San Isidro Weather Records (MXN00004030)

Record envelope, standing records and threshold days for San Isidro (MXN00004030), Mexico, with 54 years of record.

Key Facts for San Isidro

San Isidro (MXN00004030) is a weather station in Mexico at 18.62 latitude and -91.05 longitude, 10 m (32 ft) above sea level.
The station reports from 1958 to 2011, 54 years of record.
1,464 records set at San Isidro still stand.
Records are tracked for tmax, tmin, prcp: an element needs 30 years of data to be eligible.
San Isidro set a daily record high maximum temperature of 36.7 C (98.1 F) on 30 December 2011.

About the Station

Location: Mexico, 18.62 latitude, -91.05 longitude.
Elevation: 10 m (32 ft).
Period of record: 1958 to 2011, 54 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 Isidro. 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 Isidro, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	37.8 C (100.0 F)	5.6 C (42.1 F)	n/a	n/a
Feb	40.0 C (104.0 F)	5.6 C (42.1 F)	n/a	n/a
Mar	41.7 C (107.1 F)	6.7 C (44.1 F)	n/a	n/a
Apr	45.0 C (113.0 F)	9.4 C (48.9 F)	n/a	n/a
May	45.6 C (114.1 F)	8.9 C (48.0 F)	n/a	n/a
Jun	42.8 C (109.0 F)	10.0 C (50.0 F)	n/a	n/a
Jul	40.0 C (104.0 F)	15.0 C (59.0 F)	n/a	n/a
Aug	40.6 C (105.1 F)	12.8 C (55.0 F)	n/a	n/a
Sep	41.7 C (107.1 F)	13.9 C (57.0 F)	n/a	n/a
Oct	41.7 C (107.1 F)	7.8 C (46.0 F)	n/a	n/a
Nov	41.7 C (107.1 F)	7.8 C (46.0 F)	n/a	n/a
Dec	37.8 C (100.0 F)	6.7 C (44.1 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at San Isidro still stand. 2009 holds the most, with 143.

Standing records at San Isidro by the year they were set
Year set	Standing records
1958	15
1959	32
1960	35
1961	28
1962	15
1963	41
1964	32
1965	18
1966	13
1967	30
1968	35
1969	14
1970	20
1971	31
1972	16
1973	41
1974	39
1975	4
1976	19
1977	22
1978	11
1979	15
1980	23
1981	18
1982	9
1983	25
1984	20
1985	9
1986	11
1987	15
1988	58
1990	47
1991	22
1992	25
1993	6
1994	6
1995	30
1996	58
2003	32
2004	24
2005	61
2006	47
2007	113
2008	62
2009	143
2010	24
2011	50

All-Time Record Progression

4 new records

4 all-time records were set at San Isidro between 2 October 1992 and 22 May 2009. Each dot is a new record.

When San Isidro set new all-time records
Date	Kind	Detail
1992-10-02	Record daily precipitation	Record daily precipitation 220.0 mm (8.7 in)
1995-10-10	Record daily precipitation	Record daily precipitation 275.8 mm (10.9 in)
2009-04-18	Record high maximum temperature	Record high maximum temperature 45.0 C (113.0 F)
2009-05-22	Record high maximum temperature	Record high maximum temperature 45.6 C (114.1 F)

Wettest Day of Each Month

Oct: 275.8 mm (10.9 in)

The wettest day on record for each calendar month at San Isidro. The most was 275.8 mm (10.9 in) on 10 October 1995.

