San Antonio Cn Mouth Weather Records (USC00047711)

Record envelope, standing records and threshold days for San Antonio Cn Mouth (USC00047711), California, United States, with 51 years of record.

Key Facts for San Antonio Cn Mouth

San Antonio Cn Mouth (USC00047711) is a weather station in California, United States at 34.17 latitude and -117.67 longitude, 729 m (2,392 ft) above sea level.
The station reports from 1917 to 1967, 51 years of record.
1,464 records set at San Antonio Cn Mouth still stand.
Records are tracked for tmax, tmin, prcp: an element needs 30 years of data to be eligible.
San Antonio Cn Mouth set a daily record high minimum temperature of 24.4 C (75.9 F) on 31 August 1967.

About the Station

Location: California, United States, 34.17 latitude, -117.67 longitude.
Elevation: 729 m (2,392 ft).
Period of record: 1917 to 1967, 51 years.
Eligible elements: tmax, tmin, prcp.

Daily Record Envelope and 2026

0 days at or beyond a record

The band shows the record high and record low for each calendar day at San Antonio Cn Mouth. The lines show the 2026 daily maximum and minimum. 0 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.

Daily record high and record low at San Antonio Cn Mouth, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	30.0 C (86.0 F)	-6.7 C (19.9 F)	n/a	n/a
Feb	30.0 C (86.0 F)	-4.4 C (24.1 F)	n/a	n/a
Mar	33.3 C (91.9 F)	-2.8 C (27.0 F)	n/a	n/a
Apr	36.7 C (98.1 F)	-2.2 C (28.0 F)	n/a	n/a
May	39.4 C (102.9 F)	0.0 C (32.0 F)	n/a	n/a
Jun	42.2 C (108.0 F)	3.9 C (39.0 F)	n/a	n/a
Jul	46.7 C (116.1 F)	3.9 C (39.0 F)	n/a	n/a
Aug	46.7 C (116.1 F)	7.2 C (45.0 F)	n/a	n/a
Sep	43.3 C (109.9 F)	3.3 C (37.9 F)	n/a	n/a
Oct	39.4 C (102.9 F)	0.6 C (33.1 F)	n/a	n/a
Nov	35.0 C (95.0 F)	-2.2 C (28.0 F)	n/a	n/a
Dec	32.2 C (90.0 F)	-2.8 C (27.0 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at San Antonio Cn Mouth still stand. 1933 holds the most, with 120.

Standing records at San Antonio Cn Mouth by the year they were set
Year set	Standing records
1933	120
1934	51
1935	44
1936	78
1937	62
1938	54
1939	74
1940	44
1941	52
1942	26
1943	20
1944	34
1945	20
1946	15
1947	30
1948	35
1949	80
1950	52
1951	32
1952	30
1953	39
1954	39
1955	42
1956	44
1957	45
1958	23
1959	23
1960	33
1961	31
1962	39
1963	28
1964	37
1965	47
1966	21
1967	20

Wettest Day of Each Month

Mar: 258.3 mm (10.2 in)

The wettest day on record for each calendar month at San Antonio Cn Mouth. The most was 258.3 mm (10.2 in) on 3 March 1938.

Record daily precipitation for each month at San Antonio Cn Mouth
Month	Record daily precipitation (mm)	Date
Jan	255.3 mm (10.1 in)	22 January 1943
Feb	183.6 mm (7.2 in)	16 February 1927
Mar	258.3 mm (10.2 in)	3 March 1938
Apr	118.9 mm (4.7 in)	6 April 1926
May	56.4 mm (2.2 in)	21 May 1921
Jun	20.8 mm (0.8 in)	4 June 1925
Jul	9.1 mm (0.36 in)	25 July 1956
Aug	10.2 mm (0.4 in)	18 August 1945
Sep	152.9 mm (6.0 in)	25 September 1939
Oct	104.6 mm (4.1 in)	18 October 1934
Nov	124.7 mm (4.9 in)	12 November 1946
Dec	217.2 mm (8.6 in)	6 December 1966

Period of Record Coverage

1933 to 1967

35 years of record at San Antonio Cn Mouth, 1933 to 1967. 2 years have data for under 90 percent of days and are left out of rankings: 1938, 1967.

