.2 C (81.0 F)
-21.7 C (-7.1 F)
n/a
n/a
Apr
29.4 C (84.9 F)
-12.2 C (10.0 F)
n/a
n/a
May
35.0 C (95.0 F)
-5.0 C (23.0 F)
n/a
n/a
Jun
37.8 C (100.0 F)
-0.6 C (30.9 F)
n/a
n/a
Jul
38.9 C (102.0 F)
6.7 C (44.1 F)
n/a
n/a
Aug
37.8 C (100.0 F)
7.8 C (46.0 F)
n/a
n/a
Sep
35.6 C (96.1 F)
-3.9 C (25.0 F)
n/a
n/a
Oct
30.6 C (87.1 F)
-13.3 C (8.1 F)
n/a
n/a
Nov
26.1 C (79.0 F)
-17.8 C (0.0 F)
n/a
n/a
Dec
26.1 C (79.0 F)
-26.1 C (-15.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Denver WSO City still stand. 1954 holds the most, with 46.
Standing records at Denver WSO City by the year they were set
Year set
Standing records
1921
21
1922
21
1923
19
1924
36
1925
30
1926
21
1927
31
1928
26
1929
33
1930
32
1931
40
1932
37
1933
35
1934
30
1935
21
1936
44
1937
27
1938
22
1939
32
1940
22
1941
16
1942
18
1943
28
1944
18
1945
28
1946
36
1947
32
1948
11
1949
16
1950
44
1951
41
1952
34
1953
23
1954
46
1955
28
1956
25
1957
20
1958
23
1959
36
1960
32
1961
12
1962
32
1963
33
1964
20
1965
23
1966
25
1967
15
1968
12
1969
33
1970
23
1971
29
1972
44
1973
16
1974
12
All-Time Record Progression
2 new records
2 all-time records were set at Denver WSO City between 24 June 1954 and 31 July 1966. Each dot is a new record.
When Denver WSO City set new all-time records
Date
Kind
Detail
1954-06-24
Record high minimum temperature
Record high minimum temperature 23.3 C (73.9 F)
1966-07-31
Record high minimum temperature
Record high minimum temperature 24.4 C (75.9 F)
Wettest Day of Each Month
Aug: 74.4 mm (2.9 in)
The wettest day on record for each calendar month at Denver WSO City. The most was 74.4 mm (2.9 in) on 23 August 1921.
Record daily precipitation for each month at Denver WSO City
Month
Record daily precipitation (mm)
Date
Jan
17.8 mm (0.7 in)
21 January 1974
Feb
18.0 mm (0.7 in)
10 February 1934
Mar
35.1 mm (1.4 in)
21 March 1944
Apr
54.9 mm (2.2 in)
24 April 1935
May
60.2 mm (2.4 in)
7 May 1969
Jun
56.6 mm (2.2 in)
16 June 1950
Jul
50.3 mm (2.0 in)
29 July 1956
Aug
74.4 mm (2.9 in)
23 August 1921
Sep
45.0 mm (1.8 in)
28 September 1936
Oct
39.4 mm (1.6 in)
3 October 1969
Nov
22.4 mm (0.9 in)
2 November 1946
Dec
26.7 mm (1.1 in)
23 December 1973
Period of Record Coverage
1921 to 1974
Complete yearUnder 90 percent of days
54 years of record at Denver WSO City, 1921 to 1974. 2 years have data for under 90 percent of days and are left out of rankings: 1948, 1974.
Cooler than the station meanWarmer than the station mean
One stripe for each of 52 complete years at Denver WSO City, 1921 to 1973. Blue stripes are years cooler than the station's own mean of 10.9 C (51.6 F); red stripes are warmer. The coolest year was 1929, at 9.3 C (48.7 F), and the warmest was 1954, at 12.8 C (55.1 F). The strongest colour marks a difference of 2.0 C (3.6 F).
