Record envelope, standing records and threshold days for Idaho Springs (USC00054234), Colorado, United States, with 82 years of record.
Key Facts for Idaho Springs
Idaho Springs (USC00054234) is a weather station in Colorado, United States at 39.75 latitude and -105.52 longitude, 2,303 m (7,555 ft) above sea level.
The station reports from 1893 to 1974, 82 years of record.
1,464 records set at Idaho Springs still stand.
Records are tracked for tmax, tmin, prcp, snow: an element needs 30 years of data to be eligible.
Idaho Springs tied a daily record high minimum temperature of 12.8 C (55.0 F) on 28 June 1974.
About the Station
Location: Colorado, United States, 39.75 latitude, -105.52 longitude.
Elevation: 2,303 m (7,555 ft).
Period of record: 1893 to 1974, 82 years.
Eligible elements: tmax, tmin, prcp, snow.
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 Idaho Springs. 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 Idaho Springs, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
16.7 C (62.1 F)
-35.6 C (-32.1 F)
n/a
n/a
Feb
19.4 C (66.9 F)
-33.9 C (-29.0 F)
n/a
n/a
Mar
22.8 C (73.0 F)
-30.6 C (-23.1 F)
n/a
n/a
Apr
26.1 C (79.0 F)
-21.1 C (-6.0 F)
n/a
n/a
May
31.7 C (89.1 F)
-13.3 C (8.1 F)
n/a
n/a
Jun
35.0 C (95.0 F)
-5.0 C (23.0 F)
n/a
n/a
Jul
33.9 C (93.0 F)
-2.2 C (28.0 F)
n/a
n/a
Aug
32.8 C (91.0 F)
-2.2 C (28.0 F)
n/a
n/a
Sep
33.3 C (91.9 F)
-10.0 C (14.0 F)
n/a
n/a
Oct
28.3 C (82.9 F)
-19.4 C (-2.9 F)
n/a
n/a
Nov
21.7 C (71.1 F)
-29.4 C (-20.9 F)
n/a
n/a
Dec
18.9 C (66.0 F)
-31.1 C (-24.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Idaho Springs still stand. 1962 holds the most, with 64.
Standing records at Idaho Springs by the year they were set
Year set
Standing records
1893
9
1894
5
1905
16
1906
27
1907
25
1908
15
1909
22
1910
28
1911
18
1912
12
1913
25
1914
13
1915
22
1916
26
1917
29
1918
24
1919
21
1920
15
1921
22
1922
20
1923
22
1924
14
1925
11
1926
20
1927
30
1928
18
1929
22
1930
24
1931
25
1932
21
1933
31
1934
12
1935
19
1936
19
1937
26
1938
17
1939
19
1940
12
1941
9
1942
20
1943
23
1944
15
1945
21
1946
20
1947
23
1948
33
1949
12
1950
28
1951
34
1952
18
1953
20
1954
20
1955
14
1956
12
1957
18
1958
30
1959
33
1960
40
1961
21
1962
64
1963
22
1964
12
1965
22
1966
14
1967
7
1968
9
1969
21
1970
10
1971
7
1972
11
1973
10
1974
35
All-Time Record Progression
7 new records
7 all-time records were set at Idaho Springs between 23 June 1943 and 30 June 1972. Each dot is a new record.
When Idaho Springs set new all-time records
Date
Kind
Detail
1943-06-23
Record high maximum temperature
Record high maximum temperature 33.9 C (93.0 F)
1948-01-27
Record low minimum temperature
Record low minimum temperature -34.4 C (-29.9 F)
1954-06-23
Record high maximum temperature
Record high maximum temperature 34.4 C (93.9 F)
1962-01-10
Record low minimum temperature
Record low minimum temperature -35.0 C (-31.0 F)
1963-01-11
Record low maximum temperature
Record low maximum temperature -23.3 C (-9.9 F)
1963-01-12
Record low minimum temperature
Record low minimum temperature -35.6 C (-32.1 F)
1972-06-30
Record high maximum temperature
Record high maximum temperature 35.0 C (95.0 F)
Wettest Day of Each Month
Apr: 121.9 mm (4.8 in)
The wettest day on record for each calendar month at Idaho Springs. The most was 121.9 mm (4.8 in) on 15 April 1921.
