Santa Ana Tlacotenco Weather Records (MXN00009045)

Record envelope, standing records and threshold days for Santa Ana Tlacotenco (MXN00009045), Mexico, with 44 years of record.

Key Facts for Santa Ana Tlacotenco

Santa Ana Tlacotenco (MXN00009045) is a weather station in Mexico at 19.17 latitude and -99.00 longitude, 2,595 m (8,513 ft) above sea level.
The station reports from 1969 to 2012, 44 years of record.
1,464 records set at Santa Ana Tlacotenco still stand.
Records are tracked for prcp: an element needs 30 years of data to be eligible.
Santa Ana Tlacotenco set a monthly record daily precipitation of 25.7 mm (1.0 in) on 5 November 2012.

About the Station

Location: Mexico, 19.17 latitude, -99.00 longitude.
Elevation: 2,595 m (8,513 ft).
Period of record: 1969 to 2012, 44 years.
Eligible elements: 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 Santa Ana Tlacotenco. 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 Santa Ana Tlacotenco, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	25.6 C (78.1 F)	-2.2 C (28.0 F)	n/a	n/a
Feb	27.8 C (82.0 F)	-1.1 C (30.0 F)	n/a	n/a
Mar	30.0 C (86.0 F)	-2.2 C (28.0 F)	n/a	n/a
Apr	30.6 C (87.1 F)	3.3 C (37.9 F)	n/a	n/a
May	35.6 C (96.1 F)	5.0 C (41.0 F)	n/a	n/a
Jun	30.0 C (86.0 F)	5.6 C (42.1 F)	n/a	n/a
Jul	26.7 C (80.1 F)	6.1 C (43.0 F)	n/a	n/a
Aug	26.7 C (80.1 F)	7.2 C (45.0 F)	n/a	n/a
Sep	26.7 C (80.1 F)	5.0 C (41.0 F)	n/a	n/a
Oct	27.8 C (82.0 F)	1.7 C (35.1 F)	n/a	n/a
Nov	26.1 C (79.0 F)	-1.1 C (30.0 F)	n/a	n/a
Dec	27.8 C (82.0 F)	-0.6 C (30.9 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at Santa Ana Tlacotenco still stand. 1983 holds the most, with 84.

Standing records at Santa Ana Tlacotenco by the year they were set
Year set	Standing records
1979	6
1980	64
1981	57
1982	57
1983	84
1984	59
1985	58
1986	50
1987	74
1988	57
1989	55
1990	39
1991	56
1992	62
1993	75
1994	34
1995	83
1996	48
1997	71
1998	68
2005	74
2006	52
2007	30
2008	36
2011	63
2012	52

Wettest Day of Each Month

Jun: 89.9 mm (3.5 in)

The wettest day on record for each calendar month at Santa Ana Tlacotenco. The most was 89.9 mm (3.5 in) on 21 June 1989.

Record daily precipitation for each month at Santa Ana Tlacotenco
Month	Record daily precipitation (mm)	Date
Jan	39.9 mm (1.6 in)	25 January 1980
Feb	19.6 mm (0.8 in)	2 February 1992
Mar	36.8 mm (1.4 in)	4 March 1988
Apr	38.6 mm (1.5 in)	23 April 1973
May	35.3 mm (1.4 in)	24 May 1972
Jun	89.9 mm (3.5 in)	21 June 1989
Jul	46.2 mm (1.8 in)	2 July 1974
Aug	47.8 mm (1.9 in)	29 August 2011
Sep	77.5 mm (3.1 in)	4 September 1988
Oct	70.1 mm (2.8 in)	10 October 1976
Nov	25.7 mm (1.0 in)	5 November 2012
Dec	20.8 mm (0.8 in)	31 December 1995

Period of Record Coverage

1979 to 2012

26 years of record at Santa Ana Tlacotenco, 1979 to 2012. 5 years have data for under 90 percent of days and are left out of rankings: 1979, 1990, 1994, 1998, 2006.

Days with data per year at Santa Ana Tlacotenco
Year	Days with data	Share of year	Complete
1979	30	8%	No
1980	366	100%	Yes
1981	365	100%	Yes
1982	365	100%	Yes
1983	364	100%	Yes
1984	366	100%	Yes
1985	365	100%	Yes
1986	365	100%	Yes
1987	365	100%	Yes
1988	366	100%	Yes
1989	363	99%	Yes
1990	304	83%	No
1991	365	100%	Yes
1992	366	100%	Yes
1993	365	100%	Yes
1994	184	50%	No
1995	365	100%	Yes
1996	366	100%	Yes
1997	365	100%	Yes
1998	243	67%	No
2005	365	100%	Yes
2006	267	73%	No
2007	333	91%	Yes
2008	333	91%	Yes
2011	363	99%	Yes
2012	365	100%	Yes