Annual mean temperature at Denver WSO City as warming stripes, 1921 to 1973
Year
Annual mean temperature
Difference from the station mean
1921
11.3 C
+0.40 C
1922
10.5 C
-0.46 C
1923
9.4 C
-1.55 C
1924
9.7 C
-1.26 C
1925
10.9 C
+0.03 C
1926
10.6 C
-0.35 C
1927
10.3 C
-0.62 C
1928
10.1 C
-0.81 C
1929
9.3 C
-1.63 C
1930
10.4 C
-0.56 C
1931
11.3 C
+0.42 C
1932
10.4 C
-0.56 C
1933
12.0 C
+1.05 C
1934
12.7 C
+1.76 C
1935
11.0 C
+0.06 C
1936
11.2 C
+0.29 C
1937
10.3 C
-0.64 C
1938
11.2 C
+0.33 C
1939
11.6 C
+0.69 C
1940
11.0 C
+0.10 C
1941
10.8 C
-0.07 C
1942
10.1 C
-0.78 C
1943
11.4 C
+0.51 C
1944
10.4 C
-0.51 C
1945
10.5 C
-0.46 C
1946
11.5 C
+0.60 C
1947
10.5 C
-0.45 C
1949
10.7 C
-0.18 C
1950
11.0 C
+0.09 C
1951
9.8 C
-1.10 C
1952
11.3 C
+0.36 C
1953
11.9 C
+0.97 C
1954
12.8 C
+1.91 C
1955
10.9 C
-0.04 C
1956
11.7 C
+0.78 C
1957
10.9 C
-0.06 C
1958
11.5 C
+0.63 C
1959
10.8 C
-0.16 C
1960
11.0 C
+0.06 C
1961
10.5 C
-0.42 C
1962
11.4 C
+0.47 C
1963
12.2 C
+1.25 C
1964
10.9 C
-0.02 C
1965
10.9 C
-0.06 C
1966
11.5 C
+0.57 C
1967
10.9 C
-0.04 C
1968
10.7 C
-0.23 C
1969
10.9 C
+0.01 C
1970
10.9 C
0.00 C
1971
10.8 C
-0.16 C
1972
10.9 C
+0.01 C
1973
10.8 C
-0.07 C
The fitted trend in annual mean temperature here over 1921 to 1973 is 0.12 C (0.00 to 0.25) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: 0.22 F (-0.01 to 0.44) per decade. The slope is a straight line fitted to 52 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Denver WSO City
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.12 C (0.00 to 0.25) per decade
0.22 F (-0.01 to 0.44) per decade
1921 to 1973
52
Not clearly different from zero
Mean daily maximum
0.1 C (-0.1 to 0.2) per decade
0.1 F (-0.1 to 0.4) per decade
1921 to 1973
52
Not clearly different from zero
Mean daily minimum
0.2 C (0.1 to 0.3) per decade
0.3 F (0.1 to 0.5) per decade
1921 to 1973
52
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
1921 to 1974
Yearly extremes at Denver WSO 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)
1939
36.1 C (97.0 F)
54
Coldest night (TNn)
-31.7 C (-25.1 F)
1936
-20.6 C (-5.1 F)
54
Wettest day (Rx1day)
74.4 mm (2.9 in)
1921
31.8 mm (1.3 in)
54
Wettest five days (Rx5day)
119.7 mm (4.7 in)
1969
48.9 mm (1.9 in)
54
Longest dry spell (CDD)
89 days
1944
31 days
54
Hottest day (TXx)
The hottest day of the year at Denver WSO City, 1921 to 1974. The record is 38.9 C (102.0 F) in 1939, marked on the chart; the median year is 36.1 C (97.0 F).