Days with data per year at San Antonio Cn Mouth
Year	Days with data	Share of year	Complete
1933	363	99%	Yes
1934	365	100%	Yes
1935	365	100%	Yes
1936	365	100%	Yes
1937	365	100%	Yes
1938	325	89%	No
1939	364	100%	Yes
1940	366	100%	Yes
1941	364	100%	Yes
1942	362	99%	Yes
1943	365	100%	Yes
1944	362	99%	Yes
1945	349	96%	Yes
1946	357	98%	Yes
1947	347	95%	Yes
1948	348	95%	Yes
1949	365	100%	Yes
1950	365	100%	Yes
1951	365	100%	Yes
1952	356	97%	Yes
1953	362	99%	Yes
1954	361	99%	Yes
1955	359	98%	Yes
1956	359	98%	Yes
1957	363	99%	Yes
1958	359	98%	Yes
1959	364	100%	Yes
1960	348	95%	Yes
1961	365	100%	Yes
1962	364	100%	Yes
1963	365	100%	Yes
1964	366	100%	Yes
1965	365	100%	Yes
1966	364	100%	Yes
1967	187	51%	No

Latest Records

Latest records at San Antonio Cn Mouth
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
31 August 1967	San Antonio Cn Mouth, US	daily high min	24.4 C (75.9 F)	0.5 C (0.9 F)	12 years	7 of 100 (Routine)
30 August 1967	San Antonio Cn Mouth, US	daily high min	25.6 C (78.1 F)	1.7 C (3.1 F)	12 years	11 of 100 (Routine)
29 August 1967	San Antonio Cn Mouth, US	daily high min	23.9 C (75.0 F)	0.6 C (1.1 F)	22 years	10 of 100 (Routine)
23 July 1967	San Antonio Cn Mouth, US	daily low min (Tie)	12.8 C (55.0 F)	tie	22 years	2 of 100 (Routine)
13 June 1967	San Antonio Cn Mouth, US	daily rain	4.1 mm (0.16 in)	2.8 mm (0.11 in)	8 years	13 of 100 (Routine)
1 June 1967	San Antonio Cn Mouth, US	daily rain	3.8 mm (0.15 in)	1.3 mm (0.05 in)	18 years	13 of 100 (Routine)
31 May 1967	San Antonio Cn Mouth, US	daily low min	2.8 C (37.0 F)	1.6 C (2.9 F)	32 years	16 of 100 (Routine)
31 May 1967	San Antonio Cn Mouth, US	daily low max	12.2 C (54.0 F)	2.8 C (5.0 F)	12 years	10 of 100 (Routine)
31 May 1967	San Antonio Cn Mouth, US	daily rain	5.8 mm (0.23 in)	4.8 mm (0.19 in)	1 year	9 of 100 (Routine)
29 May 1967	San Antonio Cn Mouth, US	daily low max	12.2 C (54.0 F)	1.1 C (2.0 F)	29 years	12 of 100 (Routine)
28 May 1967	San Antonio Cn Mouth, US	daily low max (Tie)	13.9 C (57.0 F)	tie	10 years	1 of 100 (Routine)
22 May 1967	San Antonio Cn Mouth, US	daily high max	37.8 C (100.0 F)	2.8 C (5.0 F)	30 years	16 of 100 (Routine)
21 May 1967	San Antonio Cn Mouth, US	daily high max	35.0 C (95.0 F)	1.1 C (2.0 F)	32 years	13 of 100 (Routine)
17 May 1967	San Antonio Cn Mouth, US	daily high max	34.4 C (93.9 F)	1.1 C (2.0 F)	10 years	7 of 100 (Routine)
1 May 1967	San Antonio Cn Mouth, US	daily low min	0.6 C (33.1 F)	2.2 C (4.0 F)	32 years	18 of 100 (Routine)
23 April 1967	San Antonio Cn Mouth, US	daily low min	1.7 C (35.1 F)	0.5 C (0.9 F)	6 years	6 of 100 (Routine)
22 April 1967	San Antonio Cn Mouth, US	daily rain	52.1 mm (2.1 in)	37.9 mm (1.5 in)	12 years	30 of 100 (Routine)
22 April 1967	San Antonio Cn Mouth, US	daily low min	2.2 C (36.0 F)	1.1 C (2.0 F)	4 years	6 of 100 (Routine)
20 April 1967	San Antonio Cn Mouth, US	daily low max	10.6 C (51.1 F)	1.1 C (2.0 F)	4 years	5 of 100 (Routine)
16 April 1967	San Antonio Cn Mouth, US	daily low min	1.7 C (35.1 F)	1.1 C (2.0 F)	26 years	13 of 100 (Routine)