Record daily precipitation for each month at San Isidro
Month	Record daily precipitation (mm)	Date
Jan	72.1 mm (2.8 in)	3 January 1983
Feb	64.8 mm (2.6 in)	26 February 2008
Mar	74.9 mm (2.9 in)	24 March 1966
Apr	80.8 mm (3.2 in)	8 April 1974
May	111.3 mm (4.4 in)	16 May 1974
Jun	127.8 mm (5.0 in)	27 June 1983
Jul	110.0 mm (4.3 in)	22 July 2010
Aug	159.8 mm (6.3 in)	21 August 2007
Sep	143.8 mm (5.7 in)	15 September 2010
Oct	275.8 mm (10.9 in)	10 October 1995
Nov	87.9 mm (3.5 in)	26 November 1992
Dec	86.6 mm (3.4 in)	15 December 1972

Period of Record Coverage

1958 to 2011

47 years of record at San Isidro, 1958 to 2011. 13 years have data for under 90 percent of days and are left out of rankings: 1958, 1984, 1986, 1987, 1988, 1990, 1991, 1992 and others.

Days with data per year at San Isidro
Year	Days with data	Share of year	Complete
1958	264	72%	No
1959	365	100%	Yes
1960	366	100%	Yes
1961	365	100%	Yes
1962	365	100%	Yes
1963	365	100%	Yes
1964	366	100%	Yes
1965	364	100%	Yes
1966	365	100%	Yes
1967	364	100%	Yes
1968	366	100%	Yes
1969	364	100%	Yes
1970	363	99%	Yes
1971	365	100%	Yes
1972	366	100%	Yes
1973	365	100%	Yes
1974	362	99%	Yes
1975	365	100%	Yes
1976	365	100%	Yes
1977	365	100%	Yes
1978	365	100%	Yes
1979	365	100%	Yes
1980	366	100%	Yes
1981	333	91%	Yes
1982	334	92%	Yes
1983	363	99%	Yes
1984	274	75%	No
1985	334	92%	Yes
1986	212	58%	No
1987	123	34%	No
1988	214	58%	No
1990	120	33%	No
1991	61	17%	No
1992	242	66%	No
1993	151	41%	No
1994	211	58%	No
1995	365	100%	Yes
1996	366	100%	Yes
2003	214	59%	No
2004	366	100%	Yes
2005	362	99%	Yes
2006	365	100%	Yes
2007	363	99%	Yes
2008	328	90%	No
2009	353	97%	Yes
2010	364	100%	Yes
2011	296	81%	No

Latest Records

Latest records at San Isidro
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
30 December 2011	San Isidro, MX	daily high max	36.7 C (98.1 F)	1.7 C (3.1 F)	2 years	10 of 100 (Routine)
29 December 2011	San Isidro, MX	daily high min	21.7 C (71.1 F)	1.1 C (2.0 F)	8 years	10 of 100 (Routine)
27 December 2011	San Isidro, MX	daily high min (Tie)	20.6 C (69.1 F)	tie	14 years	2 of 100 (Routine)
26 December 2011	San Isidro, MX	daily high max	35.0 C (95.0 F)	1.1 C (2.0 F)	0 years	8 of 100 (Routine)
25 December 2011	San Isidro, MX	daily high min	22.8 C (73.0 F)	2.2 C (4.0 F)	40 years	23 of 100 (Routine)
23 December 2011	San Isidro, MX	daily high min (Tie)	20.0 C (68.0 F)	tie	44 years	4 of 100 (Routine)
22 December 2011	San Isidro, MX	monthly high max (Tie)	37.8 C (100.0 F)	tie	15 years	4 of 100 (Routine)
19 December 2011	San Isidro, MX	daily high min	23.9 C (75.0 F)	3.3 C (5.9 F)	6 years	16 of 100 (Routine)
18 December 2011	San Isidro, MX	daily high max (Tie)	35.0 C (95.0 F)	tie	14 years	2 of 100 (Routine)
17 December 2011	San Isidro, MX	daily high max	36.7 C (98.1 F)	1.7 C (3.1 F)	14 years	14 of 100 (Routine)
17 December 2011	San Isidro, MX	daily high min (Tie)	22.8 C (73.0 F)	tie	28 years	3 of 100 (Routine)
16 December 2011	San Isidro, MX	daily high min (Tie)	20.6 C (69.1 F)	tie	34 years	3 of 100 (Routine)
15 December 2011	San Isidro, MX	daily high max	33.9 C (93.0 F)	1.1 C (2.0 F)	49 years	22 of 100 (Routine)
14 December 2011	San Isidro, MX	daily high max (Tie)	35.0 C (95.0 F)	tie	0 years	1 of 100 (Routine)
9 December 2011	San Isidro, MX	daily high min	22.8 C (73.0 F)	1.1 C (2.0 F)	5 years	9 of 100 (Routine)
8 December 2011	San Isidro, MX	daily high max	36.7 C (98.1 F)	1.7 C (3.1 F)	6 years	12 of 100 (Routine)
4 December 2011	San Isidro, MX	daily high max	36.7 C (98.1 F)	1.7 C (3.1 F)	0 years	10 of 100 (Routine)
3 December 2011	San Isidro, MX	daily high max	35.0 C (95.0 F)	1.1 C (2.0 F)	6 years	10 of 100 (Routine)
1 December 2011	San Isidro, MX	daily high max	36.7 C (98.1 F)	2.8 C (5.0 F)	52 years	29 of 100 (Routine)
30 November 2011	San Isidro, MX	daily high min	22.8 C (73.0 F)	1.1 C (2.0 F)	8 years	9 of 100 (Routine)

