Record highRecord low2026 daily maximum2026 daily minimum
The band shows the record high and record low for each calendar day at Alchichica. 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 Alchichica, with 2026 drawn through them
Month
Highest record high
Lowest record low
2026 highest maximum
2026 lowest minimum
Jan
26.1 C (79.0 F)
-14.4 C (6.1 F)
n/a
n/a
Feb
32.2 C (90.0 F)
-12.8 C (9.0 F)
n/a
n/a
Mar
31.1 C (88.0 F)
-10.6 C (12.9 F)
n/a
n/a
Apr
31.7 C (89.1 F)
-3.3 C (26.1 F)
n/a
n/a
May
33.9 C (93.0 F)
-5.0 C (23.0 F)
n/a
n/a
Jun
30.6 C (87.1 F)
-1.1 C (30.0 F)
n/a
n/a
Jul
27.8 C (82.0 F)
1.1 C (34.0 F)
n/a
n/a
Aug
27.8 C (82.0 F)
1.1 C (34.0 F)
n/a
n/a
Sep
27.8 C (82.0 F)
-5.0 C (23.0 F)
n/a
n/a
Oct
33.9 C (93.0 F)
-6.7 C (19.9 F)
n/a
n/a
Nov
27.8 C (82.0 F)
-15.0 C (5.0 F)
n/a
n/a
Dec
30.0 C (86.0 F)
-10.0 C (14.0 F)
n/a
n/a
Which Years Hold Standing Records
1,464 standing records
Year with most
1,464 records at Alchichica still stand. 1998 holds the most, with 81.
Standing records at Alchichica by the year they were set
Year set
Standing records
1965
29
1966
49
1967
45
1968
36
1969
41
1970
51
1971
42
1972
34
1973
36
1974
50
1975
31
1976
30
1977
28
1978
23
1979
41
1980
27
1981
34
1982
31
1983
33
1984
29
1985
9
1986
35
1987
61
1988
35
1989
32
1990
28
1991
45
1992
33
1993
18
1994
23
1995
37
1996
31
1997
44
1998
81
1999
30
2000
31
2001
24
2004
33
2005
30
2006
31
2007
21
2008
9
2009
23
Wettest Day of Each Month
Aug: 129.8 mm (5.1 in)
The wettest day on record for each calendar month at Alchichica. The most was 129.8 mm (5.1 in) on 31 August 1969.
Record daily precipitation for each month at Alchichica
Month
Record daily precipitation (mm)
Date
Jan
23.9 mm (0.9 in)
11 January 1984
Feb
17.8 mm (0.7 in)
7 February 1977
Mar
46.0 mm (1.8 in)
1 March 1999
Apr
34.5 mm (1.4 in)
24 April 2008
May
38.4 mm (1.5 in)
30 May 1974
Jun
75.2 mm (3.0 in)
21 June 1993
Jul
47.5 mm (1.9 in)
9 July 1984
Aug
129.8 mm (5.1 in)
31 August 1969
Sep
64.0 mm (2.5 in)
11 September 2009
Oct
50.8 mm (2.0 in)
20 October 1995
Nov
18.8 mm (0.7 in)
2 November 1977
Dec
27.9 mm (1.1 in)
30 December 1995
Period of Record Coverage
1965 to 2009
Complete yearUnder 90 percent of days
43 years of record at Alchichica, 1965 to 2009. 2 years have data for under 90 percent of days and are left out of rankings: 1965, 1983.
Cooler than the station meanWarmer than the station mean
One stripe for each of 39 complete years at Alchichica, 1966 to 2009. Blue stripes are years cooler than the station's own mean of 13.3 C (55.9 F); red stripes are warmer. The coolest year was 1974, at 12.1 C (53.8 F), and the warmest was 1995, at 14.4 C (57.8 F). The strongest colour marks a difference of 1.2 C (2.2 F).