Record daily precipitation for each month at Idaho Springs
Month
Record daily precipitation (mm)
Date
Jan
19.1 mm (0.8 in)
8 January 1962
Feb
31.2 mm (1.2 in)
17 February 1934
Mar
37.6 mm (1.5 in)
21 March 1944
Apr
121.9 mm (4.8 in)
15 April 1921
May
104.1 mm (4.1 in)
7 May 1969
Jun
77.2 mm (3.0 in)
4 June 1949
Jul
45.2 mm (1.8 in)
27 July 1946
Aug
52.8 mm (2.1 in)
3 August 1951
Sep
52.3 mm (2.1 in)
10 September 1933
Oct
48.3 mm (1.9 in)
18 October 1908
Nov
48.3 mm (1.9 in)
2 November 1946
Dec
31.8 mm (1.3 in)
4 December 1913
Period of Record Coverage
1893 to 1974
Complete yearUnder 90 percent of days
72 years of record at Idaho Springs, 1893 to 1974. 13 years have data for under 90 percent of days and are left out of rankings: 1893, 1894, 1905, 1916, 1937, 1941, 1942, 1956 and others.
Cooler than the station meanWarmer than the station mean
One stripe for each of 57 complete years at Idaho Springs, 1906 to 1970. Blue stripes are years cooler than the station's own mean of 6.2 C (43.2 F); red stripes are warmer. The coolest year was 1923, at 4.5 C (40.0 F), and the warmest was 1910, at 8.0 C (46.4 F). The strongest colour marks a difference of 1.8 C (3.2 F).
Annual mean temperature at Idaho Springs as warming stripes, 1906 to 1970
Year
Annual mean temperature
Difference from the station mean
1906
7.0 C
+0.70 C
1907
7.3 C
+1.08 C
1908
6.8 C
+0.51 C
1909
6.5 C
+0.22 C
1910
8.0 C
+1.73 C
1912
5.9 C
-0.38 C
1913
6.0 C
-0.24 C
1914
7.1 C
+0.80 C
1915
6.2 C
-0.01 C
1917
6.1 C
-0.14 C
1918
6.8 C
+0.58 C
1919
7.2 C
+0.98 C
1920
6.1 C
-0.14 C
1921
7.0 C
+0.76 C
1922
5.2 C
-1.05 C
1923
4.5 C
-1.80 C
1924
5.0 C
-1.24 C
1925
5.7 C
-0.51 C
1926
5.5 C
-0.72 C
1927
5.5 C
-0.79 C
1928
5.5 C
-0.74 C
1929
4.7 C
-1.58 C
1930
5.4 C
-0.84 C
1931
6.1 C
-0.16 C
1932
5.4 C
-0.88 C
1933
6.5 C
+0.24 C
1934
7.3 C
+1.08 C
1935
5.8 C
-0.43 C
1936
5.9 C
-0.37 C
1938
7.3 C
+1.03 C
1939
7.6 C
+1.38 C
1940
7.2 C
+0.94 C
1943
7.3 C
+1.04 C
1944
5.9 C
-0.31 C
1945
5.9 C
-0.40 C
1946
6.7 C
+0.48 C
1947
5.6 C
-0.61 C
1948
5.1 C
-1.19 C
1949
6.0 C
-0.21 C
1950
6.5 C
+0.28 C
1951
4.9 C
-1.31 C
1952
6.3 C
+0.05 C
1953
6.9 C
+0.64 C
1954
7.9 C
+1.65 C
1955
6.1 C
-0.20 C
1957
6.6 C
+0.38 C
1959
6.4 C
+0.10 C
1960
5.8 C
-0.41 C
1961
5.7 C
-0.56 C
1962
6.3 C
+0.06 C
1963
7.5 C
+1.24 C
1964
5.6 C
-0.64 C
1965
6.1 C
-0.16 C
1966
6.7 C
+0.49 C
1967
6.1 C
-0.16 C
1969
6.2 C
-0.02 C
1970
5.9 C
-0.36 C
The fitted trend in annual mean temperature here over 1906 to 1970 is -0.02 C (-0.14 to 0.09) per decade. The interval includes zero, so the trend is not clearly different from zero. In Fahrenheit: -0.04 F (-0.25 to 0.16) per decade. The slope is a straight line fitted to 57 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Idaho Springs
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
-0.02 C (-0.14 to 0.09) per decade
-0.04 F (-0.25 to 0.16) per decade
1906 to 1970
57
Not clearly different from zero
Mean daily maximum
0.3 C (0.1 to 0.4) per decade
0.5 F (0.1 to 0.8) per decade
1906 to 1970
57
Rise
Mean daily minimum
-0.3 C (-0.4 to -0.2) per decade
-0.5 F (-0.8 to -0.3) per decade
1906 to 1970
57
Fall
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 1974
Yearly extremes at Idaho Springs: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
35.0 C (95.0 F)
1972
31.1 C (88.0 F)
72
Coldest night (TNn)
-35.6 C (-32.1 F)
1963
-24.4 C (-11.9 F)
72
Wettest day (Rx1day)
121.9 mm (4.8 in)
1921
31.8 mm (1.3 in)
72
Wettest five days (Rx5day)
168.3 mm (6.6 in)
1969
49.7 mm (2.0 in)
72
Longest dry spell (CDD)
65 days
1956
33 days
72
Hottest day (TXx)
The hottest day of the year at Idaho Springs, 1893 to 1974. The record is 35.0 C (95.0 F) in 1972, marked on the chart; the median year is 31.1 C (88.0 F).
