Atotonilco Weather Records (MXN00013096)

Record envelope, standing records and threshold days for Atotonilco (MXN00013096), Mexico, with 39 years of record.

Key Facts for Atotonilco

Atotonilco (MXN00013096) is a weather station in Mexico at 20.27 latitude and -98.65 longitude, 2,112 m (6,929 ft) above sea level.
The station reports from 1974 to 2012, 39 years of record.
1,464 records set at Atotonilco still stand.
Records are tracked for tmax, tmin, prcp: an element needs 30 years of data to be eligible.
Atotonilco set a daily record low minimum temperature of 7.2 C (45.0 F) on 23 September 2012.

About the Station

Location: Mexico, 20.27 latitude, -98.65 longitude.
Elevation: 2,112 m (6,929 ft).
Period of record: 1974 to 2012, 39 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 Atotonilco. 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 Atotonilco, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	28.9 C (84.0 F)	-4.4 C (24.1 F)	n/a	n/a
Feb	31.7 C (89.1 F)	-2.2 C (28.0 F)	n/a	n/a
Mar	33.9 C (93.0 F)	-3.3 C (26.1 F)	n/a	n/a
Apr	36.7 C (98.1 F)	1.7 C (35.1 F)	n/a	n/a
May	35.6 C (96.1 F)	5.0 C (41.0 F)	n/a	n/a
Jun	33.9 C (93.0 F)	2.8 C (37.0 F)	n/a	n/a
Jul	28.9 C (84.0 F)	1.7 C (35.1 F)	n/a	n/a
Aug	27.8 C (82.0 F)	3.9 C (39.0 F)	n/a	n/a
Sep	27.8 C (82.0 F)	1.7 C (35.1 F)	n/a	n/a
Oct	30.0 C (86.0 F)	0.6 C (33.1 F)	n/a	n/a
Nov	30.0 C (86.0 F)	-1.1 C (30.0 F)	n/a	n/a
Dec	30.0 C (86.0 F)	-4.4 C (24.1 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at Atotonilco still stand. 1974 holds the most, with 143.

Standing records at Atotonilco by the year they were set
Year set	Standing records
1974	143
1975	46
1976	60
1977	31
1978	31
1979	63
1980	36
1981	25
1982	30
1983	49
1984	52
1985	33
1986	36
1987	73
1988	37
1989	28
1990	21
1991	38
1992	28
1993	32
1994	31
1995	41
1996	25
1997	50
1998	76
1999	26
2000	16
2001	18
2002	23
2003	37
2004	44
2005	28
2006	23
2007	7
2008	14
2009	26
2010	29
2011	29
2012	29

All-Time Record Progression

2 new records

2 all-time records were set at Atotonilco between 15 April 2005 and 22 August 2007. Each dot is a new record.

When Atotonilco set new all-time records
Date	Kind	Detail
2005-04-15	Record high maximum temperature	Record high maximum temperature 36.7 C (98.1 F)
2007-08-22	Record daily precipitation	Record daily precipitation 118.1 mm (4.6 in)

Wettest Day of Each Month

Aug: 118.1 mm (4.6 in)

The wettest day on record for each calendar month at Atotonilco. The most was 118.1 mm (4.6 in) on 22 August 2007.

Record daily precipitation for each month at Atotonilco
Month	Record daily precipitation (mm)	Date
Jan	24.4 mm (1.0 in)	18 January 1983
Feb	28.7 mm (1.1 in)	3 February 2010
Mar	31.8 mm (1.3 in)	16 March 1978
Apr	55.4 mm (2.2 in)	7 April 1997
May	64.8 mm (2.6 in)	29 May 1992
Jun	100.1 mm (3.9 in)	30 June 2011
Jul	69.9 mm (2.8 in)	23 July 2010
Aug	118.1 mm (4.6 in)	22 August 2007
Sep	108.2 mm (4.3 in)	2 September 1988
Oct	108.5 mm (4.3 in)	5 October 1999
Nov	58.9 mm (2.3 in)	5 November 2002
Dec	15.7 mm (0.6 in)	3 December 1979

Period of Record Coverage

1974 to 2012

39 years of record at Atotonilco, 1974 to 2012. 2 years have data for under 90 percent of days and are left out of rankings: 1974, 2012.

