Islip, NY: December

31 December 2025: December 2025 averaged 34.3°F in Islip, NY, the coldest December since 2017, 20th coldest of 63.

December 2025

Mean temperature: 34.3°F; Coldest since 2017; 20th coldest of 63
Precipitation: 3.77 in; Driest since 2021; 27th driest of 63

A normal December in Islip, NY (1991 to 2020): a mean temperature of 37°F, between 33.3°F and 40.6°F in eight years of ten and 4.59 in of precipitation, between 2.15 in and 6.81 in in eight years of ten.

The mean temperature of every December in Islip, NY since 1963: 34.3°F in 2025; the lowest is 24.8°F, in 1989.

Normal range, 33.3 to 40.6°F

Every year, ranked, as a table

Every December in Islip, NY from 1963 to 2025, ranked: the mean temperature, the mean high and the mean low from the warmest, the precipitation from the wettest; a year missing more than a tenth of its days is not ranked.

Year	Mean, °F	Rank	High, °F	Rank	Low, °F	Rank	Precipitation, in	Rank	Days missing
2025	34.3	44	42.1	41	26.5	50	3.77	37	0
2024	36.5	33	44.4	29	28.7	35	6.23	12	0
2023	42.2	2	49.1	4	35.4	2	8.56	3	0
2022	36.8	27	44.7	25	29	31	4.42	33	0
2021	41.7	3	48.7	8	34.7	3	1.37	60	0
2020	37.2	23	44.9	23	29.4	26	4.50	32	0
2019	36.8	27	44.2	31	29.5	25	8.01	5	0
2018	38.1	20	45.6	20	30.6	18	6.50	10	0
2017	33.8	46	40.5	51	27	45	2.12	55	0
2016	36.6	31	44.8	24	28.4	37	3.53	39	0
2015	48.4	1	55.7	1	41.1	1	5.33	21	0
2014	39.6	14	45.8	18	33.4	7	6.12	13	0
2013	37.1	24	44.5	27	29.7	23	5.80	18	0
2012	40.5	7	47.5	11	33.5	6	6.12	13	0
2011	40.5	7	49.4	2	31.6	15	2.94	46	0
2010	31.5	57	37.7	58	25.2	54	4.54	31	0
2009	34.5	43	41.9	44	27.1	43	8.82	2	0
2008	36.7	30	44.5	27	29	31	6.68	9	0
2007	35.1	42	42.3	39	27.9	40	4.64	30	0
2006	41.1	6	49	6	33.2	9	2.15	53	0
2005	33.5	48	40.4	53	26.7	47	2.95	45	0
2004	35.2	39	43.4	37	27.1	43	3.06	41	0
2003	36.6	31	44	33	29.2	28	3.80	36	0
2002	33.5	48	41.1	47	25.8	51	5.02	23	0
2001	41.2	4	49.4	2	33.1	10	2.15	53	0
2000	29.6	59	37	61	22.2	59	2.97	43	0
1999	38.3	19	46.4	15	30.3	19	2.60	49	0
1998	40	11	48.9	7	31	17	1.72	58	0
1997	37.7	21	45.5	21	29.9	21	5.23	22	0
1996	39	17	46	17	32.1	13	8.91	1	0
1995	31.4	58	38.6	57	24.2	57	4.05	35	0
1994	39.7	13	48.1	9	31.4	16	3.73	38	0
1993	35.2	39	42.3	39	28	38	4.65	28	0
1992	36.1	35	43.7	35	28.5	36	6.06	16	0
1991	37.3	22	45.7	19	28.9	33	4.96	24	0
1990	39.9	12	48	10	31.8	14	4.65	28	0
1989	24.8	63	32.3	63	17.2	63	0.97	62	0
1988	33.4	51	41	49	25.7	52	2.96	44	0
1987	36.8	27	44.4	29	29.3	27	2.94	46	0
1986	36.4	34	43.6	36	29.2	28	5.46	19	0
1985	32.1	56	40	54	24.2	57	0.90	63	0
1984	41.2	4	49.1	4	33.4	7	2.33	50	0
1983	33.6	47	40.5	51	26.7	47	4.89	27	0
1982	40.1	9	46.6	14	33.6	5	2.08	56	0
1981	36.1	35	42.1	41	30.2	20	4.92	26	0
1980	33.5	48	41.7	45	25.3	53	1.05	61	0
1979	39.1	16	46.1	16	32.2	12	3.01	42	0
1978	36.9	25	44	33	29.7	23	6.07	15	0
1977	32.8	55	38.9	56	26.7	47	7.58	6	0
1976	28.9	61	37.7	58	20	62	2.16	52	0
1975	35.2	39	43.2	38	27.2	42	4.32	34	0
1974	36.9	25	44.7	25	29.1	30	6.78	8	0
1973	38.4	18	47.1	13	29.8	22	8.26	4	0
1972	39.6	14	45.5	21	33.8	4	4.93	25	0
1971	40.1	9	47.3	12	32.9	11	2.67	48	0
1970	34	45	41.1	47	27	45	3.37	40	0
1969	33.4	51	39.4	55	27.4	41	7.28	7	0
1968	29.3	60	37.3	60	21.3	60	5.35	20	0
1967	33.1	53	41	49	25.1	55	6.32	11	0
1966	33	54	41.3	46	24.7	56	1.98	57	0
1965	36	37	44.1	32	28	38	1.57	59	0
1964	35.5	38	42.1	41	28.8	34	5.96	17	0
1963	28.1	62	35.6	62	20.6	61	2.21	51	2

Warmest, coldest, wettest and driest

Warmest
Year	Mean, °F
2015	48.4
2023	42.2
2021	41.7
2001	41.2
1984	41.2
2006	41.1
2012	40.5
2011	40.5
1982	40.1
1971	40.1

Coldest
Year	Mean, °F
1989	24.8
1963	28.1
1976	28.9
1968	29.3
2000	29.6
1995	31.4
2010	31.5
1985	32.1
1977	32.8
1966	33

Wettest
Year	Precipitation, in
1996	8.91
2009	8.82
2023	8.56
1973	8.26
2019	8.01
1977	7.58
1969	7.28
1974	6.78
2008	6.68
2018	6.50

Driest
Year	Precipitation, in
1985	0.90
1989	0.97
1980	1.05
2021	1.37
1965	1.57
1998	1.72
1966	1.98
1982	2.08
2017	2.12
2006	2.15
More years share the last value

The hottest, coldest and wettest days

Hottest day: 59°F; 19 December 2025
Coldest night: 16°F; 28 December 2025
Wettest day: 1.33 in; 2 December 2025

Every month, season and year

Months

Seasons

Years

Islip, NY the day's answers

All-time records

Every answer in words

December 2025 brought 3.77 in of precipitation in Islip, NY, the driest December since 2021, 27th driest of 63.
The hottest day of December 2025 in Islip, NY: 59°F on Friday 19 December 2025.
The coldest night of December 2025 in Islip, NY: a low of 16°F on Sunday 28 December 2025.
The wettest day of December 2025 in Islip, NY: 1.33 in on Tuesday 2 December 2025.