Hottest day (TXx) at Idaho Springs by year
Year
Hottest day (TXx)
1893
29.4 C (84.9 F)
1894
17.2 C (63.0 F)
1905
31.7 C (89.1 F)
1906
30.0 C (86.0 F)
1907
28.9 C (84.0 F)
1908
29.4 C (84.9 F)
1909
30.0 C (86.0 F)
1910
32.2 C (90.0 F)
1911
33.3 C (91.9 F)
1912
29.4 C (84.9 F)
1913
30.6 C (87.1 F)
1914
30.0 C (86.0 F)
1915
31.1 C (88.0 F)
1916
33.3 C (91.9 F)
1917
30.0 C (86.0 F)
1918
31.1 C (88.0 F)
1919
32.2 C (90.0 F)
1920
31.1 C (88.0 F)
1921
29.4 C (84.9 F)
1922
30.6 C (87.1 F)
1923
28.9 C (84.0 F)
1924
31.1 C (88.0 F)
1925
28.9 C (84.0 F)
1926
29.4 C (84.9 F)
1927
31.1 C (88.0 F)
1928
30.0 C (86.0 F)
1929
30.0 C (86.0 F)
1930
29.4 C (84.9 F)
1931
32.8 C (91.0 F)
1932
29.4 C (84.9 F)
1933
30.0 C (86.0 F)
1934
32.2 C (90.0 F)
1935
30.0 C (86.0 F)
1936
32.2 C (90.0 F)
1937
30.6 C (87.1 F)
1938
32.2 C (90.0 F)
1939
32.8 C (91.0 F)
1940
32.2 C (90.0 F)
1941
30.6 C (87.1 F)
1942
32.2 C (90.0 F)
1943
33.9 C (93.0 F)
1944
32.2 C (90.0 F)
1945
30.0 C (86.0 F)
1946
31.1 C (88.0 F)
1947
31.7 C (89.1 F)
1948
32.2 C (90.0 F)
1949
30.0 C (86.0 F)
1950
31.1 C (88.0 F)
1951
31.1 C (88.0 F)
1952
31.1 C (88.0 F)
1953
31.1 C (88.0 F)
1954
34.4 C (93.9 F)
1955
31.1 C (88.0 F)
1956
30.0 C (86.0 F)
1957
33.3 C (91.9 F)
1958
33.3 C (91.9 F)
1959
32.8 C (91.0 F)
1960
33.9 C (93.0 F)
1961
31.1 C (88.0 F)
1962
32.8 C (91.0 F)
1963
32.8 C (91.0 F)
1964
31.1 C (88.0 F)
1965
29.4 C (84.9 F)
1966
31.7 C (89.1 F)
1967
29.4 C (84.9 F)
1968
30.0 C (86.0 F)
1969
31.1 C (88.0 F)
1970
31.1 C (88.0 F)
1971
32.2 C (90.0 F)
1972
35.0 C (95.0 F)
1973
29.4 C (84.9 F)
1974
31.7 C (89.1 F)
Coldest night (TNn)
The coldest night of the year at Idaho Springs, 1893 to 1974. The record is -35.6 C (-32.1 F) in 1963, marked on the chart; the median year is -24.4 C (-11.9 F).