Days with data per year at Atotonilco
Year	Days with data	Share of year	Complete
1974	269	74%	No
1975	365	100%	Yes
1976	363	99%	Yes
1977	364	100%	Yes
1978	359	98%	Yes
1979	362	99%	Yes
1980	363	99%	Yes
1981	364	100%	Yes
1982	364	100%	Yes
1983	365	100%	Yes
1984	366	100%	Yes
1985	363	99%	Yes
1986	365	100%	Yes
1987	363	99%	Yes
1988	365	100%	Yes
1989	365	100%	Yes
1990	364	100%	Yes
1991	361	99%	Yes
1992	362	99%	Yes
1993	361	99%	Yes
1994	364	100%	Yes
1995	363	99%	Yes
1996	362	99%	Yes
1997	364	100%	Yes
1998	362	99%	Yes
1999	362	99%	Yes
2000	364	99%	Yes
2001	362	99%	Yes
2002	364	100%	Yes
2003	365	100%	Yes
2004	360	98%	Yes
2005	355	97%	Yes
2006	365	100%	Yes
2007	364	100%	Yes
2008	364	99%	Yes
2009	365	100%	Yes
2010	365	100%	Yes
2011	333	91%	Yes
2012	270	74%	No

Latest Records

Latest records at Atotonilco
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
23 September 2012	Atotonilco, MX	daily low min	7.2 C (45.0 F)	0.6 C (1.1 F)	7 years	7 of 100 (Routine)
22 September 2012	Atotonilco, MX	daily low min	5.6 C (42.1 F)	1.1 C (2.0 F)	18 years	13 of 100 (Routine)
21 September 2012	Atotonilco, MX	daily low min	5.6 C (42.1 F)	2.2 C (4.0 F)	13 years	16 of 100 (Routine)
20 September 2012	Atotonilco, MX	daily low min	6.1 C (43.0 F)	1.7 C (3.1 F)	28 years	19 of 100 (Routine)
7 September 2012	Atotonilco, MX	daily high max	27.2 C (81.0 F)	2.2 C (4.0 F)	32 years	19 of 100 (Routine)
6 September 2012	Atotonilco, MX	daily high max	26.7 C (80.1 F)	1.7 C (3.1 F)	29 years	17 of 100 (Routine)
5 September 2012	Atotonilco, MX	daily high max	27.2 C (81.0 F)	1.6 C (2.9 F)	8 years	10 of 100 (Routine)
4 September 2012	Atotonilco, MX	daily high max	26.7 C (80.1 F)	1.7 C (3.1 F)	29 years	17 of 100 (Routine)
30 August 2012	Atotonilco, MX	daily high max	25.6 C (78.1 F)	0.6 C (1.1 F)	29 years	13 of 100 (Routine)
29 August 2012	Atotonilco, MX	daily high max	25.6 C (78.1 F)	0.6 C (1.1 F)	34 years	15 of 100 (Routine)
23 August 2012	Atotonilco, MX	daily rain	25.4 mm (1.0 in)	3.8 mm (0.15 in)	7 years	8 of 100 (Routine)
11 August 2012	Atotonilco, MX	daily low min (Tie)	10.0 C (50.0 F)	tie	38 years	3 of 100 (Routine)
10 August 2012	Atotonilco, MX	daily low max	15.0 C (59.0 F)	1.7 C (3.1 F)	20 years	17 of 100 (Routine)
9 August 2012	Atotonilco, MX	daily rain	87.4 mm (3.4 in)	67.8 mm (2.7 in)	37 years	54 of 100 (Notable)
9 August 2012	Atotonilco, MX	daily low max	15.0 C (59.0 F)	2.8 C (5.0 F)	20 years	22 of 100 (Routine)
4 August 2012	Atotonilco, MX	monthly high max (Tie)	27.8 C (82.0 F)	tie	0 years	3 of 100 (Routine)
3 August 2012	Atotonilco, MX	daily high max (Tie)	26.7 C (80.1 F)	tie	9 years	1 of 100 (Routine)
2 August 2012	Atotonilco, MX	monthly high max	27.8 C (82.0 F)	0.6 C (1.1 F)	28 years	23 of 100 (Routine)
1 August 2012	Atotonilco, MX	daily high max	26.7 C (80.1 F)	1.1 C (2.0 F)	26 years	15 of 100 (Routine)
31 July 2012	Atotonilco, MX	daily high max (Tie)	25.0 C (77.0 F)	tie	18 years	2 of 100 (Routine)

Climate Trend

35 complete years, 1975 to 2010

One stripe for each of 35 complete years at Atotonilco, 1975 to 2010. Blue stripes are years cooler than the station's own mean of 16.2 C (61.2 F); red stripes are warmer. The coolest year was 1976, at 15.3 C (59.5 F), and the warmest was 1998, at 17.5 C (63.5 F). The strongest colour marks a difference of 1.3 C (2.3 F).