Hottest day (TXx) at Denver WSO City by year
Year
Hottest day (TXx)
1921
36.1 C (97.0 F)
1922
36.7 C (98.1 F)
1923
34.4 C (93.9 F)
1924
36.7 C (98.1 F)
1925
37.2 C (99.0 F)
1926
36.1 C (97.0 F)
1927
35.0 C (95.0 F)
1928
35.6 C (96.1 F)
1929
35.0 C (95.0 F)
1930
35.6 C (96.1 F)
1931
37.8 C (100.0 F)
1932
36.1 C (97.0 F)
1933
36.1 C (97.0 F)
1934
37.8 C (100.0 F)
1935
36.1 C (97.0 F)
1936
37.8 C (100.0 F)
1937
36.1 C (97.0 F)
1938
37.8 C (100.0 F)
1939
38.9 C (102.0 F)
1940
37.2 C (99.0 F)
1941
33.9 C (93.0 F)
1942
35.0 C (95.0 F)
1943
35.6 C (96.1 F)
1944
35.6 C (96.1 F)
1945
35.0 C (95.0 F)
1946
35.6 C (96.1 F)
1947
36.1 C (97.0 F)
1948
34.4 C (93.9 F)
1949
34.4 C (93.9 F)
1950
34.4 C (93.9 F)
1951
35.6 C (96.1 F)
1952
36.7 C (98.1 F)
1953
37.8 C (100.0 F)
1954
38.3 C (100.9 F)
1955
35.6 C (96.1 F)
1956
35.0 C (95.0 F)
1957
36.1 C (97.0 F)
1958
35.0 C (95.0 F)
1959
35.6 C (96.1 F)
1960
36.1 C (97.0 F)
1961
35.0 C (95.0 F)
1962
36.1 C (97.0 F)
1963
36.7 C (98.1 F)
1964
36.7 C (98.1 F)
1965
34.4 C (93.9 F)
1966
36.1 C (97.0 F)
1967
33.9 C (93.0 F)
1968
36.1 C (97.0 F)
1969
37.2 C (99.0 F)
1970
36.7 C (98.1 F)
1971
37.8 C (100.0 F)
1972
36.7 C (98.1 F)
1973
38.9 C (102.0 F)
1974
23.9 C (75.0 F)
Coldest night (TNn)
The coldest night of the year at Denver WSO City, 1921 to 1974. The record is -31.7 C (-25.1 F) in 1936, marked on the chart; the median year is -20.6 C (-5.1 F).
Coldest night (TNn) at Denver WSO City by year
Year
Coldest night (TNn)
1921
-17.2 C (1.0 F)
1922
-23.3 C (-9.9 F)
1923
-25.0 C (-13.0 F)
1924
-26.1 C (-15.0 F)
1925
-17.2 C (1.0 F)
1926
-23.9 C (-11.0 F)
1927
-24.4 C (-11.9 F)
1928
-23.3 C (-9.9 F)
1929
-22.8 C (-9.0 F)
1930
-28.9 C (-20.0 F)
1931
-18.9 C (-2.0 F)
1932
-25.0 C (-13.0 F)
1933
-26.7 C (-16.1 F)
1934
-15.6 C (3.9 F)
1935
-25.0 C (-13.0 F)
1936
-31.7 C (-25.1 F)
1937
-24.4 C (-11.9 F)
1938
-19.4 C (-2.9 F)
1939
-18.9 C (-2.0 F)
1940
-21.7 C (-7.1 F)
1941
-20.6 C (-5.1 F)
1942
-24.4 C (-11.9 F)
1943
-23.3 C (-9.9 F)
1944
-17.2 C (1.0 F)
1945
-16.7 C (1.9 F)
1946
-17.2 C (1.0 F)
1947
-18.9 C (-2.0 F)
1948
-15.0 C (5.0 F)
1949
-21.7 C (-7.1 F)
1950
-25.6 C (-14.1 F)
1951
-27.2 C (-17.0 F)
1952
-17.8 C (0.0 F)
1953
-15.6 C (3.9 F)
1954
-18.9 C (-2.0 F)
1955
-18.3 C (-0.9 F)
1956
-18.3 C (-0.9 F)
1957
-17.2 C (1.0 F)
1958
-14.4 C (6.1 F)
1959
-22.8 C (-9.0 F)
1960
-20.6 C (-5.1 F)
1961
-20.0 C (-4.0 F)
1962
-26.1 C (-15.0 F)
1963
-28.3 C (-18.9 F)
1964
-21.7 C (-7.1 F)
1965
-18.9 C (-2.0 F)
1966
-18.9 C (-2.0 F)
1967
-18.9 C (-2.0 F)
1968
-20.0 C (-4.0 F)
1969
-15.0 C (5.0 F)
1970
-19.4 C (-2.9 F)
1971
-21.1 C (-6.0 F)
1972
-24.4 C (-11.9 F)
1973
-20.0 C (-4.0 F)
1974
-23.3 C (-9.9 F)
Wettest day (Rx1day)
The wettest day of the year at Denver WSO City, 1921 to 1974. The record is 74.4 mm (2.9 in) in 1921, marked on the chart; the median year is 31.8 mm (1.3 in).