Climate Trend

32 complete years, 1933 to 1966

One stripe for each of 32 complete years at San Antonio Cn Mouth, 1933 to 1966. Blue stripes are years cooler than the station's own mean of 17.3 C (63.1 F); red stripes are warmer. The coolest year was 1955, at 16.2 C (61.2 F), and the warmest was 1934, at 19.1 C (66.4 F). The strongest colour marks a difference of 1.9 C (3.4 F).

Annual mean temperature at San Antonio Cn Mouth as warming stripes, 1933 to 1966
Year	Annual mean temperature	Difference from the station mean
1933	17.8 C	+0.49 C
1934	19.1 C	+1.85 C
1935	17.3 C	+0.07 C
1936	18.6 C	+1.29 C
1937	17.6 C	+0.31 C
1939	18.2 C	+0.91 C
1940	18.2 C	+0.96 C
1941	17.0 C	-0.29 C
1942	17.0 C	-0.29 C
1943	17.8 C	+0.50 C
1944	16.3 C	-0.96 C
1945	16.8 C	-0.44 C
1946	17.0 C	-0.25 C
1947	17.6 C	+0.31 C
1948	16.8 C	-0.51 C
1949	16.6 C	-0.66 C
1950	17.6 C	+0.38 C
1951	16.7 C	-0.56 C
1952	16.6 C	-0.64 C
1953	17.2 C	-0.06 C
1954	17.3 C	+0.05 C
1955	16.2 C	-1.02 C
1956	16.9 C	-0.39 C
1957	16.5 C	-0.77 C
1958	17.7 C	+0.41 C
1959	17.9 C	+0.66 C
1961	17.5 C	+0.28 C
1962	17.2 C	-0.05 C
1963	16.8 C	-0.51 C
1964	16.6 C	-0.64 C
1965	16.6 C	-0.67 C
1966	17.6 C	+0.32 C

The annual mean temperature here has fallen by 0.3 C (0.1 to 0.5) per decade over 1933 to 1966. In Fahrenheit: 0.6 F (0.1 to 1.0) per decade. The slope is a straight line fitted to 32 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at San Antonio Cn Mouth
Measure	Per decade (C)	Per decade (F)	Period	Complete years	Reading
Annual mean temperature	-0.3 C (-0.5 to -0.1) per decade	-0.6 F (-1.0 to -0.1) per decade	1933 to 1966	32	Fall
Mean daily maximum	-0.8 C (-1.2 to -0.5) per decade	-1.5 F (-2.1 to -0.9) per decade	1933 to 1966	32	Fall
Mean daily minimum	0.21 C (-0.01 to 0.43) per decade	0.38 F (-0.01 to 0.77) per decade	1933 to 1966	32	Not clearly different from zero

A year is complete when all 12 months have at least 20 days of both daily maximum and daily minimum readings. The annual mean is the mean of the monthly means. The trend describes this one station over this period; it does not say what caused the change.

Extremes by Year

1917 to 1967

Yearly extremes at San Antonio Cn Mouth: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	46.7 C (116.1 F)	1933	40.0 C (104.0 F)	35
Coldest night (TNn)	-6.7 C (19.9 F)	1937	-1.1 C (30.0 F)	35
Wettest day (Rx1day)	258.3 mm (10.2 in)	1938	88.9 mm (3.5 in)	51
Wettest five days (Rx5day)	536.9 mm (21.1 in)	1966	160.8 mm (6.3 in)	51
Longest dry spell (CDD)	171 days	1954	101 days	51

Hottest day (TXx)

The hottest day of the year at San Antonio Cn Mouth, 1917 to 1967. The record is 46.7 C (116.1 F) in 1933, marked on the chart; the median year is 40.0 C (104.0 F).