Annual mean temperature at Atotonilco as warming stripes, 1975 to 2010
Year	Annual mean temperature	Difference from the station mean
1975	16.3 C	+0.09 C
1976	15.3 C	-0.95 C
1977	15.8 C	-0.43 C
1978	15.8 C	-0.44 C
1979	15.6 C	-0.59 C
1980	15.9 C	-0.30 C
1981	15.4 C	-0.84 C
1982	16.4 C	+0.19 C
1983	16.3 C	+0.08 C
1984	15.6 C	-0.65 C
1986	16.0 C	-0.22 C
1987	15.9 C	-0.27 C
1988	15.9 C	-0.28 C
1989	15.7 C	-0.48 C
1990	15.9 C	-0.33 C
1991	16.5 C	+0.26 C
1992	15.6 C	-0.60 C
1993	16.2 C	+0.00 C
1994	16.6 C	+0.37 C
1995	16.9 C	+0.71 C
1996	16.2 C	+0.03 C
1997	16.4 C	+0.17 C
1998	17.5 C	+1.27 C
1999	16.1 C	-0.14 C
2000	16.3 C	+0.05 C
2001	16.0 C	-0.21 C
2002	16.4 C	+0.17 C
2003	17.0 C	+0.81 C
2004	17.0 C	+0.74 C
2005	17.0 C	+0.81 C
2006	16.6 C	+0.35 C
2007	16.3 C	+0.10 C
2008	16.2 C	-0.04 C
2009	16.9 C	+0.69 C
2010	16.1 C	-0.16 C

The annual mean temperature here has risen by 0.3 C (0.1 to 0.4) per decade over 1975 to 2010. In Fahrenheit: 0.5 F (0.3 to 0.8) per decade. The slope is a straight line fitted to 35 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at Atotonilco
Measure	Per decade (C)	Per decade (F)	Period	Complete years	Reading
Annual mean temperature	0.3 C (0.1 to 0.4) per decade	0.5 F (0.3 to 0.8) per decade	1975 to 2010	35	Rise
Mean daily maximum	0.17 C (-0.04 to 0.38) per decade	0.3 F (-0.1 to 0.7) per decade	1975 to 2010	35	Not clearly different from zero
Mean daily minimum	0.4 C (0.2 to 0.6) per decade	0.7 F (0.4 to 1.0) per decade	1975 to 2010	35	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

1974 to 2012

Yearly extremes at Atotonilco: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	36.7 C (98.1 F)	2005	32.8 C (91.0 F)	39
Coldest night (TNn)	-4.4 C (24.1 F)	1983	0.0 C (32.0 F)	39
Wettest day (Rx1day)	118.1 mm (4.6 in)	2007	55.1 mm (2.2 in)	39
Wettest five days (Rx5day)	257.8 mm (10.1 in)	2011	108.5 mm (4.3 in)	39
Longest dry spell (CDD)	143 days	1998	42 days	39

Hottest day (TXx)

The hottest day of the year at Atotonilco, 1974 to 2012. The record is 36.7 C (98.1 F) in 2005, marked on the chart; the median year is 32.8 C (91.0 F).

