Chalk River Aecl Threshold Days by Year (CA006101335)

15 fixed thresholds counted per year at Chalk River Aecl (CA006101335): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Chalk River Aecl Thresholds

Chalk River Aecl: days with a maximum temperature at or above 30 C (86 F) in 20 years, most in 1975 with 25.
Chalk River Aecl: days with a maximum temperature at or below 0 C (32 F) in 20 years, most in 1976 with 108.
Chalk River Aecl: nights with a minimum temperature at or below 0 C (32 F) in 19 years, most in 1967 with 187.
Chalk River Aecl: nights with a minimum temperature at or below -10 C (14 F) in 19 years, most in 1978 with 101.
15 fixed thresholds have at least one qualifying day at Chalk River Aecl.

Days at or above 30 C (86 F)

20 years with a qualifying day

Days per year at Chalk River Aecl with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 25 in 1975.

Days at or above 30 C (86 F) per year at Chalk River Aecl
Year	Days	Decade average
1963	23	12.5
1964	20	12.5
1965	6	12.5
1966	14	12.5
1967	5	12.5
1968	7	12.5
1970	13	12.8
1971	13	12.8
1972	3	12.8
1973	14	12.8
1974	9	12.8
1975	25	12.8
1976	15	12.8
1977	15	12.8
1978	12	12.8
1979	9	12.8
1980	4	9
1981	7	9
1982	5	9
1983	20	9

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

First to last qualifying date each year at Chalk River Aecl
Year	First date	Last date
1963	1963-06-02	1963-07-28
1964	1964-05-06	1964-08-30
1965	1965-05-26	1965-08-15
1966	1966-05-24	1966-07-25
1967	1967-06-03	1967-08-17
1968	1968-06-05	1968-07-18
1970	1970-06-09	1970-08-14
1971	1971-05-18	1971-08-19
1972	1972-05-23	1972-07-12
1973	1973-07-03	1973-09-03
1974	1974-06-05	1974-08-22
1975	1975-05-20	1975-08-25
1976	1976-04-18	1976-08-22
1977	1977-05-16	1977-08-28
1978	1978-05-25	1978-08-15
1979	1979-05-08	1979-09-01
1980	1980-05-22	1980-08-06
1981	1981-07-06	1981-08-01
1982	1982-07-06	1982-09-13
1983	1983-06-13	1983-09-05

Every Fixed Threshold

Fixed thresholds at Chalk River Aecl
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	20	25	1975	20
35 C (95 F): Days	5	2	1966	2
90 F (32.2 C): Days	16	14	1963	6
100 F (37.8 C): Days	1	1	1977	1
0 C (32 F): Ice days (max	20	108	1976	88
0 C (32 F): Frost days (min	19	187	1967	186
-10 C (14 F): Days with min	19	101	1978	78
-20 C (-4 F): Days with min	19	46	1976	27
-30 C (-22 F): Days with min	18	10	1979	2
20 C (68 F): Tropical nights (min	15	6	1973	1
10 mm (0.39 in): Days with 10 mm or more rain	18	36	1972	32
25 mm (0.98 in): Days with 25 mm or more rain	17	7	1973	2
50 mm (1.97 in): Days with 50 mm or more rain	3	1	1965	1
10 cm (3.9 in): Days with 10 cm or more snowfall	17	9	1971	7
25 cm (9.8 in): Days with 25 cm or more snowfall	6	2	1972	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1963.

Download the Data

Data for Chalk River Aecl 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 2026-10-17. Last revised 17 October 2026 (2026-10-17).

Chalk River Aecl Threshold Days by Year (CA006101335)

Key Facts for Chalk River Aecl Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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