Hottest day (TXx) at San Antonio Cn Mouth by year
Year	Hottest day (TXx)
1917	n/a
1918	n/a
1919	n/a
1920	n/a
1921	n/a
1922	n/a
1923	n/a
1924	n/a
1925	n/a
1926	n/a
1927	n/a
1928	n/a
1929	n/a
1930	n/a
1931	n/a
1932	n/a
1933	46.7 C (116.1 F)
1934	46.1 C (115.0 F)
1935	42.2 C (108.0 F)
1936	45.6 C (114.1 F)
1937	41.7 C (107.1 F)
1938	43.3 C (109.9 F)
1939	43.9 C (111.0 F)
1940	41.1 C (106.0 F)
1941	41.7 C (107.1 F)
1942	38.9 C (102.0 F)
1943	40.6 C (105.1 F)
1944	40.6 C (105.1 F)
1945	38.3 C (100.9 F)
1946	40.0 C (104.0 F)
1947	39.4 C (102.9 F)
1948	42.2 C (108.0 F)
1949	40.0 C (104.0 F)
1950	42.2 C (108.0 F)
1951	38.9 C (102.0 F)
1952	37.2 C (99.0 F)
1953	39.4 C (102.9 F)
1954	38.3 C (100.9 F)
1955	41.7 C (107.1 F)
1956	39.4 C (102.9 F)
1957	38.9 C (102.0 F)
1958	39.4 C (102.9 F)
1959	40.6 C (105.1 F)
1960	42.8 C (109.0 F)
1961	40.6 C (105.1 F)
1962	39.4 C (102.9 F)
1963	38.9 C (102.0 F)
1964	38.3 C (100.9 F)
1965	38.3 C (100.9 F)
1966	38.9 C (102.0 F)
1967	40.0 C (104.0 F)

Coldest night (TNn)

The coldest night of the year at San Antonio Cn Mouth, 1917 to 1967. The record is -6.7 C (19.9 F) in 1937, marked on the chart; the median year is -1.1 C (30.0 F).

Coldest night (TNn) at San Antonio Cn Mouth by year
Year	Coldest night (TNn)
1917	n/a
1918	n/a
1919	n/a
1920	n/a
1921	n/a
1922	n/a
1923	n/a
1924	n/a
1925	n/a
1926	n/a
1927	n/a
1928	n/a
1929	n/a
1930	n/a
1931	n/a
1932	n/a
1933	-3.3 C (26.1 F)
1934	0.6 C (33.1 F)
1935	-2.2 C (28.0 F)
1936	-2.8 C (27.0 F)
1937	-6.7 C (19.9 F)
1938	-0.6 C (30.9 F)
1939	-3.3 C (26.1 F)
1940	0.6 C (33.1 F)
1941	-1.7 C (28.9 F)
1942	-2.2 C (28.0 F)
1943	-0.6 C (30.9 F)
1944	0.0 C (32.0 F)
1945	-0.6 C (30.9 F)
1946	-0.6 C (30.9 F)
1947	0.0 C (32.0 F)
1948	-2.8 C (27.0 F)
1949	-5.0 C (23.0 F)
1950	-2.8 C (27.0 F)
1951	-1.7 C (28.9 F)
1952	-1.7 C (28.9 F)
1953	-1.1 C (30.0 F)
1954	-1.1 C (30.0 F)
1955	-1.1 C (30.0 F)
1956	-1.7 C (28.9 F)
1957	-3.9 C (25.0 F)
1958	0.6 C (33.1 F)
1959	-1.1 C (30.0 F)
1960	-1.1 C (30.0 F)
1961	1.7 C (35.1 F)
1962	-2.2 C (28.0 F)
1963	-1.7 C (28.9 F)
1964	-1.1 C (30.0 F)
1965	-1.7 C (28.9 F)
1966	-0.6 C (30.9 F)
1967	-0.6 C (30.9 F)

Wettest day (Rx1day)

The wettest day of the year at San Antonio Cn Mouth, 1917 to 1967. The record is 258.3 mm (10.2 in) in 1938, marked on the chart; the median year is 88.9 mm (3.5 in).

