Bunker 4N Threshold Days by Year (USC00231101)

19 fixed thresholds counted per year at Bunker 4N (USC00231101): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Bunker 4N Thresholds

Bunker 4N: days with 10 mm (0.39 in) or more of precipitation in 46 years, most in 1957 with 52.
Bunker 4N: days with 25 mm (0.98 in) or more of precipitation in 46 years, most in 1973 with 26.
Bunker 4N: days with 50 mm (1.97 in) or more of precipitation in 44 years, most in 1951 with 7.
Bunker 4N: days with a maximum temperature at or above 30 C (86 F) in 30 years, most in 1980 with 102.
19 fixed thresholds have at least one qualifying day at Bunker 4N.

Days at or above 30 C (86 F)

30 years with a qualifying day

Days per year at Bunker 4N with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 102 in 1980.

Days at or above 30 C (86 F) per year at Bunker 4N
Year	Days	Decade average
1964	65	55.5
1965	44	55.5
1966	46	55.5
1967	42	55.5
1968	64	55.5
1969	72	55.5
1970	60	60.4
1971	63	60.4
1972	78	60.4
1973	60	60.4
1974	45	60.4
1975	67	60.4
1976	44	60.4
1977	62	60.4
1978	76	60.4
1979	49	60.4
1980	102	59.2
1981	42	59.2
1982	32	59.2
1983	78	59.2
1984	66	59.2
1985	40	59.2
1987	72	59.2
1988	64	59.2
1989	37	59.2
1991	82	58.2
1995	51	58.2
1996	48	58.2
1997	43	58.2
1998	67	58.2

For each year, a bar from the first to the last day at Bunker 4N meeting 30 C (86 F).

First to last qualifying date each year at Bunker 4N
Year	First date	Last date
1964	1964-05-17	1964-09-10
1965	1965-04-21	1965-09-18
1966	1966-05-07	1966-09-04
1967	1967-03-13	1967-08-30
1968	1968-05-02	1968-09-27
1969	1969-05-28	1969-09-30
1970	1970-04-28	1970-09-30
1971	1971-06-05	1971-09-30
1972	1972-04-12	1972-09-21
1973	1973-05-10	1973-09-03
1974	1974-06-20	1974-08-26
1975	1975-05-18	1975-09-06
1976	1976-06-27	1976-10-03
1977	1977-05-22	1977-09-11
1978	1978-05-24	1978-09-21
1979	1979-05-11	1979-10-09
1980	1980-04-21	1980-10-10
1981	1981-06-09	1981-10-06
1982	1982-06-24	1982-09-02
1983	1983-06-21	1983-10-04
1984	1984-05-13	1984-09-14
1985	1985-04-20	1985-09-07
1987	1987-04-20	1987-09-27
1988	1988-04-05	1988-09-23
1989	1989-04-22	1989-10-14
1991	1991-05-15	1991-10-05
1995	1995-06-08	1995-09-02
1996	1996-05-18	1996-09-12
1997	1997-06-25	1997-09-20
1998	1998-05-14	1998-09-30

Every Fixed Threshold

Fixed thresholds at Bunker 4N
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	30	102	1980	67
35 C (95 F): Days	24	45	1980	4
40 C (104 F): Days	1	13	1980	13
90 F (32.2 C): Days	30	74	1980	22
100 F (37.8 C): Days	8	19	1980	1
0 C (32 F): Ice days (max	30	38	1978	8
0 C (32 F): Frost days (min	30	133	1988	73
-10 C (14 F): Days with min	30	43	1988	4
-20 C (-4 F): Days with min	20	10	1983	7
-30 C (-22 F): Days with min	2	2	1989	2
20 C (68 F): Tropical nights (min	30	56	1991	33
25 C (77 F): Days with min	2	2	1991	2
10 mm (0.39 in): Days with 10 mm or more rain	46	52	1957	33
25 mm (0.98 in): Days with 25 mm or more rain	46	26	1973	11
50 mm (1.97 in): Days with 50 mm or more rain	44	7	1951	2
100 mm (3.94 in): Days with 100 mm or more rain	10	2	1957	1
200 mm (7.87 in): Days with 200 mm or more rain	1	1	1983	1
10 cm (3.9 in): Days with 10 cm or more snowfall	18	5	1960	2
25 cm (9.8 in): Days with 25 cm or more snowfall	1	1	1951	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1964.

Download the Data

Data for Bunker 4N 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).

Bunker 4N Threshold Days by Year (USC00231101)

Key Facts for Bunker 4N Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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