Climate Trend

31 complete years, 1959 to 2010

One stripe for each of 31 complete years at San Isidro, 1959 to 2010. Blue stripes are years cooler than the station's own mean of 26.0 C (78.7 F); red stripes are warmer. The coolest year was 1995, at 24.1 C (75.3 F), and the warmest was 2009, at 28.9 C (84.0 F). The strongest colour marks a difference of 3.0 C (5.4 F).

Annual mean temperature at San Isidro as warming stripes, 1959 to 2010
Year	Annual mean temperature	Difference from the station mean
1959	25.7 C	-0.22 C
1960	26.3 C	+0.32 C
1961	26.0 C	+0.02 C
1962	25.7 C	-0.30 C
1963	26.0 C	+0.04 C
1964	26.1 C	+0.09 C
1965	26.3 C	+0.33 C
1966	25.7 C	-0.29 C
1967	25.6 C	-0.40 C
1968	24.9 C	-1.08 C
1969	25.8 C	-0.16 C
1970	25.5 C	-0.47 C
1971	26.1 C	+0.17 C
1972	26.0 C	+0.04 C
1973	25.2 C	-0.72 C
1974	24.8 C	-1.15 C
1975	25.5 C	-0.43 C
1976	24.7 C	-1.26 C
1977	24.8 C	-1.15 C
1978	25.0 C	-0.97 C
1979	25.2 C	-0.74 C
1980	25.5 C	-0.49 C
1983	25.8 C	-0.18 C
1995	24.1 C	-1.88 C
1996	24.9 C	-1.08 C
2004	27.0 C	+1.06 C
2005	27.9 C	+1.93 C
2006	27.7 C	+1.74 C
2007	28.6 C	+2.68 C
2009	28.9 C	+2.91 C
2010	27.5 C	+1.50 C

The annual mean temperature here has risen by 0.4 C (0.2 to 0.6) per decade over 1959 to 2010. In Fahrenheit: 0.7 F (0.3 to 1.1) per decade. The slope is a straight line fitted to 31 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at San Isidro
Measure	Per decade (C)	Per decade (F)	Period	Complete years	Reading
Annual mean temperature	0.4 C (0.2 to 0.6) per decade	0.7 F (0.3 to 1.1) per decade	1959 to 2010	31	Rise
Mean daily maximum	0.5 C (0.2 to 0.7) per decade	0.9 F (0.4 to 1.3) per decade	1959 to 2010	31	Rise
Mean daily minimum	0.3 C (0.1 to 0.6) per decade	0.6 F (0.1 to 1.0) per decade	1959 to 2010	31	Rise