Annual mean temperature at Alchichica as warming stripes, 1966 to 2009
Year
Annual mean temperature
Difference from the station mean
1966
12.6 C
-0.71 C
1967
12.3 C
-0.94 C
1969
13.1 C
-0.14 C
1970
12.4 C
-0.84 C
1971
12.5 C
-0.76 C
1972
12.9 C
-0.41 C
1973
13.1 C
-0.21 C
1974
12.1 C
-1.17 C
1975
12.5 C
-0.79 C
1976
12.2 C
-1.04 C
1977
12.7 C
-0.60 C
1978
13.1 C
-0.22 C
1979
12.9 C
-0.38 C
1980
13.1 C
-0.20 C
1981
12.9 C
-0.40 C
1982
13.2 C
-0.09 C
1984
13.2 C
-0.07 C
1985
13.2 C
-0.05 C
1986
13.2 C
-0.03 C
1987
13.9 C
+0.60 C
1988
13.7 C
+0.40 C
1989
13.1 C
-0.14 C
1990
13.6 C
+0.36 C
1991
14.0 C
+0.68 C
1992
13.9 C
+0.62 C
1993
13.8 C
+0.57 C
1994
14.2 C
+0.90 C
1995
14.4 C
+1.09 C
1996
13.8 C
+0.54 C
1997
14.3 C
+1.01 C
1999
13.3 C
-0.01 C
2000
13.3 C
+0.07 C
2001
13.6 C
+0.36 C
2004
13.8 C
+0.56 C
2005
14.1 C
+0.87 C
2006
13.4 C
+0.16 C
2007
13.6 C
+0.29 C
2008
13.4 C
+0.09 C
2009
13.5 C
+0.20 C
The annual mean temperature here has risen by 0.3 C (0.2 to 0.4) per decade over 1966 to 2009. In Fahrenheit: 0.6 F (0.4 to 0.8) per decade. The slope is a straight line fitted to 39 complete years; the brackets give its 95 percent interval.
Fitted temperature trends per decade at Alchichica
Measure
Per decade (C)
Per decade (F)
Period
Complete years
Reading
Annual mean temperature
0.3 C (0.2 to 0.4) per decade
0.6 F (0.4 to 0.8) per decade
1966 to 2009
39
Rise
Mean daily maximum
0.6 C (0.5 to 0.7) per decade
1.0 F (0.8 to 1.3) per decade
1966 to 2009
39
Rise
Mean daily minimum
0.11 C (-0.04 to 0.25) per decade
0.2 F (-0.1 to 0.5) per decade
1966 to 2009
39
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
1965 to 2009
Yearly extremes at Alchichica: the record and the median year
Measure
Record
Year of the record
Median year
Years with a value
Hottest day (TXx)
33.9 C (93.0 F)
1983
30.0 C (86.0 F)
43
Coldest night (TNn)
-15.0 C (5.0 F)
1970
-7.2 C (19.0 F)
43
Wettest day (Rx1day)
129.8 mm (5.1 in)
1969
37.1 mm (1.5 in)
43
Wettest five days (Rx5day)
181.4 mm (7.1 in)
1969
63.9 mm (2.5 in)
43
Longest dry spell (CDD)
102 days
1973
58 days
43
Hottest day (TXx)
The hottest day of the year at Alchichica, 1965 to 2009. The record is 33.9 C (93.0 F) in 1983, marked on the chart; the median year is 30.0 C (86.0 F).