Wettest day (Rx1day) at Denver WSO City by year
Year
Wettest day (Rx1day)
1921
74.4 mm (2.9 in)
1922
22.4 mm (0.9 in)
1923
55.4 mm (2.2 in)
1924
23.4 mm (0.9 in)
1925
15.0 mm (0.6 in)
1926
27.4 mm (1.1 in)
1927
35.6 mm (1.4 in)
1928
37.3 mm (1.5 in)
1929
27.9 mm (1.1 in)
1930
21.3 mm (0.8 in)
1931
30.2 mm (1.2 in)
1932
23.9 mm (0.9 in)
1933
24.9 mm (1.0 in)
1934
18.0 mm (0.7 in)
1935
54.9 mm (2.2 in)
1936
45.0 mm (1.8 in)
1937
25.9 mm (1.0 in)
1938
41.4 mm (1.6 in)
1939
13.5 mm (0.5 in)
1940
24.9 mm (1.0 in)
1941
23.9 mm (0.9 in)
1942
32.0 mm (1.3 in)
1943
20.6 mm (0.8 in)
1944
35.1 mm (1.4 in)
1945
31.8 mm (1.3 in)
1946
22.4 mm (0.9 in)
1947
36.8 mm (1.4 in)
1948
8.4 mm (0.33 in)
1949
22.6 mm (0.9 in)
1950
56.6 mm (2.2 in)
1951
34.3 mm (1.4 in)
1952
32.8 mm (1.3 in)
1953
40.1 mm (1.6 in)
1954
36.8 mm (1.4 in)
1955
25.4 mm (1.0 in)
1956
50.3 mm (2.0 in)
1957
48.8 mm (1.9 in)
1958
33.0 mm (1.3 in)
1959
41.4 mm (1.6 in)
1960
30.0 mm (1.2 in)
1961
31.8 mm (1.3 in)
1962
17.5 mm (0.7 in)
1963
38.1 mm (1.5 in)
1964
32.0 mm (1.3 in)
1965
55.4 mm (2.2 in)
1966
17.3 mm (0.7 in)
1967
47.0 mm (1.9 in)
1968
20.6 mm (0.8 in)
1969
60.2 mm (2.4 in)
1970
45.0 mm (1.8 in)
1971
27.2 mm (1.1 in)
1972
28.2 mm (1.1 in)
1973
43.9 mm (1.7 in)
1974
17.8 mm (0.7 in)
Wettest five days (Rx5day)
The wettest five days of the year at Denver WSO City, 1921 to 1974. The record is 119.7 mm (4.7 in) in 1969, marked on the chart; the median year is 48.9 mm (1.9 in).
Wettest five days (Rx5day) at Denver WSO City by year
Year
Wettest five days (Rx5day)
1921
78.5 mm (3.1 in)
1922
46.7 mm (1.8 in)
1923
65.0 mm (2.6 in)
1924
60.0 mm (2.4 in)
1925
19.1 mm (0.8 in)
1926
36.3 mm (1.4 in)
1927
42.2 mm (1.7 in)
1928
57.4 mm (2.3 in)
1929
64.4 mm (2.5 in)
1930
45.0 mm (1.8 in)
1931
67.9 mm (2.7 in)
1932
31.2 mm (1.2 in)
1933
49.5 mm (1.9 in)
1934
33.2 mm (1.3 in)
1935
80.3 mm (3.2 in)
1936
73.0 mm (2.9 in)
1937
37.0 mm (1.5 in)
1938
53.9 mm (2.1 in)
1939
17.1 mm (0.7 in)
1940
31.0 mm (1.2 in)
1941
41.4 mm (1.6 in)
1942
67.5 mm (2.7 in)
1943
34.6 mm (1.4 in)
1944
57.4 mm (2.3 in)
1945
48.1 mm (1.9 in)
1946
51.6 mm (2.0 in)
1947
59.3 mm (2.3 in)
1948
9.4 mm (0.37 in)
1949
59.6 mm (2.3 in)
1950
60.9 mm (2.4 in)
1951
48.2 mm (1.9 in)
1952
36.3 mm (1.4 in)
1953
43.4 mm (1.7 in)
1954
44.2 mm (1.7 in)
1955
39.4 mm (1.6 in)
1956
79.3 mm (3.1 in)
1957
59.1 mm (2.3 in)
1958
48.0 mm (1.9 in)
1959
58.9 mm (2.3 in)
1960
46.5 mm (1.8 in)
1961
65.6 mm (2.6 in)
1962
25.7 mm (1.0 in)
1963
68.9 mm (2.7 in)
1964
62.0 mm (2.4 in)
1965
70.4 mm (2.8 in)
1966
22.8 mm (0.9 in)
1967
54.4 mm (2.1 in)
1968
28.9 mm (1.1 in)
1969
119.7 mm (4.7 in)
1970
53.7 mm (2.1 in)
1971
46.1 mm (1.8 in)
1972
31.0 mm (1.2 in)
1973
83.3 mm (3.3 in)
1974
25.7 mm (1.0 in)
Longest dry spell (CDD)
The longest dry spell of the year at Denver WSO City, 1921 to 1974. The record is 89 days in 1944, marked on the chart; the median year is 31 days.