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

1958 to 2011

Yearly extremes at San Isidro: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	45.6 C (114.1 F)	2009	41.1 C (106.0 F)	47
Coldest night (TNn)	5.6 C (42.1 F)	1963	8.9 C (48.0 F)	47
Wettest day (Rx1day)	275.8 mm (10.9 in)	1995	80.8 mm (3.2 in)	47
Wettest five days (Rx5day)	561.3 mm (22.1 in)	1995	154.5 mm (6.1 in)	47
Longest dry spell (CDD)	142 days	2010	43 days	47

Hottest day (TXx)

The hottest day of the year at San Isidro, 1958 to 2011. The record is 45.6 C (114.1 F) in 2009, marked on the chart; the median year is 41.1 C (106.0 F).

Hottest day (TXx) at San Isidro by year
Year	Hottest day (TXx)
1958	41.7 C (107.1 F)
1959	40.0 C (104.0 F)
1960	43.9 C (111.0 F)
1961	41.7 C (107.1 F)
1962	40.6 C (105.1 F)
1963	42.8 C (109.0 F)
1964	43.9 C (111.0 F)
1965	41.1 C (106.0 F)
1966	40.0 C (104.0 F)
1967	42.8 C (109.0 F)
1968	41.7 C (107.1 F)
1969	43.9 C (111.0 F)
1970	42.8 C (109.0 F)
1971	43.3 C (109.9 F)
1972	42.8 C (109.0 F)
1973	41.7 C (107.1 F)
1974	41.1 C (106.0 F)
1975	40.6 C (105.1 F)
1976	40.6 C (105.1 F)
1977	37.8 C (100.0 F)
1978	41.1 C (106.0 F)
1979	38.9 C (102.0 F)
1980	41.7 C (107.1 F)
1981	40.6 C (105.1 F)
1982	38.9 C (102.0 F)
1983	38.9 C (102.0 F)
1984	41.1 C (106.0 F)
1985	38.9 C (102.0 F)
1986	37.8 C (100.0 F)
1987	36.7 C (98.1 F)
1988	38.9 C (102.0 F)
1990	35.6 C (96.1 F)
1991	33.9 C (93.0 F)
1992	38.9 C (102.0 F)
1993	35.6 C (96.1 F)
1994	38.9 C (102.0 F)
1995	37.8 C (100.0 F)
1996	37.8 C (100.0 F)
2003	41.7 C (107.1 F)
2004	41.7 C (107.1 F)
2005	43.9 C (111.0 F)
2006	41.7 C (107.1 F)
2007	40.6 C (105.1 F)
2008	41.7 C (107.1 F)
2009	45.6 C (114.1 F)
2010	41.7 C (107.1 F)
2011	41.7 C (107.1 F)

Coldest night (TNn)

The coldest night of the year at San Isidro, 1958 to 2011. The record is 5.6 C (42.1 F) in 1963, marked on the chart; the median year is 8.9 C (48.0 F).