Hottest day (TXx) at Alchichica by year
Year
Hottest day (TXx)
1965
26.7 C (80.1 F)
1966
27.8 C (82.0 F)
1967
28.9 C (84.0 F)
1968
30.6 C (87.1 F)
1969
28.9 C (84.0 F)
1970
30.0 C (86.0 F)
1971
30.6 C (87.1 F)
1972
27.8 C (82.0 F)
1973
29.4 C (84.9 F)
1974
27.2 C (81.0 F)
1975
28.9 C (84.0 F)
1976
26.1 C (79.0 F)
1977
28.9 C (84.0 F)
1978
30.0 C (86.0 F)
1979
29.4 C (84.9 F)
1980
30.0 C (86.0 F)
1981
27.8 C (82.0 F)
1982
30.0 C (86.0 F)
1983
33.9 C (93.0 F)
1984
28.9 C (84.0 F)
1985
28.9 C (84.0 F)
1986
30.0 C (86.0 F)
1987
27.8 C (82.0 F)
1988
30.0 C (86.0 F)
1989
30.0 C (86.0 F)
1990
30.0 C (86.0 F)
1991
31.1 C (88.0 F)
1992
27.8 C (82.0 F)
1993
28.9 C (84.0 F)
1994
30.0 C (86.0 F)
1995
30.6 C (87.1 F)
1996
30.0 C (86.0 F)
1997
28.9 C (84.0 F)
1998
33.9 C (93.0 F)
1999
31.7 C (89.1 F)
2000
28.9 C (84.0 F)
2001
30.0 C (86.0 F)
2004
27.8 C (82.0 F)
2005
30.0 C (86.0 F)
2006
30.6 C (87.1 F)
2007
32.2 C (90.0 F)
2008
30.0 C (86.0 F)
2009
30.0 C (86.0 F)
Coldest night (TNn)
The coldest night of the year at Alchichica, 1965 to 2009. The record is -15.0 C (5.0 F) in 1970, marked on the chart; the median year is -7.2 C (19.0 F).
Coldest night (TNn) at Alchichica by year
Year
Coldest night (TNn)
1965
-7.2 C (19.0 F)
1966
-10.0 C (14.0 F)
1967
-8.3 C (17.1 F)
1968
-7.2 C (19.0 F)
1969
-6.1 C (21.0 F)
1970
-15.0 C (5.0 F)
1971
-8.3 C (17.1 F)
1972
-9.4 C (15.1 F)
1973
-14.4 C (6.1 F)
1974
-10.6 C (12.9 F)
1975
-11.7 C (10.9 F)
1976
-12.8 C (9.0 F)
1977
-5.6 C (21.9 F)
1978
-6.1 C (21.0 F)
1979
-5.6 C (21.9 F)
1980
-9.4 C (15.1 F)
1981
-7.2 C (19.0 F)
1982
-10.0 C (14.0 F)
1983
-4.4 C (24.1 F)
1984
-7.2 C (19.0 F)
1985
-5.0 C (23.0 F)
1986
-9.4 C (15.1 F)
1987
-8.9 C (16.0 F)
1988
-5.0 C (23.0 F)
1989
-8.9 C (16.0 F)
1990
-9.4 C (15.1 F)
1991
-6.7 C (19.9 F)
1992
-5.0 C (23.0 F)
1993
-4.4 C (24.1 F)
1994
-8.3 C (17.1 F)
1995
-6.1 C (21.0 F)
1996
-7.2 C (19.0 F)
1997
-10.0 C (14.0 F)
1998
-7.2 C (19.0 F)
1999
-10.0 C (14.0 F)
2000
-6.1 C (21.0 F)
2001
-6.1 C (21.0 F)
2004
-6.7 C (19.9 F)
2005
-7.8 C (18.0 F)
2006
-8.9 C (16.0 F)
2007
-5.0 C (23.0 F)
2008
-5.0 C (23.0 F)
2009
-5.6 C (21.9 F)
Wettest day (Rx1day)
The wettest day of the year at Alchichica, 1965 to 2009. The record is 129.8 mm (5.1 in) in 1969, marked on the chart; the median year is 37.1 mm (1.5 in).