Coldest night (TNn) at Idaho Springs by year
Year
Coldest night (TNn)
1893
-20.0 C (-4.0 F)
1894
-24.4 C (-11.9 F)
1905
-24.4 C (-11.9 F)
1906
-20.6 C (-5.1 F)
1907
-16.7 C (1.9 F)
1908
-21.7 C (-7.1 F)
1909
-22.8 C (-9.0 F)
1910
-25.6 C (-14.1 F)
1911
-24.4 C (-11.9 F)
1912
-22.2 C (-8.0 F)
1913
-33.9 C (-29.0 F)
1914
-27.2 C (-17.0 F)
1915
-23.9 C (-11.0 F)
1916
-29.4 C (-20.9 F)
1917
-26.7 C (-16.1 F)
1918
-25.0 C (-13.0 F)
1919
-30.0 C (-22.0 F)
1920
-22.8 C (-9.0 F)
1921
-17.8 C (0.0 F)
1922
-24.4 C (-11.9 F)
1923
-29.4 C (-20.9 F)
1924
-31.1 C (-24.0 F)
1925
-18.9 C (-2.0 F)
1926
-26.7 C (-16.1 F)
1927
-26.1 C (-15.0 F)
1928
-24.4 C (-11.9 F)
1929
-29.4 C (-20.9 F)
1930
-32.2 C (-26.0 F)
1931
-22.8 C (-9.0 F)
1932
-28.9 C (-20.0 F)
1933
-33.9 C (-29.0 F)
1934
-16.7 C (1.9 F)
1935
-26.7 C (-16.1 F)
1936
-24.4 C (-11.9 F)
1937
-28.3 C (-18.9 F)
1938
-20.0 C (-4.0 F)
1939
-21.7 C (-7.1 F)
1940
-25.6 C (-14.1 F)
1941
-21.7 C (-7.1 F)
1942
-22.8 C (-9.0 F)
1943
-30.6 C (-23.1 F)
1944
-23.3 C (-9.9 F)
1945
-20.6 C (-5.1 F)
1946
-24.4 C (-11.9 F)
1947
-24.4 C (-11.9 F)
1948
-34.4 C (-29.9 F)
1949
-26.1 C (-15.0 F)
1950
-29.4 C (-20.9 F)
1951
-32.8 C (-27.0 F)
1952
-25.6 C (-14.1 F)
1953
-25.0 C (-13.0 F)
1954
-24.4 C (-11.9 F)
1955
-25.0 C (-13.0 F)
1956
-25.0 C (-13.0 F)
1957
-20.6 C (-5.1 F)
1958
-21.1 C (-6.0 F)
1959
-24.4 C (-11.9 F)
1960
-28.3 C (-18.9 F)
1961
-25.0 C (-13.0 F)
1962
-35.0 C (-31.0 F)
1963
-35.6 C (-32.1 F)
1964
-22.8 C (-9.0 F)
1965
-26.7 C (-16.1 F)
1966
-24.4 C (-11.9 F)
1967
-22.8 C (-9.0 F)
1968
-22.2 C (-8.0 F)
1969
-24.4 C (-11.9 F)
1970
-21.1 C (-6.0 F)
1971
-27.2 C (-17.0 F)
1972
-27.8 C (-18.0 F)
1973
-23.3 C (-9.9 F)
1974
-18.9 C (-2.0 F)
Wettest day (Rx1day)
The wettest day of the year at Idaho Springs, 1893 to 1974. The record is 121.9 mm (4.8 in) in 1921, marked on the chart; the median year is 31.8 mm (1.3 in).