Latest Records

Latest records at Santa Ana Tlacotenco
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
5 November 2012	Santa Ana Tlacotenco, MX	monthly rain	25.7 mm (1.0 in)	3.9 mm (0.15 in)	16 years	25 of 100 (Routine)
20 August 2012	Santa Ana Tlacotenco, MX	daily rain	21.1 mm (0.8 in)	9.7 mm (0.38 in)	25 years	20 of 100 (Routine)
9 February 2012	Santa Ana Tlacotenco, MX	daily rain	7.1 mm (0.28 in)	2.8 mm (0.11 in)	16 years	15 of 100 (Routine)
8 February 2012	Santa Ana Tlacotenco, MX	daily rain	1.8 mm (0.07 in)	1.0 mm (0.04 in)	41 years	18 of 100 (Routine)
7 February 2012	Santa Ana Tlacotenco, MX	daily rain	1.3 mm (0.05 in)	0.5 mm (0.02 in)	22 years	11 of 100 (Routine)
29 January 2012	Santa Ana Tlacotenco, MX	daily rain	7.9 mm (0.31 in)	2.8 mm (0.11 in)	20 years	13 of 100 (Routine)
9 October 2011	Santa Ana Tlacotenco, MX	daily rain	7.9 mm (0.31 in)	1.5 mm (0.06 in)	18 years	10 of 100 (Routine)
15 September 2011	Santa Ana Tlacotenco, MX	daily rain	19.8 mm (0.8 in)	3.5 mm (0.14 in)	29 years	16 of 100 (Routine)
29 August 2011	Santa Ana Tlacotenco, MX	monthly rain	47.8 mm (1.9 in)	3.3 mm (0.13 in)	32 years	27 of 100 (Routine)
23 July 2011	Santa Ana Tlacotenco, MX	daily rain	23.9 mm (0.9 in)	4.6 mm (0.18 in)	37 years	20 of 100 (Routine)
30 June 2011	Santa Ana Tlacotenco, MX	daily rain	53.8 mm (2.1 in)	33.0 mm (1.3 in)	2 years	40 of 100 (Notable)
19 April 2011	Santa Ana Tlacotenco, MX	daily rain	8.4 mm (0.33 in)	5.6 mm (0.22 in)	13 years	16 of 100 (Routine)
5 August 2008	Santa Ana Tlacotenco, MX	daily rain	14.0 mm (0.6 in)	2.6 mm (0.10 in)	33 years	16 of 100 (Routine)
30 June 2008	Santa Ana Tlacotenco, MX	daily rain	20.8 mm (0.8 in)	1.0 mm (0.04 in)	13 years	8 of 100 (Routine)
16 June 2008	Santa Ana Tlacotenco, MX	daily rain	45.0 mm (1.8 in)	18.6 mm (0.7 in)	23 years	30 of 100 (Routine)
8 June 2008	Santa Ana Tlacotenco, MX	daily rain	20.3 mm (0.8 in)	7.9 mm (0.31 in)	35 years	20 of 100 (Routine)
7 June 2008	Santa Ana Tlacotenco, MX	daily rain	25.4 mm (1.0 in)	2.0 mm (0.08 in)	38 years	17 of 100 (Routine)
26 April 2008	Santa Ana Tlacotenco, MX	daily rain	7.9 mm (0.31 in)	3.1 mm (0.12 in)	1 year	8 of 100 (Routine)
29 February 2008	Santa Ana Tlacotenco, MX	daily rain	1.8 mm (0.07 in)	1.8 mm (0.07 in)	36 years	17 of 100 (Routine)
5 December 2007	Santa Ana Tlacotenco, MX	daily rain (Tie)	0.8 mm (0.03 in)	tie	37 years	3 of 100 (Routine)

Climate Trend

19 complete years, 1980 to 2012

One stripe for each of 19 complete years at Santa Ana Tlacotenco, 1980 to 2012. Blue stripes are years cooler than the station's own mean of 15.2 C (59.4 F); red stripes are warmer. The coolest year was 1985, at 14.5 C (58.0 F), and the warmest was 2011, at 16.2 C (61.1 F). The strongest colour marks a difference of 1.0 C (1.8 F).

Annual mean temperature at Santa Ana Tlacotenco as warming stripes, 1980 to 2012
Year	Annual mean temperature	Difference from the station mean
1980	14.9 C	-0.28 C
1981	14.5 C	-0.67 C
1982	15.3 C	+0.12 C
1983	15.0 C	-0.18 C
1984	14.5 C	-0.68 C
1985	14.5 C	-0.76 C
1986	14.6 C	-0.60 C
1987	15.0 C	-0.26 C
1988	14.9 C	-0.35 C
1989	14.7 C	-0.53 C
1991	15.6 C	+0.38 C
1992	15.1 C	-0.14 C
1993	16.1 C	+0.86 C
1995	15.8 C	+0.54 C
1996	15.0 C	-0.24 C
1997	15.6 C	+0.36 C
2005	16.0 C	+0.83 C
2011	16.2 C	+0.96 C
2012	15.8 C	+0.63 C

This station does not have enough complete years (30 are needed) to fit a temperature trend.

