Glen Lyn Threshold Days by Year (USC00443397)

15 fixed thresholds counted per year at Glen Lyn (USC00443397): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Glen Lyn Thresholds

Glen Lyn: days with 10 mm (0.39 in) or more of precipitation in 80 years, most in 2003 with 54.
Glen Lyn: days with 25 mm (0.98 in) or more of precipitation in 80 years, most in 1935 with 18.
Glen Lyn: days with 50 mm (1.97 in) or more of precipitation in 45 years, most in 2001 with 4.
Glen Lyn: nights with a minimum temperature at or below 0 C (32 F) in 38 years, most in 1941 with 135.
15 fixed thresholds have at least one qualifying day at Glen Lyn.

Days at or above 30 C (86 F)

37 years with a qualifying day

Days per year at Glen Lyn with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 116 in 1941.

Days at or above 30 C (86 F) per year at Glen Lyn
Year	Days	Decade average
1932	68	69.5
1933	77	69.5
1934	73	69.5
1935	48	69.5
1936	78	69.5
1937	49	69.5
1938	62	69.5
1939	101	69.5
1940	47	64
1941	116	64
1942	78	64
1943	80	64
1944	69	64
1945	68	64
1946	39	64
1947	54	64
1948	41	64
1949	48	64
1950	32	79.2
1951	71	79.2
1952	76	79.2
1953	92	79.2
1954	83	79.2
1955	90	79.2
1956	85	79.2
1957	86	79.2
1958	74	79.2
1959	103	79.2
1960	83	67.2
1961	66	67.2
1962	68	67.2
1963	54	67.2
1964	85	67.2
1965	78	67.2
1966	67	67.2
1967	47	67.2
1968	57	67.2

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

First to last qualifying date each year at Glen Lyn
Year	First date	Last date
1932	1932-05-05	1932-09-19
1933	1933-05-11	1933-10-01
1934	1934-05-05	1934-08-25
1935	1935-04-27	1935-08-26
1936	1936-05-02	1936-09-13
1937	1937-04-18	1937-09-04
1938	1938-05-03	1938-10-19
1939	1939-04-24	1939-10-10
1940	1940-05-06	1940-09-21
1941	1941-04-13	1941-10-20
1942	1942-04-05	1942-11-21
1943	1943-05-06	1943-09-15
1944	1944-05-03	1944-10-07
1945	1945-03-16	1945-09-28
1946	1946-04-22	1946-09-10
1947	1947-05-16	1947-09-20
1948	1948-05-10	1948-09-22
1949	1949-05-06	1949-10-10
1950	1950-04-29	1950-09-04
1951	1951-05-16	1951-10-07
1952	1952-04-22	1952-10-01
1953	1953-05-02	1953-10-05
1954	1954-03-25	1954-10-11
1955	1955-04-18	1955-10-07
1956	1956-04-29	1956-09-24
1957	1957-04-20	1957-09-23
1958	1958-05-03	1958-09-27
1959	1959-04-08	1959-10-07
1960	1960-04-14	1960-09-19
1961	1961-04-25	1961-09-26
1962	1962-04-26	1962-09-15
1963	1963-04-02	1963-09-21
1964	1964-04-21	1964-09-12
1965	1965-05-01	1965-09-22
1966	1966-05-06	1966-09-03
1967	1967-04-06	1967-08-19
1968	1968-05-15	1968-09-24

Every Fixed Threshold

Fixed thresholds at Glen Lyn
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	37	116	1941	57
35 C (95 F): Days	27	14	1934	3
90 F (32.2 C): Days	37	58	1941	27
100 F (37.8 C): Days	5	3	1934	1
0 C (32 F): Ice days (max	37	17	1958	16
0 C (32 F): Frost days (min	38	135	1941	113
-10 C (14 F): Days with min	38	34	1963	14
-20 C (-4 F): Days with min	7	3	1962	3
20 C (68 F): Tropical nights (min	37	23	1949	6
10 mm (0.39 in): Days with 10 mm or more rain	80	54	2003	23
25 mm (0.98 in): Days with 25 mm or more rain	80	18	1935	7
50 mm (1.97 in): Days with 50 mm or more rain	45	4	2001	2
100 mm (3.94 in): Days with 100 mm or more rain	2	1	1929	1
10 cm (3.9 in): Days with 10 cm or more snowfall	27	5	1947	1
25 cm (9.8 in): Days with 25 cm or more snowfall	7	1	1934	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1932.

Download the Data

Data for Glen Lyn 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).

Glen Lyn Threshold Days by Year (USC00443397)

Key Facts for Glen Lyn Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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