Record highRecord low2026 daily maximum2026 daily minimum
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
32.2 C (90.0 F)
-9.4 C (15.1 F)
n/a
n/a
Feb
35.6 C (96.1 F)
-7.2 C (19.0 F)
n/a
n/a
Mar
36.7 C (98.1 F)
-5.0 C (23.0 F)
n/a
n/a
Apr
38.9 C (102.0 F)
-1.1 C (30.0 F)
n/a
n/a
May
40.0 C (104.0 F)
0.6 C (33.1 F)
n/a
n/a
Jun
40.6 C (105.1 F)
5.6 C (42.1 F)
n/a
n/a
Jul
36.7 C (98.1 F)
6.7 C (44.1 F)
n/a
n/a
Aug
37.2 C (99.0 F)
6.7 C (44.1 F)
n/a
n/a
Sep
37.8 C (100.0 F)
1.7 C (35.1 F)
n/a
n/a
Oct
37.2 C (99.0 F)
-4.4 C (24.1 F)
n/a
n/a
Nov
37.2 C (99.0 F)
-6.1 C (21.0 F)
n/a
n/a
Dec
33.9 C (93.0 F)
-11.1 C (12.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Atotonilco still stand. 1982 holds the most, with 160.
Standing records at Atotonilco by the year they were set
Year set
Standing records
1969
4
1970
12
1971
35
1972
42
1973
30
1974
24
1975
15
1976
38
1977
37
1978
21
1979
47
1980
102
1981
127
1982
160
1983
83
1984
64
1985
96
1986
5
1991
29
1992
22
1993
35
1994
18
1995
23
1996
29
1997
69
1998
26
1999
11
2000
23
2001
23
2002
40
2003
26
2004
38
2005
45
2006
32
2007
33
Wettest Day of Each Month
May: 74.9 mm (2.9 in)
The wettest day on record for each calendar month at Atotonilco. The most was 74.9 mm (2.9 in) on 27 May 1983.
Record daily precipitation for each month at Atotonilco
Month
Record daily precipitation (mm)
Date
Jan
26.9 mm (1.1 in)
13 January 1985
Feb
20.3 mm (0.8 in)
1 February 1997
Mar
24.9 mm (1.0 in)
30 March 2004
Apr
12.7 mm (0.5 in)
29 April 1982
May
74.9 mm (2.9 in)
27 May 1983
Jun
50.8 mm (2.0 in)
26 June 1993
Jul
46.0 mm (1.8 in)
21 July 1991
Aug
64.8 mm (2.6 in)
20 August 1996
Sep
71.9 mm (2.8 in)
1 September 2004
Oct
67.8 mm (2.7 in)
1 October 1970
Nov
24.9 mm (1.0 in)
25 November 1982
Dec
24.9 mm (1.0 in)
18 December 1975
Period of Record Coverage
1969 to 2007
Complete yearUnder 90 percent of days
35 years of record at Atotonilco, 1969 to 2007. 7 years have data for under 90 percent of days and are left out of rankings: 1969, 1970, 1973, 1986, 1991, 1992, 1996.
Cooler than the station meanWarmer than the station mean
One stripe for each of 28 complete years at Atotonilco, 1971 to 2007. Blue stripes are years cooler than the station's own mean of 16.9 C (62.4 F); red stripes are warmer. The coolest year was 2004, at 14.3 C (57.7 F), and the warmest was 1981, at 21.3 C (70.4 F). The strongest colour marks a difference of 4.5 C (8.1 F).
Annual mean temperature at Atotonilco as warming stripes, 1971 to 2007
Year
Annual mean temperature
Difference from the station mean
1971
17.5 C
+0.55 C
1972
18.1 C
+1.16 C
1974
16.5 C
-0.45 C
1975
16.5 C
-0.42 C
1976
15.6 C
-1.30 C
1977
17.4 C
+0.52 C
1978
17.6 C
+0.65 C
1979
18.2 C
+1.30 C
1980
19.7 C
+2.83 C
1981
21.3 C
+4.41 C
1982
20.9 C
+3.97 C
1983
19.9 C
+3.02 C
1984
20.2 C
+3.29 C
1985
20.3 C
+3.44 C
1993
15.4 C
-1.53 C
1994
16.0 C
-0.86 C
1995
15.4 C
-1.51 C
1997
14.4 C
-2.46 C
1998
15.9 C
-1.05 C
1999
15.5 C
-1.41 C
2000
15.9 C
-0.97 C
2001
15.7 C
-1.25 C
2002
15.4 C
-1.52 C
2003
14.8 C
-2.09 C
2004
14.3 C
-2.60 C
2005
14.9 C
-1.99 C
2006
15.0 C
-1.95 C
2007
15.1 C
-1.77 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 2007
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)
40.6 C (105.1 F)
1982
33.9 C (93.0 F)
35
Coldest night (TNn)
-11.1 C (12.0 F)
2004
-5.0 C (23.0 F)
35
Wettest day (Rx1day)
74.9 mm (2.9 in)
1983
39.9 mm (1.6 in)
35
Wettest five days (Rx5day)
119.6 mm (4.7 in)
1983
76.6 mm (3.0 in)
35
Longest dry spell (CDD)
170 days
1977
94 days
35
Hottest day (TXx)
The hottest day of the year at Atotonilco, 1969 to 2007. The record is 40.6 C (105.1 F) in 1982, marked on the chart; the median year is 33.9 C (93.0 F).