Hottest day (TXx) at Atotonilco by year
Year	Hottest day (TXx)
1974	31.7 C (89.1 F)
1975	32.8 C (91.0 F)
1976	31.7 C (89.1 F)
1977	32.8 C (91.0 F)
1978	32.8 C (91.0 F)
1979	35.0 C (95.0 F)
1980	32.8 C (91.0 F)
1981	32.8 C (91.0 F)
1982	33.3 C (91.9 F)
1983	35.6 C (96.1 F)
1984	33.9 C (93.0 F)
1985	31.7 C (89.1 F)
1986	32.8 C (91.0 F)
1987	31.7 C (89.1 F)
1988	32.8 C (91.0 F)
1989	33.9 C (93.0 F)
1990	32.8 C (91.0 F)
1991	33.9 C (93.0 F)
1992	30.0 C (86.0 F)
1993	31.7 C (89.1 F)
1994	33.9 C (93.0 F)
1995	32.8 C (91.0 F)
1996	32.8 C (91.0 F)
1997	32.8 C (91.0 F)
1998	35.6 C (96.1 F)
1999	32.8 C (91.0 F)
2000	31.7 C (89.1 F)
2001	30.6 C (87.1 F)
2002	32.8 C (91.0 F)
2003	33.9 C (93.0 F)
2004	31.7 C (89.1 F)
2005	36.7 C (98.1 F)
2006	31.7 C (89.1 F)
2007	31.7 C (89.1 F)
2008	31.7 C (89.1 F)
2009	32.8 C (91.0 F)
2010	33.9 C (93.0 F)
2011	35.0 C (95.0 F)
2012	32.8 C (91.0 F)

Coldest night (TNn)

The coldest night of the year at Atotonilco, 1974 to 2012. The record is -4.4 C (24.1 F) in 1983, marked on the chart; the median year is 0.0 C (32.0 F).

Coldest night (TNn) at Atotonilco by year
Year	Coldest night (TNn)
1974	0.6 C (33.1 F)
1975	0.0 C (32.0 F)
1976	-2.2 C (28.0 F)
1977	-1.1 C (30.0 F)
1978	0.0 C (32.0 F)
1979	-3.3 C (26.1 F)
1980	-1.1 C (30.0 F)
1981	0.0 C (32.0 F)
1982	-1.7 C (28.9 F)
1983	-4.4 C (24.1 F)
1984	-0.6 C (30.9 F)
1985	-2.2 C (28.0 F)
1986	-4.4 C (24.1 F)
1987	-2.2 C (28.0 F)
1988	-3.3 C (26.1 F)
1989	-3.3 C (26.1 F)
1990	0.0 C (32.0 F)
1991	1.7 C (35.1 F)
1992	0.6 C (33.1 F)
1993	1.7 C (35.1 F)
1994	0.0 C (32.0 F)
1995	1.7 C (35.1 F)
1996	-1.1 C (30.0 F)
1997	-4.4 C (24.1 F)
1998	0.0 C (32.0 F)
1999	0.0 C (32.0 F)
2000	0.6 C (33.1 F)
2001	0.6 C (33.1 F)
2002	0.0 C (32.0 F)
2003	-1.1 C (30.0 F)
2004	0.0 C (32.0 F)
2005	1.7 C (35.1 F)
2006	0.6 C (33.1 F)
2007	1.7 C (35.1 F)
2008	0.6 C (33.1 F)
2009	1.7 C (35.1 F)
2010	-1.1 C (30.0 F)
2011	0.0 C (32.0 F)
2012	1.7 C (35.1 F)

Wettest day (Rx1day)

The wettest day of the year at Atotonilco, 1974 to 2012. The record is 118.1 mm (4.6 in) in 2007, marked on the chart; the median year is 55.1 mm (2.2 in).

Wettest day (Rx1day) at Atotonilco by year
Year	Wettest day (Rx1day)
1974	73.9 mm (2.9 in)
1975	40.4 mm (1.6 in)
1976	43.4 mm (1.7 in)
1977	45.0 mm (1.8 in)
1978	34.8 mm (1.4 in)
1979	40.6 mm (1.6 in)
1980	31.5 mm (1.2 in)
1981	43.4 mm (1.7 in)
1982	30.0 mm (1.2 in)
1983	38.4 mm (1.5 in)
1984	52.6 mm (2.1 in)
1985	61.5 mm (2.4 in)
1986	44.2 mm (1.7 in)
1987	29.5 mm (1.2 in)
1988	108.2 mm (4.3 in)
1989	43.4 mm (1.7 in)
1990	106.7 mm (4.2 in)
1991	33.5 mm (1.3 in)
1992	64.8 mm (2.6 in)
1993	55.1 mm (2.2 in)
1994	71.9 mm (2.8 in)
1995	71.9 mm (2.8 in)
1996	38.1 mm (1.5 in)
1997	55.4 mm (2.2 in)
1998	67.1 mm (2.6 in)
1999	108.5 mm (4.3 in)
2000	37.6 mm (1.5 in)
2001	50.3 mm (2.0 in)
2002	80.8 mm (3.2 in)
2003	48.0 mm (1.9 in)
2004	58.2 mm (2.3 in)
2005	72.9 mm (2.9 in)
2006	35.1 mm (1.4 in)
2007	118.1 mm (4.6 in)
2008	103.6 mm (4.1 in)
2009	55.6 mm (2.2 in)
2010	69.9 mm (2.8 in)
2011	100.1 mm (3.9 in)
2012	87.4 mm (3.4 in)