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

1969 to 2012

Yearly extremes at Santa Ana Tlacotenco: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	35.6 C (96.1 F)	2011	28.9 C (84.0 F)	26
Coldest night (TNn)	-2.2 C (28.0 F)	1986	0.6 C (33.1 F)	26
Wettest day (Rx1day)	89.9 mm (3.5 in)	1989	38.9 mm (1.5 in)	36
Wettest five days (Rx5day)	163.8 mm (6.4 in)	1976	72.7 mm (2.9 in)	36
Longest dry spell (CDD)	128 days	1998	61 days	36

Hottest day (TXx)

The hottest day of the year at Santa Ana Tlacotenco, 1969 to 2012. The record is 35.6 C (96.1 F) in 2011, marked on the chart; the median year is 28.9 C (84.0 F).

Hottest day (TXx) at Santa Ana Tlacotenco by year
Year	Hottest day (TXx)
1969	n/a
1970	n/a
1971	n/a
1972	n/a
1973	n/a
1974	n/a
1975	n/a
1976	n/a
1977	n/a
1978	n/a
1979	23.3 C (73.9 F)
1980	28.9 C (84.0 F)
1981	28.3 C (82.9 F)
1982	30.0 C (86.0 F)
1983	30.0 C (86.0 F)
1984	28.9 C (84.0 F)
1985	27.8 C (82.0 F)
1986	28.3 C (82.9 F)
1987	27.8 C (82.0 F)
1988	28.9 C (84.0 F)
1989	28.9 C (84.0 F)
1990	28.9 C (84.0 F)
1991	30.0 C (86.0 F)
1992	28.9 C (84.0 F)
1993	28.9 C (84.0 F)
1994	28.9 C (84.0 F)
1995	28.9 C (84.0 F)
1996	28.9 C (84.0 F)
1997	27.8 C (82.0 F)
1998	32.8 C (91.0 F)
2005	28.9 C (84.0 F)
2006	26.7 C (80.1 F)
2007	27.8 C (82.0 F)
2008	27.8 C (82.0 F)
2011	35.6 C (96.1 F)
2012	30.0 C (86.0 F)

Coldest night (TNn)

The coldest night of the year at Santa Ana Tlacotenco, 1969 to 2012. The record is -2.2 C (28.0 F) in 1986, marked on the chart; the median year is 0.6 C (33.1 F).

Coldest night (TNn) at Santa Ana Tlacotenco by year
Year	Coldest night (TNn)
1969	n/a
1970	n/a
1971	n/a
1972	n/a
1973	n/a
1974	n/a
1975	n/a
1976	n/a
1977	n/a
1978	n/a
1979	3.9 C (39.0 F)
1980	-0.6 C (30.9 F)
1981	0.0 C (32.0 F)
1982	0.6 C (33.1 F)
1983	0.6 C (33.1 F)
1984	1.7 C (35.1 F)
1985	0.0 C (32.0 F)
1986	-2.2 C (28.0 F)
1987	-1.1 C (30.0 F)
1988	-1.1 C (30.0 F)
1989	-1.1 C (30.0 F)
1990	1.1 C (34.0 F)
1991	2.8 C (37.0 F)
1992	2.8 C (37.0 F)
1993	1.7 C (35.1 F)
1994	0.6 C (33.1 F)
1995	1.7 C (35.1 F)
1996	-1.1 C (30.0 F)
1997	0.6 C (33.1 F)
1998	1.7 C (35.1 F)
2005	2.8 C (37.0 F)
2006	0.0 C (32.0 F)
2007	2.8 C (37.0 F)
2008	0.0 C (32.0 F)
2011	0.0 C (32.0 F)
2012	2.8 C (37.0 F)

Wettest day (Rx1day)

The wettest day of the year at Santa Ana Tlacotenco, 1969 to 2012. The record is 89.9 mm (3.5 in) in 1989, marked on the chart; the median year is 38.9 mm (1.5 in).

