Grannis Threshold Days by Year (USC00032908)

19 fixed thresholds counted per year at Grannis (USC00032908): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Grannis Thresholds

Grannis: nights with a minimum temperature at or below 0 C (32 F) in 33 years, most in 1929 with 87.
Grannis: nights with a minimum temperature at or above 20 C (68 F) in 33 years, most in 1951 with 74.
Grannis: days with 10 mm (0.39 in) or more of precipitation in 33 years, most in 1923 with 58.
Grannis: days with 25 mm (0.98 in) or more of precipitation in 33 years, most in 1935 with 28.
19 fixed thresholds have at least one qualifying day at Grannis.

Days at or above 30 C (86 F)

32 years with a qualifying day

Days per year at Grannis with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 126 in 1956.

Days at or above 30 C (86 F) per year at Grannis
Year	Days	Decade average
1920	87	95.7
1921	100	95.7
1922	94	95.7
1923	85	95.7
1924	88	95.7
1925	121	95.7
1929	95	95.7
1931	124	113.6
1932	113	113.6
1933	114	113.6
1934	125	113.6
1935	95	113.6
1936	118	113.6
1937	97	113.6
1939	123	113.6
1940	77	94.8
1941	110	94.8
1942	95	94.8
1943	114	94.8
1944	115	94.8
1945	84	94.8
1946	90	94.8
1947	92	94.8
1948	97	94.8
1949	74	94.8
1950	35	97.1
1951	91	97.1
1952	116	97.1
1953	118	97.1
1954	111	97.1
1955	83	97.1
1956	126	97.1

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

First to last qualifying date each year at Grannis
Year	First date	Last date
1920	1920-04-17	1920-10-05
1921	1921-05-12	1921-10-19
1922	1922-05-06	1922-10-05
1923	1923-04-24	1923-10-02
1924	1924-04-15	1924-10-05
1925	1925-04-17	1925-10-21
1929	1929-03-23	1929-10-19
1931	1931-05-25	1931-11-03
1932	1932-02-28	1932-09-27
1933	1933-05-08	1933-09-30
1934	1934-05-07	1934-10-27
1935	1935-05-12	1935-10-16
1936	1936-04-01	1936-09-23
1937	1937-04-15	1937-10-30
1939	1939-04-26	1939-10-27
1940	1940-04-03	1940-10-23
1941	1941-05-08	1941-10-24
1942	1942-04-04	1942-09-19
1943	1943-04-30	1943-10-29
1944	1944-05-12	1944-10-29
1945	1945-05-07	1945-10-13
1946	1946-03-30	1946-10-09
1947	1947-05-04	1947-10-15
1948	1948-04-07	1948-09-23
1949	1949-05-26	1949-09-18
1950	1950-06-13	1950-09-21
1951	1951-05-20	1951-10-04
1952	1952-04-30	1952-10-05
1953	1953-05-21	1953-10-20
1954	1954-06-08	1954-10-06
1955	1955-03-11	1955-09-29
1956	1956-05-07	1956-10-16

Every Fixed Threshold

Fixed thresholds at Grannis
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	32	126	1956	126
35 C (95 F): Days	31	81	1934	49
40 C (104 F): Days	13	14	1934	8
45 C (113 F): Days	1	1	1936	1
90 F (32.2 C): Days	32	102	1934	94
100 F (37.8 C): Days	23	43	1934	17
110 F (43.3 C): Days	3	1	1935	1
0 C (32 F): Ice days (max	24	9	1948	1
0 C (32 F): Frost days (min	33	87	1929	48
-10 C (14 F): Days with min	29	15	1929	5
-20 C (-4 F): Days with min	2	1	1940	1
20 C (68 F): Tropical nights (min	33	74	1951	45
25 C (77 F): Days with min	9	7	1925	2
10 mm (0.39 in): Days with 10 mm or more rain	33	58	1923	22
25 mm (0.98 in): Days with 25 mm or more rain	33	28	1935	7
50 mm (1.97 in): Days with 50 mm or more rain	33	10	1921	1
100 mm (3.94 in): Days with 100 mm or more rain	18	2	1925	1
200 mm (7.87 in): Days with 200 mm or more rain	1	1	1947	1
10 cm (3.9 in): Days with 10 cm or more snowfall	5	2	1921	2

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1920.

Download the Data

Data for Grannis 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).

Grannis Threshold Days by Year (USC00032908)

Key Facts for Grannis Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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