Hottest day (TXx) at Atotonilco by year
Year
Hottest day (TXx)
1969
35.6 C (96.1 F)
1970
30.0 C (86.0 F)
1971
35.6 C (96.1 F)
1972
37.8 C (100.0 F)
1973
33.9 C (93.0 F)
1974
33.9 C (93.0 F)
1975
33.9 C (93.0 F)
1976
32.8 C (91.0 F)
1977
33.9 C (93.0 F)
1978
35.6 C (96.1 F)
1979
35.0 C (95.0 F)
1980
37.8 C (100.0 F)
1981
38.9 C (102.0 F)
1982
40.6 C (105.1 F)
1983
40.0 C (104.0 F)
1984
40.0 C (104.0 F)
1985
40.0 C (104.0 F)
1986
29.4 C (84.9 F)
1991
35.6 C (96.1 F)
1992
35.0 C (95.0 F)
1993
32.8 C (91.0 F)
1994
33.9 C (93.0 F)
1995
31.7 C (89.1 F)
1996
31.7 C (89.1 F)
1997
31.7 C (89.1 F)
1998
33.9 C (93.0 F)
1999
33.9 C (93.0 F)
2000
32.8 C (91.0 F)
2001
31.7 C (89.1 F)
2002
32.8 C (91.0 F)
2003
33.9 C (93.0 F)
2004
33.9 C (93.0 F)
2005
35.0 C (95.0 F)
2006
31.7 C (89.1 F)
2007
33.9 C (93.0 F)
Coldest night (TNn)
The coldest night of the year at Atotonilco, 1969 to 2007. The record is -11.1 C (12.0 F) in 2004, marked on the chart; the median year is -5.0 C (23.0 F).
Coldest night (TNn) at Atotonilco by year
Year
Coldest night (TNn)
1969
0.0 C (32.0 F)
1970
-5.0 C (23.0 F)
1971
-5.0 C (23.0 F)
1972
-2.2 C (28.0 F)
1973
-2.2 C (28.0 F)
1974
-5.0 C (23.0 F)
1975
-5.0 C (23.0 F)
1976
-6.7 C (19.9 F)
1977
-2.2 C (28.0 F)
1978
-1.7 C (28.9 F)
1979
-4.4 C (24.1 F)
1980
-6.1 C (21.0 F)
1981
-3.3 C (26.1 F)
1982
-3.3 C (26.1 F)
1983
-6.1 C (21.0 F)
1984
-4.4 C (24.1 F)
1985
-8.3 C (17.1 F)
1986
-2.2 C (28.0 F)
1991
0.6 C (33.1 F)
1992
0.0 C (32.0 F)
1993
-3.3 C (26.1 F)
1994
0.0 C (32.0 F)
1995
-3.3 C (26.1 F)
1996
-8.3 C (17.1 F)
1997
-10.0 C (14.0 F)
1998
-9.4 C (15.1 F)
1999
-8.3 C (17.1 F)
2000
-5.0 C (23.0 F)
2001
-8.3 C (17.1 F)
2002
-7.2 C (19.0 F)
2003
-8.3 C (17.1 F)
2004
-11.1 C (12.0 F)
2005
-5.0 C (23.0 F)
2006
-8.3 C (17.1 F)
2007
-5.0 C (23.0 F)
Wettest day (Rx1day)
The wettest day of the year at Atotonilco, 1969 to 2007. The record is 74.9 mm (2.9 in) in 1983, marked on the chart; the median year is 39.9 mm (1.6 in).