Longest dry spell (CDD) at Denver WSO City by year
Year
Longest dry spell (CDD)
1921
42 days
1922
27 days
1923
26 days
1924
47 days
1925
42 days
1926
22 days
1927
25 days
1928
48 days
1929
31 days
1930
37 days
1931
42 days
1932
26 days
1933
36 days
1934
56 days
1935
47 days
1936
39 days
1937
29 days
1938
25 days
1939
56 days
1940
31 days
1941
29 days
1942
29 days
1943
42 days
1944
89 days
1945
30 days
1946
32 days
1947
25 days
1948
31 days
1949
40 days
1950
31 days
1951
26 days
1952
32 days
1953
34 days
1954
49 days
1955
29 days
1956
65 days
1957
29 days
1958
26 days
1959
33 days
1960
28 days
1961
34 days
1962
54 days
1963
58 days
1964
30 days
1965
37 days
1966
26 days
1967
22 days
1968
21 days
1969
27 days
1970
63 days
1971
23 days
1972
27 days
1973
34 days
1974
19 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
52 years with a frost
Across 52 years with a frost, the median last spring frost at Denver WSO City falls on 30 April and the median first autumn frost on 15 October, which leaves a median of 164 days between them.
Fitted over all years, the growing season changes by -0.5 days per decade at this station.
Frost dates and growing season at Denver WSO City
Measure
Median, all years
Earliest period
Recent period (1943 to 1973)
Recent against earliest
Fitted trend
Last spring frost
30 April
n/a
1 May
n/a
0.0 days per decade
First autumn frost
15 October
n/a
15 October
n/a
-0.5 days per decade
Growing days
164 days
n/a
163 days
n/a
-0.5 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
52 years, 1921 to 1973
A day with at least 31.6 mm (1.2 in) of rain is expected about once in 2 years. A day with at least 76.8 mm (3.0 in) of rain is expected about once in 100 years.
Rainfall return levels at Denver WSO 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
31.6 mm (1.2 in)
5 years
43.5 mm (1.7 in)
10 years
51.5 mm (2.0 in)
25 years
61.6 mm (2.4 in)
50 years
69.2 mm (2.7 in)
100 years
76.8 mm (3.0 in)
Longer than the 52 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, 52 years of values from 1921 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: 74.4 mm (2.9 in) in 1921; 60.2 mm (2.4 in) in 1969; 56.6 mm (2.2 in) in 1950.
Station Changes
2 suspected
2 changes were suspected in the annual mean temperature of Denver WSO City, at 1949 and 1967. Each is measured against neighbouring stations.
Relative to 5 neighbouring stations, the station's annual mean temperature from 1949 ran 0.2 C (0.4 F) higher than in the years before (possible change).
Relative to 5 neighbouring stations, the station's annual mean temperature from 1967 ran 0.3 C (0.5 F) lower than in the years before (possible change).
Suspected changes in the annual mean temperature at Denver WSO City, against neighbouring stations
Year
Shift (C)
Shift (F)
Strength
Neighbours
1949
+0.2
+0.4
possible
5
1967
-0.3
-0.5
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 Denver WSO City standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Denver WSO 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 2026-10-14 (14 October 2026). Records are computed by this site and are not official.