Coldest night (TNn) at San Isidro by year
Year	Coldest night (TNn)
1958	11.7 C (53.1 F)
1959	10.0 C (50.0 F)
1960	7.8 C (46.0 F)
1961	10.0 C (50.0 F)
1962	7.8 C (46.0 F)
1963	5.6 C (42.1 F)
1964	8.9 C (48.0 F)
1965	6.7 C (44.1 F)
1966	8.9 C (48.0 F)
1967	8.9 C (48.0 F)
1968	7.2 C (45.0 F)
1969	8.9 C (48.0 F)
1970	5.6 C (42.1 F)
1971	6.7 C (44.1 F)
1972	6.1 C (43.0 F)
1973	7.2 C (45.0 F)
1974	7.2 C (45.0 F)
1975	9.4 C (48.9 F)
1976	8.9 C (48.0 F)
1977	5.6 C (42.1 F)
1978	7.2 C (45.0 F)
1979	8.9 C (48.0 F)
1980	5.6 C (42.1 F)
1981	6.7 C (44.1 F)
1982	10.0 C (50.0 F)
1983	8.9 C (48.0 F)
1984	8.3 C (46.9 F)
1985	8.9 C (48.0 F)
1986	10.0 C (50.0 F)
1987	8.9 C (48.0 F)
1988	8.9 C (48.0 F)
1990	6.7 C (44.1 F)
1991	7.8 C (46.0 F)
1992	7.8 C (46.0 F)
1993	11.7 C (53.1 F)
1994	11.7 C (53.1 F)
1995	7.8 C (46.0 F)
1996	10.0 C (50.0 F)
2003	10.6 C (51.1 F)
2004	10.6 C (51.1 F)
2005	8.9 C (48.0 F)
2006	8.9 C (48.0 F)
2007	12.8 C (55.0 F)
2008	13.9 C (57.0 F)
2009	11.7 C (53.1 F)
2010	13.9 C (57.0 F)
2011	13.9 C (57.0 F)

Wettest day (Rx1day)

The wettest day of the year at San Isidro, 1958 to 2011. The record is 275.8 mm (10.9 in) in 1995, marked on the chart; the median year is 80.8 mm (3.2 in).

Wettest day (Rx1day) at San Isidro by year
Year	Wettest day (Rx1day)
1958	87.4 mm (3.4 in)
1959	105.9 mm (4.2 in)
1960	84.8 mm (3.3 in)
1961	95.0 mm (3.7 in)
1962	68.8 mm (2.7 in)
1963	81.8 mm (3.2 in)
1964	64.8 mm (2.6 in)
1965	59.4 mm (2.3 in)
1966	79.2 mm (3.1 in)
1967	61.5 mm (2.4 in)
1968	96.3 mm (3.8 in)
1969	108.0 mm (4.3 in)
1970	69.3 mm (2.7 in)
1971	91.4 mm (3.6 in)
1972	109.0 mm (4.3 in)
1973	80.8 mm (3.2 in)
1974	111.3 mm (4.4 in)
1975	78.0 mm (3.1 in)
1976	85.9 mm (3.4 in)
1977	88.6 mm (3.5 in)
1978	69.3 mm (2.7 in)
1979	74.7 mm (2.9 in)
1980	121.9 mm (4.8 in)
1981	65.3 mm (2.6 in)
1982	80.3 mm (3.2 in)
1983	127.8 mm (5.0 in)
1984	72.6 mm (2.9 in)
1985	100.1 mm (3.9 in)
1986	55.1 mm (2.2 in)
1987	127.0 mm (5.0 in)
1988	39.9 mm (1.6 in)
1990	19.8 mm (0.8 in)
1991	59.9 mm (2.4 in)
1992	220.0 mm (8.7 in)
1993	33.3 mm (1.3 in)
1994	54.1 mm (2.1 in)
1995	275.8 mm (10.9 in)
1996	70.9 mm (2.8 in)
2003	84.8 mm (3.3 in)
2004	79.8 mm (3.1 in)
2005	129.8 mm (5.1 in)
2006	84.8 mm (3.3 in)
2007	159.8 mm (6.3 in)
2008	79.8 mm (3.1 in)
2009	79.8 mm (3.1 in)
2010	143.8 mm (5.7 in)
2011	49.8 mm (2.0 in)

Wettest five days (Rx5day)

The wettest five days of the year at San Isidro, 1958 to 2011. The record is 561.3 mm (22.1 in) in 1995, marked on the chart; the median year is 154.5 mm (6.1 in).