Wettest day (Rx1day) at San Antonio Cn Mouth by year
Year	Wettest day (Rx1day)
1917	44.7 mm (1.8 in)
1918	88.9 mm (3.5 in)
1919	57.9 mm (2.3 in)
1920	58.7 mm (2.3 in)
1921	135.9 mm (5.4 in)
1922	100.8 mm (4.0 in)
1923	54.1 mm (2.1 in)
1924	66.0 mm (2.6 in)
1925	60.2 mm (2.4 in)
1926	118.9 mm (4.7 in)
1927	183.6 mm (7.2 in)
1928	64.3 mm (2.5 in)
1929	75.7 mm (3.0 in)
1930	61.5 mm (2.4 in)
1931	109.2 mm (4.3 in)
1932	94.5 mm (3.7 in)
1933	129.3 mm (5.1 in)
1934	128.0 mm (5.0 in)
1935	78.5 mm (3.1 in)
1936	87.9 mm (3.5 in)
1937	86.6 mm (3.4 in)
1938	258.3 mm (10.2 in)
1939	152.9 mm (6.0 in)
1940	115.3 mm (4.5 in)
1941	97.8 mm (3.9 in)
1942	33.8 mm (1.3 in)
1943	255.3 mm (10.1 in)
1944	147.3 mm (5.8 in)
1945	178.8 mm (7.0 in)
1946	124.7 mm (4.9 in)
1947	40.6 mm (1.6 in)
1948	58.4 mm (2.3 in)
1949	111.3 mm (4.4 in)
1950	58.4 mm (2.3 in)
1951	72.4 mm (2.9 in)
1952	109.2 mm (4.3 in)
1953	43.2 mm (1.7 in)
1954	158.8 mm (6.3 in)
1955	45.0 mm (1.8 in)
1956	202.2 mm (8.0 in)
1957	74.7 mm (2.9 in)
1958	95.5 mm (3.8 in)
1959	68.8 mm (2.7 in)
1960	37.8 mm (1.5 in)
1961	78.2 mm (3.1 in)
1962	80.0 mm (3.1 in)
1963	127.8 mm (5.0 in)
1964	53.3 mm (2.1 in)
1965	95.0 mm (3.7 in)
1966	217.2 mm (8.6 in)
1967	93.5 mm (3.7 in)

Wettest five days (Rx5day)

The wettest five days of the year at San Antonio Cn Mouth, 1917 to 1967. The record is 536.9 mm (21.1 in) in 1966, marked on the chart; the median year is 160.8 mm (6.3 in).