Wettest five days (Rx5day)

The wettest five days of the year at Atotonilco, 1974 to 2012. The record is 257.8 mm (10.1 in) in 2011, marked on the chart; the median year is 108.5 mm (4.3 in).

Wettest five days (Rx5day) at Atotonilco by year
Year	Wettest five days (Rx5day)
1974	183.8 mm (7.2 in)
1975	91.5 mm (3.6 in)
1976	78.2 mm (3.1 in)
1977	74.0 mm (2.9 in)
1978	104.4 mm (4.1 in)
1979	109.4 mm (4.3 in)
1980	82.3 mm (3.2 in)
1981	119.6 mm (4.7 in)
1982	57.7 mm (2.3 in)
1983	98.4 mm (3.9 in)
1984	129.9 mm (5.1 in)
1985	94.8 mm (3.7 in)
1986	79.0 mm (3.1 in)
1987	84.5 mm (3.3 in)
1988	215.2 mm (8.5 in)
1989	74.5 mm (2.9 in)
1990	131.3 mm (5.2 in)
1991	84.7 mm (3.3 in)
1992	94.4 mm (3.7 in)
1993	119.4 mm (4.7 in)
1994	87.5 mm (3.4 in)
1995	137.2 mm (5.4 in)
1996	93.0 mm (3.7 in)
1997	109.5 mm (4.3 in)
1998	179.7 mm (7.1 in)
1999	195.4 mm (7.7 in)
2000	86.1 mm (3.4 in)
2001	67.9 mm (2.7 in)
2002	159.9 mm (6.3 in)
2003	86.9 mm (3.4 in)
2004	170.8 mm (6.7 in)
2005	173.8 mm (6.8 in)
2006	73.4 mm (2.9 in)
2007	153.5 mm (6.0 in)
2008	148.6 mm (5.9 in)
2009	118.9 mm (4.7 in)
2010	194.8 mm (7.7 in)
2011	257.8 mm (10.1 in)
2012	108.5 mm (4.3 in)

Longest dry spell (CDD)

The longest dry spell of the year at Atotonilco, 1974 to 2012. The record is 143 days in 1998, marked on the chart; the median year is 42 days.

Longest dry spell (CDD) at Atotonilco by year
Year	Longest dry spell (CDD)
1974	22 days
1975	60 days
1976	37 days
1977	101 days
1978	29 days
1979	36 days
1980	30 days
1981	34 days
1982	46 days
1983	60 days
1984	26 days
1985	41 days
1986	78 days
1987	42 days
1988	33 days
1989	39 days
1990	32 days
1991	56 days
1992	46 days
1993	44 days
1994	29 days
1995	33 days
1996	66 days
1997	69 days
1998	143 days
1999	41 days
2000	51 days
2001	38 days
2002	36 days
2003	55 days
2004	44 days
2005	45 days
2006	58 days
2007	29 days
2008	60 days
2009	36 days
2010	50 days
2011	46 days
2012	25 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, 1975 to 2011

A day with at least 53.0 mm (2.1 in) of rain is expected about once in 2 years. A day with at least 158.0 mm (6.2 in) of rain is expected about once in 100 years.

Rainfall return levels at Atotonilco: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	53.0 mm (2.1 in)
5 years	75.5 mm (3.0 in)
10 years	92.5 mm (3.6 in)
25 years	116.4 mm (4.6 in)
50 years	136.3 mm (5.4 in)	Longer than the 37 years of record
100 years	158.0 mm (6.2 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 1975 to 2011.

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: 118.1 mm (4.6 in) in 2007; 108.5 mm (4.3 in) in 1999; 108.2 mm (4.3 in) in 1988.

Download the Data

Data for Atotonilco standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Atotonilco 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). Records are computed by this site and are not official.

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