Wettest five days (Rx5day) at San Isidro by year
Year	Wettest five days (Rx5day)
1958	154.5 mm (6.1 in)
1959	136.1 mm (5.4 in)
1960	141.0 mm (5.6 in)
1961	155.5 mm (6.1 in)
1962	110.8 mm (4.4 in)
1963	173.9 mm (6.8 in)
1964	116.2 mm (4.6 in)
1965	150.4 mm (5.9 in)
1966	115.3 mm (4.5 in)
1967	120.6 mm (4.7 in)
1968	189.3 mm (7.5 in)
1969	179.9 mm (7.1 in)
1970	135.1 mm (5.3 in)
1971	142.8 mm (5.6 in)
1972	240.1 mm (9.5 in)
1973	145.0 mm (5.7 in)
1974	130.4 mm (5.1 in)
1975	170.3 mm (6.7 in)
1976	172.6 mm (6.8 in)
1977	142.8 mm (5.6 in)
1978	128.8 mm (5.1 in)
1979	144.0 mm (5.7 in)
1980	280.0 mm (11.0 in)
1981	113.9 mm (4.5 in)
1982	189.5 mm (7.5 in)
1983	252.0 mm (9.9 in)
1984	194.5 mm (7.7 in)
1985	157.8 mm (6.2 in)
1986	90.7 mm (3.6 in)
1987	193.8 mm (7.6 in)
1988	88.9 mm (3.5 in)
1990	28.7 mm (1.1 in)
1991	69.8 mm (2.7 in)
1992	302.1 mm (11.9 in)
1993	55.4 mm (2.2 in)
1994	133.0 mm (5.2 in)
1995	561.3 mm (22.1 in)
1996	197.2 mm (7.8 in)
2003	181.1 mm (7.1 in)
2004	184.2 mm (7.3 in)
2005	306.1 mm (12.1 in)
2006	161.7 mm (6.4 in)
2007	268.3 mm (10.6 in)
2008	125.5 mm (4.9 in)
2009	232.5 mm (9.2 in)
2010	203.8 mm (8.0 in)
2011	117.2 mm (4.6 in)

Longest dry spell (CDD)

The longest dry spell of the year at San Isidro, 1958 to 2011. The record is 142 days in 2010, marked on the chart; the median year is 43 days.

Longest dry spell (CDD) at San Isidro by year
Year	Longest dry spell (CDD)
1958	33 days
1959	21 days
1960	49 days
1961	37 days
1962	37 days
1963	40 days
1964	48 days
1965	78 days
1966	25 days
1967	41 days
1968	31 days
1969	41 days
1970	45 days
1971	88 days
1972	37 days
1973	58 days
1974	55 days
1975	75 days
1976	61 days
1977	15 days
1978	53 days
1979	29 days
1980	15 days
1981	24 days
1982	26 days
1983	43 days
1984	26 days
1985	43 days
1986	75 days
1987	22 days
1988	54 days
1990	19 days
1991	25 days
1992	70 days
1993	25 days
1994	17 days
1995	49 days
1996	42 days
2003	16 days
2004	46 days
2005	116 days
2006	77 days
2007	59 days
2008	69 days
2009	74 days
2010	142 days
2011	44 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

35 years, 1959 to 2010

A day with at least 84.7 mm (3.3 in) of rain is expected about once in 2 years. A day with at least 262.7 mm (10.3 in) of rain is expected about once in 100 years.

Rainfall return levels at San Isidro: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	84.7 mm (3.3 in)
5 years	110.5 mm (4.4 in)
10 years	134.1 mm (5.3 in)
25 years	174.0 mm (6.9 in)
50 years	213.2 mm (8.4 in)	Longer than the 35 years of record
100 years	262.7 mm (10.3 in)	Longer than the 35 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, 35 years of values from 1959 to 2010.

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: 275.8 mm (10.9 in) in 1995; 159.8 mm (6.3 in) in 2007; 143.8 mm (5.7 in) in 2010.

Download the Data

Data for San Isidro standing records by year: CSV or JSON. Field meanings are on the data page.
Data for San Isidro 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 2026-10-16 (16 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).