Wettest five days (Rx5day) at San Antonio Cn Mouth by year
Year	Wettest five days (Rx5day)
1917	57.9 mm (2.3 in)
1918	188.5 mm (7.4 in)
1919	69.9 mm (2.8 in)
1920	133.8 mm (5.3 in)
1921	221.0 mm (8.7 in)
1922	168.2 mm (6.6 in)
1923	54.1 mm (2.1 in)
1924	125.9 mm (5.0 in)
1925	94.2 mm (3.7 in)
1926	261.9 mm (10.3 in)
1927	351.5 mm (13.8 in)
1928	100.1 mm (3.9 in)
1929	86.9 mm (3.4 in)
1930	134.0 mm (5.3 in)
1931	183.8 mm (7.2 in)
1932	158.2 mm (6.2 in)
1933	230.2 mm (9.1 in)
1934	248.7 mm (9.8 in)
1935	100.1 mm (3.9 in)
1936	202.2 mm (8.0 in)
1937	138.4 mm (5.4 in)
1938	184.6 mm (7.3 in)
1939	185.4 mm (7.3 in)
1940	143.0 mm (5.6 in)
1941	183.1 mm (7.2 in)
1942	60.3 mm (2.4 in)
1943	503.7 mm (19.8 in)
1944	269.2 mm (10.6 in)
1945	330.9 mm (13.0 in)
1946	231.6 mm (9.1 in)
1947	70.1 mm (2.8 in)
1948	83.6 mm (3.3 in)
1949	160.8 mm (6.3 in)
1950	67.8 mm (2.7 in)
1951	151.2 mm (6.0 in)
1952	180.1 mm (7.1 in)
1953	43.2 mm (1.7 in)
1954	189.0 mm (7.4 in)
1955	71.9 mm (2.8 in)
1956	283.2 mm (11.1 in)
1957	162.9 mm (6.4 in)
1958	166.5 mm (6.6 in)
1959	105.9 mm (4.2 in)
1960	69.1 mm (2.7 in)
1961	90.1 mm (3.5 in)
1962	170.7 mm (6.7 in)
1963	143.3 mm (5.6 in)
1964	81.1 mm (3.2 in)
1965	244.1 mm (9.6 in)
1966	536.9 mm (21.1 in)
1967	186.2 mm (7.3 in)

Longest dry spell (CDD)

The longest dry spell of the year at San Antonio Cn Mouth, 1917 to 1967. The record is 171 days in 1954, marked on the chart; the median year is 101 days.

Longest dry spell (CDD) at San Antonio Cn Mouth by year
Year	Longest dry spell (CDD)
1917	101 days
1918	56 days
1919	57 days
1920	117 days
1921	129 days
1922	101 days
1923	73 days
1924	132 days
1925	100 days
1926	148 days
1927	136 days
1928	46 days
1929	104 days
1930	134 days
1931	77 days
1932	119 days
1933	56 days
1934	25 days
1935	29 days
1936	26 days
1937	31 days
1938	137 days
1939	43 days
1940	27 days
1941	34 days
1942	102 days
1943	75 days
1944	151 days
1945	112 days
1946	51 days
1947	105 days
1948	136 days
1949	141 days
1950	111 days
1951	136 days
1952	132 days
1953	147 days
1954	171 days
1955	171 days
1956	70 days
1957	122 days
1958	94 days
1959	91 days
1960	128 days
1961	89 days
1962	111 days
1963	74 days
1964	93 days
1965	55 days
1966	131 days
1967	79 days

Each chart shows one value per year; the dot marks the record year. TXx is the hottest daily maximum, TNn the coldest daily minimum, Rx1day and Rx5day the largest one-day and five-day rain totals, and CDD the longest run of days with less than 1 mm of rain. A year with missing days can understate an extreme.

Rainfall Return Levels

37 years, 1919 to 1966

A day with at least 83.0 mm (3.3 in) of rain is expected about once in 2 years. A day with at least 277.2 mm (10.9 in) of rain is expected about once in 100 years.

Rainfall return levels at San Antonio Cn Mouth: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	83.0 mm (3.3 in)
5 years	125.8 mm (5.0 in)
10 years	157.5 mm (6.2 in)
25 years	201.8 mm (7.9 in)
50 years	238.1 mm (9.4 in)	Longer than the 37 years of record
100 years	277.2 mm (10.9 in)	Longer than the 37 years of record

The levels come from a generalised extreme value (GEV) distribution fitted by L-moments to the wettest-day total of each year, 37 years of values from 1919 to 1966.

A return level is an estimate. It is least reliable for the long periods, 50 and 100 years, and for any period longer than the record behind the fit, where the fit has to reach past the largest day actually observed. It is not a forecast.

The largest wettest-day totals in the fit: 217.2 mm (8.6 in) in 1966; 202.2 mm (8.0 in) in 1956; 183.6 mm (7.2 in) in 1927.

Download the Data

Data for San Antonio Cn Mouth standing records by year: CSV or JSON. Field meanings are on the data page.
Data for San Antonio Cn Mouth 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 2026-10-14 (14 October 2026). Records are computed by this site and are not official.

Data as of 2025-12-31. Last revised 31 December 2025 (2025-12-31).