Wettest day (Rx1day) at Santa Ana Tlacotenco by year
Year	Wettest day (Rx1day)
1969	30.0 mm (1.2 in)
1970	31.0 mm (1.2 in)
1971	35.3 mm (1.4 in)
1972	38.9 mm (1.5 in)
1973	60.2 mm (2.4 in)
1974	46.2 mm (1.8 in)
1975	35.3 mm (1.4 in)
1976	70.1 mm (2.8 in)
1977	31.0 mm (1.2 in)
1978	43.9 mm (1.7 in)
1979	53.3 mm (2.1 in)
1980	39.9 mm (1.6 in)
1981	31.0 mm (1.2 in)
1982	24.4 mm (1.0 in)
1983	56.4 mm (2.2 in)
1984	35.3 mm (1.4 in)
1985	45.2 mm (1.8 in)
1986	35.3 mm (1.4 in)
1987	41.4 mm (1.6 in)
1988	77.5 mm (3.1 in)
1989	89.9 mm (3.5 in)
1990	38.9 mm (1.5 in)
1991	35.3 mm (1.4 in)
1992	40.9 mm (1.6 in)
1993	20.8 mm (0.8 in)
1994	15.7 mm (0.6 in)
1995	40.9 mm (1.6 in)
1996	36.3 mm (1.4 in)
1997	25.9 mm (1.0 in)
1998	35.3 mm (1.4 in)
2005	30.0 mm (1.2 in)
2006	39.9 mm (1.6 in)
2007	57.2 mm (2.3 in)
2008	45.0 mm (1.8 in)
2011	53.8 mm (2.1 in)
2012	31.8 mm (1.3 in)

Wettest five days (Rx5day)

The wettest five days of the year at Santa Ana Tlacotenco, 1969 to 2012. The record is 163.8 mm (6.4 in) in 1976, marked on the chart; the median year is 72.7 mm (2.9 in).

Wettest five days (Rx5day) at Santa Ana Tlacotenco by year
Year	Wettest five days (Rx5day)
1969	72.9 mm (2.9 in)
1970	65.8 mm (2.6 in)
1971	58.3 mm (2.3 in)
1972	69.3 mm (2.7 in)
1973	71.3 mm (2.8 in)
1974	76.3 mm (3.0 in)
1975	59.2 mm (2.3 in)
1976	163.8 mm (6.4 in)
1977	59.5 mm (2.3 in)
1978	87.6 mm (3.4 in)
1979	97.5 mm (3.8 in)
1980	82.4 mm (3.2 in)
1981	59.5 mm (2.3 in)
1982	63.6 mm (2.5 in)
1983	96.8 mm (3.8 in)
1984	99.4 mm (3.9 in)
1985	84.4 mm (3.3 in)
1986	67.1 mm (2.6 in)
1987	64.5 mm (2.5 in)
1988	145.6 mm (5.7 in)
1989	105.1 mm (4.1 in)
1990	99.6 mm (3.9 in)
1991	79.2 mm (3.1 in)
1992	98.0 mm (3.9 in)
1993	58.7 mm (2.3 in)
1994	27.7 mm (1.1 in)
1995	99.6 mm (3.9 in)
1996	42.9 mm (1.7 in)
1997	54.6 mm (2.1 in)
1998	59.6 mm (2.3 in)
2005	72.4 mm (2.9 in)
2006	87.7 mm (3.5 in)
2007	102.1 mm (4.0 in)
2008	61.4 mm (2.4 in)
2011	105.4 mm (4.1 in)
2012	59.0 mm (2.3 in)

Longest dry spell (CDD)

The longest dry spell of the year at Santa Ana Tlacotenco, 1969 to 2012. The record is 128 days in 1998, marked on the chart; the median year is 61 days.

Longest dry spell (CDD) at Santa Ana Tlacotenco by year
Year	Longest dry spell (CDD)
1969	69 days
1970	63 days
1971	48 days
1972	31 days
1973	57 days
1974	40 days
1975	73 days
1976	44 days
1977	49 days
1978	47 days
1979	79 days
1980	68 days
1981	26 days
1982	78 days
1983	72 days
1984	36 days
1985	55 days
1986	111 days
1987	49 days
1988	61 days
1989	66 days
1990	65 days
1991	87 days
1992	45 days
1993	59 days
1994	45 days
1995	51 days
1996	115 days
1997	74 days
1998	128 days
2005	65 days
2006	38 days
2007	61 days
2008	61 days
2011	105 days
2012	56 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

33 years, 1969 to 2012

A day with at least 38.9 mm (1.5 in) of rain is expected about once in 2 years. A day with at least 102.1 mm (4.0 in) of rain is expected about once in 100 years.

Rainfall return levels at Santa Ana Tlacotenco: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	38.9 mm (1.5 in)
5 years	51.9 mm (2.0 in)
10 years	61.9 mm (2.4 in)
25 years	76.3 mm (3.0 in)
50 years	88.5 mm (3.5 in)	Longer than the 33 years of record
100 years	102.1 mm (4.0 in)	Longer than the 33 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, 33 years of values from 1969 to 2012.

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: 89.9 mm (3.5 in) in 1989; 77.5 mm (3.1 in) in 1988; 70.1 mm (2.8 in) in 1976.

Download the Data

Data for Santa Ana Tlacotenco standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Santa Ana Tlacotenco 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).