Copper Lake Threshold Days by Year (CA008201100)

14 fixed thresholds counted per year at Copper Lake (CA008201100): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Copper Lake Thresholds

Copper Lake: days with a maximum temperature at or below 0 C (32 F) in 23 years, most in 1972 with 77.
Copper Lake: nights with a minimum temperature at or below 0 C (32 F) in 23 years, most in 1972 with 201.
Copper Lake: nights with a minimum temperature at or below -10 C (14 F) in 23 years, most in 1972 with 76.
Copper Lake: days with 10 mm (0.39 in) or more of precipitation in 23 years, most in 1972 with 66.
14 fixed thresholds have at least one qualifying day at Copper Lake.

Days at or above 30 C (86 F)

19 years with a qualifying day

Days per year at Copper Lake with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 14 in 1949.

Days at or above 30 C (86 F) per year at Copper Lake
Year	Days	Decade average
1946	2	7.3
1947	12	7.3
1948	1	7.3
1949	14	7.3
1952	6	2.5
1953	1	2.5
1954	1	2.5
1955	5	2.5
1957	1	2.5
1959	1	2.5
1960	4	4.6
1961	5	4.6
1967	6	4.6
1968	2	4.6
1969	6	4.6
1970	6	3
1971	2	3
1972	3	3
1973	1	3

For each year, a bar from the first to the last day at Copper Lake meeting 30 C (86 F).

First to last qualifying date each year at Copper Lake
Year	First date	Last date
1946	1946-06-27	1946-07-19
1947	1947-06-29	1947-09-11
1948	1948-07-01	1948-07-01
1949	1949-06-04	1949-08-28
1952	1952-07-08	1952-08-29
1953	1953-08-31	1953-08-31
1954	1954-06-22	1954-06-22
1955	1955-05-23	1955-08-22
1957	1957-06-16	1957-06-16
1959	1959-07-28	1959-07-28
1960	1960-06-28	1960-09-08
1961	1961-05-14	1961-09-11
1967	1967-06-04	1967-08-16
1968	1968-07-09	1968-08-04
1969	1969-06-14	1969-09-01
1970	1970-07-26	1970-08-16
1971	1971-07-01	1971-08-10
1972	1972-05-29	1972-07-13
1973	1973-07-09	1973-07-09

Every Fixed Threshold

Fixed thresholds at Copper Lake
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	19	14	1949	1
90 F (32.2 C): Days	8	6	1949	2
0 C (32 F): Ice days (max	23	77	1972	56
0 C (32 F): Frost days (min	23	201	1972	169
-10 C (14 F): Days with min	23	76	1972	45
-20 C (-4 F): Days with min	22	19	1950	11
-30 C (-22 F): Days with min	6	4	1971	4
20 C (68 F): Tropical nights (min	1	1	1971	1
10 mm (0.39 in): Days with 10 mm or more rain	23	66	1972	51
25 mm (0.98 in): Days with 25 mm or more rain	23	21	1953	15
50 mm (1.97 in): Days with 50 mm or more rain	20	3	1948	2
100 mm (3.94 in): Days with 100 mm or more rain	3	1	1956	1
10 cm (3.9 in): Days with 10 cm or more snowfall	23	18	1972	8
25 cm (9.8 in): Days with 25 cm or more snowfall	19	4	1956	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1946.

Download the Data

Data for Copper Lake 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 2026-10-17 (17 October 2026). Threshold counts are computed by this site.

Data as of 2025-12-31. Last revised 31 December 2025 (2025-12-31).

Copper Lake Threshold Days by Year (CA008201100)

Key Facts for Copper Lake Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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