Islip-Li Macarthur AP Threshold Days by Year (USW00004781)

19 fixed thresholds counted per year at Islip-Li Macarthur AP (USW00004781): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Islip-Li Macarthur AP Thresholds

Islip-Li Macarthur AP: days with a maximum temperature at or above 30 C (86 F) in 63 years, most in 2010 with 39.
Islip-Li Macarthur AP: days with a maximum temperature at or below 0 C (32 F) in 63 years, most in 1978 with 46.
Islip-Li Macarthur AP: nights with a minimum temperature at or below 0 C (32 F) in 63 years, most in 1967 with 129.
Islip-Li Macarthur AP: nights with a minimum temperature at or below -10 C (14 F) in 63 years, most in 1968 with 36.
19 fixed thresholds have at least one qualifying day at Islip-Li Macarthur AP.

Days at or above 30 C (86 F)

63 years with a qualifying day

Days per year at Islip-Li Macarthur AP with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 39 in 2010.

Days at or above 30 C (86 F) per year at Islip-Li Macarthur AP
Year	Days	Decade average
1964	11	13.5
1965	10	13.5
1966	26	13.5
1967	2	13.5
1968	12	13.5
1969	20	13.5
1970	14	14.2
1971	12	14.2
1972	10	14.2
1973	23	14.2
1974	16	14.2
1975	18	14.2
1976	15	14.2
1977	20	14.2
1978	6	14.2
1979	8	14.2
1980	33	17.6
1981	9	17.6
1982	10	17.6
1983	25	17.6
1984	15	17.6
1985	9	17.6
1986	11	17.6
1987	18	17.6
1988	26	17.6
1989	20	17.6
1990	17	23.2
1991	35	23.2
1992	13	23.2
1993	23	23.2
1994	20	23.2
1995	25	23.2
1996	8	23.2
1997	27	23.2
1998	30	23.2
1999	34	23.2
2000	11	16.8
2001	17	16.8
2002	33	16.8
2003	16	16.8
2004	2	16.8
2005	28	16.8
2006	16	16.8
2007	17	16.8
2008	16	16.8
2009	12	16.8
2010	39	28.2
2011	28	28.2
2012	27	28.2
2013	24	28.2
2014	14	28.2
2015	27	28.2
2016	35	28.2
2017	24	28.2
2018	32	28.2
2019	32	28.2
2020	32	25.4
2021	25	25.4
2022	36	25.4
2023	17	25.4
2024	18	25.4
2025	31	25.4
2026	19	25.4

For each year, a bar from the first to the last day at Islip-Li Macarthur AP meeting 30 C (86 F).

First to last qualifying date each year at Islip-Li Macarthur AP
Year	First date	Last date
1964	1964-05-23	1964-09-09
1965	1965-05-04	1965-08-27
1966	1966-06-21	1966-09-02
1967	1967-07-12	1967-07-25
1968	1968-06-06	1968-08-25
1969	1969-05-29	1969-09-02
1970	1970-07-18	1970-09-23
1971	1971-06-04	1971-08-10
1972	1972-07-12	1972-08-26
1973	1973-06-09	1973-09-04
1974	1974-06-06	1974-08-30
1975	1975-05-20	1975-08-22
1976	1976-04-17	1976-09-14
1977	1977-04-12	1977-09-03
1978	1978-06-28	1978-08-29
1979	1979-07-12	1979-08-08
1980	1980-05-23	1980-09-23
1981	1981-07-07	1981-09-12
1982	1982-07-10	1982-09-12
1983	1983-06-12	1983-09-20
1984	1984-06-07	1984-08-16
1985	1985-07-20	1985-09-06
1986	1986-05-06	1986-08-09
1987	1987-05-29	1987-08-18
1988	1988-05-31	1988-08-17
1989	1989-06-01	1989-09-11
1990	1990-04-28	1990-09-11
1991	1991-05-12	1991-09-17
1992	1992-05-21	1992-08-27
1993	1993-06-10	1993-09-03
1994	1994-05-23	1994-08-27
1995	1995-06-08	1995-08-24
1996	1996-05-20	1996-09-10
1997	1997-06-10	1997-10-06
1998	1998-05-16	1998-09-27
1999	1999-05-29	1999-08-29
2000	2000-05-07	2000-08-08
2001	2001-05-02	2001-08-16
2002	2002-04-16	2002-09-09
2003	2003-06-24	2003-08-30
2004	2004-06-09	2004-06-18
2005	2005-06-08	2005-09-23
2006	2006-07-04	2006-08-23
2007	2007-05-25	2007-10-08
2008	2008-06-08	2008-08-06
2009	2009-04-26	2009-08-26
2010	2010-05-26	2010-09-25
2011	2011-05-30	2011-08-26
2012	2012-06-20	2012-09-01
2013	2013-05-30	2013-09-11
2014	2014-05-26	2014-09-06
2015	2015-06-14	2015-09-09
2016	2016-05-25	2016-09-09
2017	2017-05-18	2017-09-27
2018	2018-06-02	2018-09-06
2019	2019-05-26	2019-10-02
2020	2020-06-22	2020-09-04
2021	2021-05-22	2021-08-31
2022	2022-05-21	2022-09-01
2023	2023-07-03	2023-09-07
2024	2024-06-21	2024-08-28
2025	2025-06-12	2025-08-17
2026	2026-05-20	2026-09-10

Every Fixed Threshold

Fixed thresholds at Islip-Li Macarthur AP
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	63	39	2010	19
35 C (95 F): Days	35	7	1999	3
40 C (104 F): Days	1	1	1966	1
90 F (32.2 C): Days	59	18	1999	9
100 F (37.8 C): Days	8	1	1966	1
0 C (32 F): Ice days (max	63	46	1978	22
0 C (32 F): Frost days (min	63	129	1967	67
-10 C (14 F): Days with min	63	36	1968	17
-20 C (-4 F): Days with min	7	2	1965	2
20 C (68 F): Tropical nights (min	63	55	2021	39
25 C (77 F): Days with min	18	4	1995	2
10 mm (0.39 in): Days with 10 mm or more rain	63	52	1983	28
25 mm (0.98 in): Days with 25 mm or more rain	63	26	2018	14
50 mm (1.97 in): Days with 50 mm or more rain	58	6	1990	5
100 mm (3.94 in): Days with 100 mm or more rain	16	1	1972	1
200 mm (7.87 in): Days with 200 mm or more rain	1	1	2014	1
10 cm (3.9 in): Days with 10 cm or more snowfall	53	8	1996	3
25 cm (9.8 in): Days with 25 cm or more snowfall	21	2	1967	2
50 cm (19.7 in): Days with 50 cm or more snowfall	2	1	2016	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.

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Data for Islip-Li Macarthur AP 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).

Islip-Li Macarthur AP Threshold Days by Year (USW00004781)

Key Facts for Islip-Li Macarthur AP Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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