San Jacinto Threshold Days by Year (USC00267284)

16 fixed thresholds counted per year at San Jacinto (USC00267284): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for San Jacinto Thresholds

San Jacinto: days with a maximum temperature at or above 30 C (86 F) in 24 years, most in 1940 with 77.
San Jacinto: days with a maximum temperature at or above 90 F (32.2 C) in 24 years, most in 1940 with 54.
San Jacinto: days with a maximum temperature at or below 0 C (32 F) in 24 years, most in 1928 with 47.
San Jacinto: days with 10 mm (0.39 in) or more of precipitation in 23 years, most in 1907 with 15.
16 fixed thresholds have at least one qualifying day at San Jacinto.

Days at or above 30 C (86 F)

24 years with a qualifying day

Days per year at San Jacinto with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 77 in 1940.

Days at or above 30 C (86 F) per year at San Jacinto
Year	Days	Decade average
1905	65	47.3
1906	48	47.3
1907	32	47.3
1908	44	47.3
1910	37	37.2
1911	31	37.2
1916	41	37.2
1917	37	37.2
1918	23	37.2
1919	54	37.2
1920	36	33.9
1921	38	33.9
1922	48	33.9
1923	44	33.9
1925	21	33.9
1926	37	33.9
1928	13	33.9
1937	68	63
1938	56	63
1939	65	63
1940	77	64.5
1943	62	64.5
1946	51	64.5
1947	68	64.5

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

First to last qualifying date each year at San Jacinto
Year	First date	Last date
1905	1905-06-11	1905-09-23
1906	1906-06-11	1906-09-06
1907	1907-07-02	1907-08-25
1908	1908-06-25	1908-09-06
1910	1910-05-30	1910-09-27
1911	1911-06-11	1911-09-01
1916	1916-06-16	1916-09-30
1917	1917-06-15	1917-09-19
1918	1918-06-08	1918-09-20
1919	1919-05-28	1919-08-30
1920	1920-07-07	1920-08-24
1921	1921-06-12	1921-10-04
1922	1922-06-17	1922-10-10
1923	1923-06-28	1923-09-15
1925	1925-06-20	1925-08-21
1926	1926-06-06	1926-08-28
1928	1928-07-08	1928-09-06
1937	1937-06-21	1937-09-19
1938	1938-05-26	1938-09-27
1939	1939-05-29	1939-09-21
1940	1940-06-11	1940-09-11
1943	1943-06-28	1943-09-24
1946	1946-06-04	1946-09-25
1947	1947-05-02	1947-09-25

Every Fixed Threshold

Fixed thresholds at San Jacinto
Threshold	Years with a qualifying day	Most days in a year	Year	Latest year days
30 C (86 F): Days	24	77	1940	68
35 C (95 F): Days	19	23	1940	10
40 C (104 F): Days	1	1	1940	1
90 F (32.2 C): Days	24	54	1940	39
100 F (37.8 C): Days	5	4	1940	4
0 C (32 F): Ice days (max	24	47	1928	19
0 C (32 F): Frost days (min	21	237	1920	203
-10 C (14 F): Days with min	21	91	1905	40
-20 C (-4 F): Days with min	20	26	1922	10
-30 C (-22 F): Days with min	7	8	1937	8
-40 C (-40 F): Days with min	1	2	1937	2
20 C (68 F): Tropical nights (min	1	1	1940	1
10 mm (0.39 in): Days with 10 mm or more rain	23	15	1907	5
25 mm (0.98 in): Days with 25 mm or more rain	6	2	1905	2
10 cm (3.9 in): Days with 10 cm or more snowfall	9	7	1906	2
25 cm (9.8 in): Days with 25 cm or more snowfall	1	1	1916	1

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1905.

Download the Data

Data for San Jacinto 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).

San Jacinto Threshold Days by Year (USC00267284)

Key Facts for San Jacinto Thresholds

Days at or above 30 C (86 F)

Every Fixed Threshold

Download the Data

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