Wettest day (Rx1day) at Idaho Springs by year
Year
Wettest day (Rx1day)
1893
9.7 mm (0.38 in)
1894
12.4 mm (0.5 in)
1905
45.0 mm (1.8 in)
1906
33.8 mm (1.3 in)
1907
24.4 mm (1.0 in)
1908
48.3 mm (1.9 in)
1909
24.1 mm (0.9 in)
1910
31.8 mm (1.3 in)
1911
22.4 mm (0.9 in)
1912
35.3 mm (1.4 in)
1913
32.8 mm (1.3 in)
1914
34.3 mm (1.4 in)
1915
16.0 mm (0.6 in)
1916
32.8 mm (1.3 in)
1917
27.4 mm (1.1 in)
1918
31.5 mm (1.2 in)
1919
19.1 mm (0.8 in)
1920
40.9 mm (1.6 in)
1921
121.9 mm (4.8 in)
1922
37.6 mm (1.5 in)
1923
49.5 mm (1.9 in)
1924
35.8 mm (1.4 in)
1925
27.9 mm (1.1 in)
1926
50.8 mm (2.0 in)
1927
21.3 mm (0.8 in)
1928
24.6 mm (1.0 in)
1929
26.7 mm (1.1 in)
1930
19.8 mm (0.8 in)
1931
21.6 mm (0.9 in)
1932
23.4 mm (0.9 in)
1933
52.3 mm (2.1 in)
1934
31.2 mm (1.2 in)
1935
40.1 mm (1.6 in)
1936
46.5 mm (1.8 in)
1937
25.9 mm (1.0 in)
1938
40.6 mm (1.6 in)
1939
10.7 mm (0.4 in)
1940
32.0 mm (1.3 in)
1941
29.2 mm (1.1 in)
1942
58.4 mm (2.3 in)
1943
23.9 mm (0.9 in)
1944
70.9 mm (2.8 in)
1945
31.8 mm (1.3 in)
1946
48.3 mm (1.9 in)
1947
29.0 mm (1.1 in)
1948
38.6 mm (1.5 in)
1949
77.2 mm (3.0 in)
1950
26.7 mm (1.1 in)
1951
52.8 mm (2.1 in)
1952
34.5 mm (1.4 in)
1953
25.4 mm (1.0 in)
1954
19.6 mm (0.8 in)
1955
22.9 mm (0.9 in)
1956
15.2 mm (0.6 in)
1957
71.4 mm (2.8 in)
1958
16.5 mm (0.6 in)
1959
25.1 mm (1.0 in)
1960
35.8 mm (1.4 in)
1961
34.0 mm (1.3 in)
1962
19.1 mm (0.8 in)
1963
51.6 mm (2.0 in)
1964
22.6 mm (0.9 in)
1965
33.0 mm (1.3 in)
1966
21.3 mm (0.8 in)
1967
33.0 mm (1.3 in)
1968
26.9 mm (1.1 in)
1969
104.1 mm (4.1 in)
1970
42.2 mm (1.7 in)
1971
30.5 mm (1.2 in)
1972
63.5 mm (2.5 in)
1973
57.2 mm (2.3 in)
1974
0.0 mm (0.00 in)
Wettest five days (Rx5day)
The wettest five days of the year at Idaho Springs, 1893 to 1974. The record is 168.3 mm (6.6 in) in 1969, marked on the chart; the median year is 49.7 mm (2.0 in).
Wettest five days (Rx5day) at Idaho Springs by year
Year
Wettest five days (Rx5day)
1893
9.7 mm (0.38 in)
1894
12.7 mm (0.5 in)
1905
62.0 mm (2.4 in)
1906
51.6 mm (2.0 in)
1907
42.3 mm (1.7 in)
1908
67.3 mm (2.6 in)
1909
55.3 mm (2.2 in)
1910
76.5 mm (3.0 in)
1911
27.5 mm (1.1 in)
1912
59.8 mm (2.4 in)
1913
47.2 mm (1.9 in)
1914
53.4 mm (2.1 in)
1915
36.1 mm (1.4 in)
1916
58.0 mm (2.3 in)
1917
54.8 mm (2.2 in)
1918
79.2 mm (3.1 in)
1919
41.5 mm (1.6 in)
1920
58.9 mm (2.3 in)
1921
135.0 mm (5.3 in)
1922
62.3 mm (2.5 in)
1923
68.8 mm (2.7 in)
1924
35.8 mm (1.4 in)
1925
46.9 mm (1.8 in)
1926
64.8 mm (2.6 in)
1927
40.8 mm (1.6 in)
1928
39.6 mm (1.6 in)
1929
63.5 mm (2.5 in)
1930
37.9 mm (1.5 in)
1931
26.3 mm (1.0 in)
1932
33.1 mm (1.3 in)
1933
93.8 mm (3.7 in)
1934
69.8 mm (2.7 in)
1935
43.2 mm (1.7 in)
1936
54.2 mm (2.1 in)
1937
45.8 mm (1.8 in)
1938
58.4 mm (2.3 in)
1939
16.1 mm (0.6 in)
1940
48.5 mm (1.9 in)
1941
22.1 mm (0.9 in)
1942
70.8 mm (2.8 in)
1943
37.7 mm (1.5 in)
1944
116.9 mm (4.6 in)
1945
50.9 mm (2.0 in)
1946
81.9 mm (3.2 in)
1947
70.9 mm (2.8 in)
1948
38.6 mm (1.5 in)
1949
115.8 mm (4.6 in)
1950
38.1 mm (1.5 in)
1951
75.3 mm (3.0 in)
1952
38.6 mm (1.5 in)
1953
36.9 mm (1.5 in)
1954
25.6 mm (1.0 in)
1955
40.6 mm (1.6 in)
1956
36.6 mm (1.4 in)
1957
101.9 mm (4.0 in)
1958
19.3 mm (0.8 in)
1959
48.0 mm (1.9 in)
1960