Wettest day (Rx1day) at Atotonilco by year
Year
Wettest day (Rx1day)
1969
67.8 mm (2.7 in)
1970
67.8 mm (2.7 in)
1971
43.9 mm (1.7 in)
1972
47.0 mm (1.9 in)
1973
35.8 mm (1.4 in)
1974
31.5 mm (1.2 in)
1975
24.9 mm (1.0 in)
1976
35.3 mm (1.4 in)
1977
5.1 mm (0.20 in)
1978
39.9 mm (1.6 in)
1979
11.2 mm (0.4 in)
1980
8.9 mm (0.35 in)
1981
30.0 mm (1.2 in)
1982
31.5 mm (1.2 in)
1983
74.9 mm (2.9 in)
1984
32.8 mm (1.3 in)
1985
41.1 mm (1.6 in)
1986
3.8 mm (0.15 in)
1991
46.0 mm (1.8 in)
1992
42.9 mm (1.7 in)
1993
56.9 mm (2.2 in)
1994
35.8 mm (1.4 in)
1995
45.0 mm (1.8 in)
1996
64.8 mm (2.6 in)
1997
27.9 mm (1.1 in)
1998
37.3 mm (1.5 in)
1999
32.3 mm (1.3 in)
2000
42.9 mm (1.7 in)
2001
24.9 mm (1.0 in)
2002
64.8 mm (2.6 in)
2003
59.9 mm (2.4 in)
2004
71.9 mm (2.8 in)
2005
52.3 mm (2.1 in)
2006
39.9 mm (1.6 in)
2007
30.0 mm (1.2 in)
Wettest five days (Rx5day)
The wettest five days of the year at Atotonilco, 1969 to 2007. The record is 119.6 mm (4.7 in) in 1983, marked on the chart; the median year is 76.6 mm (3.0 in).
Wettest five days (Rx5day) at Atotonilco by year
Year
Wettest five days (Rx5day)
1969
68.1 mm (2.7 in)
1970
82.6 mm (3.3 in)
1971
99.5 mm (3.9 in)
1972
104.1 mm (4.1 in)
1973
111.0 mm (4.4 in)
1974
54.4 mm (2.1 in)
1975
63.1 mm (2.5 in)
1976
77.8 mm (3.1 in)
1977
7.4 mm (0.29 in)
1978
89.9 mm (3.5 in)
1979
25.7 mm (1.0 in)
1980
15.3 mm (0.6 in)
1981
73.5 mm (2.9 in)
1982
44.3 mm (1.7 in)
1983
119.6 mm (4.7 in)
1984
79.5 mm (3.1 in)
1985
109.4 mm (4.3 in)
1986
3.8 mm (0.15 in)
1991
82.5 mm (3.2 in)
1992
60.7 mm (2.4 in)
1993
93.8 mm (3.7 in)
1994
55.1 mm (2.2 in)
1995
69.9 mm (2.8 in)
1996
107.5 mm (4.2 in)
1997
47.2 mm (1.9 in)
1998
76.6 mm (3.0 in)
1999
76.5 mm (3.0 in)
2000
105.2 mm (4.1 in)
2001
54.9 mm (2.2 in)
2002
104.5 mm (4.1 in)
2003
93.7 mm (3.7 in)
2004
113.3 mm (4.5 in)
2005
54.6 mm (2.1 in)
2006
97.3 mm (3.8 in)
2007
64.5 mm (2.5 in)
Longest dry spell (CDD)
The longest dry spell of the year at Atotonilco, 1969 to 2007. The record is 170 days in 1977, marked on the chart; the median year is 94 days.
Longest dry spell (CDD) at Atotonilco by year
Year
Longest dry spell (CDD)
1969
62 days
1970
91 days
1971
81 days
1972
76 days
1973
71 days
1974
149 days
1975
145 days
1976
94 days
1977
170 days
1978
136 days
1979
98 days
1980
134 days
1981
84 days
1982
111 days
1983
124 days
1984
104 days
1985
83 days
1986
32 days
1991
34 days
1992
50 days
1993
83 days
1994
56 days
1995
166 days
1996
118 days
1997
53 days
1998
156 days
1999
156 days
2000
117 days
2001
83 days
2002
49 days
2003
66 days
2004
74 days
2005
115 days
2006
134 days
2007
137 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.
Frost Dates and Growing Season
24 years with a frost
Across 24 years with a frost, the median last spring frost at Atotonilco falls on 28 February and the median first autumn frost on 18 November, which leaves a median of 258 days between them.
Frost dates and growing season at Atotonilco
Measure
Median, all years
Earliest period
Recent period (1971 to 2007)
Recent against earliest
Fitted trend
Last spring frost
28 February
n/a
28 February
n/a
n/a
First autumn frost
18 November
n/a
18 November
n/a
n/a
Growing days
258 days
n/a
258 days
n/a
n/a
A frost day is a day with a daily minimum at or below 0 C (32 F). The last spring frost and the first autumn frost are the last and first such days of the cold season, and growing days are the days between them. A negative trend for the last spring frost means it comes earlier.
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.