36.6 mm (1.4 in)
1961
60.7 mm (2.4 in)
1962
24.9 mm (1.0 in)
1963
70.8 mm (2.8 in)
1964
39.3 mm (1.5 in)
1965
64.5 mm (2.5 in)
1966
40.7 mm (1.6 in)
1967
47.3 mm (1.9 in)
1968
33.5 mm (1.3 in)
1969
168.3 mm (6.6 in)
1970
54.9 mm (2.2 in)
1971
55.1 mm (2.2 in)
1972
88.9 mm (3.5 in)
1973
64.8 mm (2.6 in)
1974
0.0 mm (0.00 in)
Longest dry spell (CDD)
The longest dry spell of the year at Idaho Springs, 1893 to 1974. The record is 65 days in 1956, marked on the chart; the median year is 33 days.
Longest dry spell (CDD) at Idaho Springs by year
Year
Longest dry spell (CDD)
1893
39 days
1894
28 days
1905
28 days
1906
39 days
1907
27 days
1908
28 days
1909
34 days
1910
28 days
1911
15 days
1912
19 days
1913
34 days
1914
30 days
1915
35 days
1916
18 days
1917
35 days
1918
24 days
1919
24 days
1920
35 days
1921
4 days
1922
15 days
1923
26 days
1924
28 days
1925
30 days
1926
27 days
1927
41 days
1928
32 days
1929
18 days
1930
32 days
1931
39 days
1932
26 days
1933
38 days
1934
35 days
1935
57 days
1936
46 days
1937
29 days
1938
16 days
1939
57 days
1940
40 days
1941
44 days
1942
32 days
1943
41 days
1944
43 days
1945
27 days
1946
37 days
1947
39 days
1948
24 days
1949
41 days
1950
37 days
1951
28 days
1952
35 days
1953
41 days
1954
36 days
1955
33 days
1956
65 days
1957
24 days
1958
26 days
1959
29 days
1960
27 days
1961
28 days
1962
28 days
1963
34 days
1964
48 days
1965
38 days
1966
28 days
1967
24 days
1968
50 days
1969
51 days
1970
34 days
1971
31 days
1972
38 days
1973
35 days
1974
61 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
57 years with a frost
Across 57 years with a frost, the median last spring frost at Idaho Springs falls on 2 June and the median first autumn frost on 19 September, which leaves a median of 107 days between them.
Fitted over all years, the growing season changes by -3.5 days per decade at this station.
Frost dates and growing season at Idaho Springs
Measure
Median, all years
Earliest period
Recent period (1935 to 1970)
Recent against earliest
Fitted trend
Last spring frost
2 June
n/a
6 June
n/a
+2.3 days per decade
First autumn frost
19 September
n/a
15 September
n/a
-1.2 days per decade
Growing days
107 days
n/a
95 days
n/a
-3.5 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
58 years, 1905 to 1970
A day with at least 30.6 mm (1.2 in) of rain is expected about once in 2 years. A day with at least 99.0 mm (3.9 in) of rain is expected about once in 100 years.
Rainfall return levels at Idaho Springs: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
30.6 mm (1.2 in)
5 years
44.0 mm (1.7 in)
10 years
54.6 mm (2.1 in)
25 years
70.2 mm (2.8 in)
50 years
83.8 mm (3.3 in)
100 years
99.0 mm (3.9 in)
Longer than the 58 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, 58 years of values from 1905 to 1970.
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: 104.1 mm (4.1 in) in 1969; 77.2 mm (3.0 in) in 1949; 71.4 mm (2.8 in) in 1957.
Station Changes
No change in the annual mean temperature of this station was found against its neighbours.
Download the Data
Data for Idaho Springs standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Idaho Springs 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.