Wettest day (Rx1day) at Alchichica by year
Year
Wettest day (Rx1day)
1965
28.4 mm (1.1 in)
1966
51.1 mm (2.0 in)
1967
32.5 mm (1.3 in)
1968
33.0 mm (1.3 in)
1969
129.8 mm (5.1 in)
1970
44.2 mm (1.7 in)
1971
27.7 mm (1.1 in)
1972
52.1 mm (2.1 in)
1973
30.5 mm (1.2 in)
1974
57.7 mm (2.3 in)
1975
39.4 mm (1.6 in)
1976
27.9 mm (1.1 in)
1977
22.1 mm (0.9 in)
1978
64.3 mm (2.5 in)
1979
37.1 mm (1.5 in)
1980
31.8 mm (1.3 in)
1981
48.8 mm (1.9 in)
1982
44.7 mm (1.8 in)
1983
17.0 mm (0.7 in)
1984
47.5 mm (1.9 in)
1985
34.8 mm (1.4 in)
1986
18.3 mm (0.7 in)
1987
24.6 mm (1.0 in)
1988
63.5 mm (2.5 in)
1989
39.4 mm (1.6 in)
1990
31.5 mm (1.2 in)
1991
28.7 mm (1.1 in)
1992
25.9 mm (1.0 in)
1993
75.2 mm (3.0 in)
1994
47.5 mm (1.9 in)
1995
50.8 mm (2.0 in)
1996
27.2 mm (1.1 in)
1997
36.3 mm (1.4 in)
1998
35.3 mm (1.4 in)
1999
46.0 mm (1.8 in)
2000
24.9 mm (1.0 in)
2001
42.9 mm (1.7 in)
2004
29.2 mm (1.1 in)
2005
41.9 mm (1.6 in)
2006
21.6 mm (0.9 in)
2007
52.8 mm (2.1 in)
2008
39.9 mm (1.6 in)
2009
64.0 mm (2.5 in)
Wettest five days (Rx5day)
The wettest five days of the year at Alchichica, 1965 to 2009. The record is 181.4 mm (7.1 in) in 1969, marked on the chart; the median year is 63.9 mm (2.5 in).
Wettest five days (Rx5day) at Alchichica by year
Year
Wettest five days (Rx5day)
1965
63.9 mm (2.5 in)
1966
69.8 mm (2.7 in)
1967
72.9 mm (2.9 in)
1968
69.9 mm (2.8 in)
1969
181.4 mm (7.1 in)
1970
78.2 mm (3.1 in)
1971
39.4 mm (1.6 in)
1972
72.2 mm (2.8 in)
1973
62.5 mm (2.5 in)
1974
91.8 mm (3.6 in)
1975
62.6 mm (2.5 in)
1976
62.6 mm (2.5 in)
1977
58.9 mm (2.3 in)
1978
120.5 mm (4.7 in)
1979
71.4 mm (2.8 in)
1980
64.3 mm (2.5 in)
1981
97.8 mm (3.9 in)
1982
52.6 mm (2.1 in)
1983
17.0 mm (0.7 in)
1984
116.7 mm (4.6 in)
1985
45.0 mm (1.8 in)
1986
28.5 mm (1.1 in)
1987
47.1 mm (1.9 in)
1988
96.6 mm (3.8 in)
1989
69.4 mm (2.7 in)
1990
41.7 mm (1.6 in)
1991
92.2 mm (3.6 in)
1992
69.5 mm (2.7 in)
1993
126.5 mm (5.0 in)
1994
59.5 mm (2.3 in)
1995
89.3 mm (3.5 in)
1996
45.8 mm (1.8 in)
1997
54.6 mm (2.1 in)
1998
57.7 mm (2.3 in)
1999
46.5 mm (1.8 in)
2000
51.1 mm (2.0 in)
2001
67.5 mm (2.7 in)
2004
57.4 mm (2.3 in)
2005
70.7 mm (2.8 in)
2006
32.8 mm (1.3 in)
2007
63.0 mm (2.5 in)
2008
62.8 mm (2.5 in)
2009
114.9 mm (4.5 in)
Longest dry spell (CDD)
The longest dry spell of the year at Alchichica, 1965 to 2009. The record is 102 days in 1973, marked on the chart; the median year is 58 days.
Longest dry spell (CDD) at Alchichica by year
Year
Longest dry spell (CDD)
1965
43 days
1966
52 days
1967
52 days
1968
30 days
1969
79 days
1970
83 days
1971
72 days
1972
41 days
1973
102 days
1974
69 days
1975
78 days
1976
55 days
1977
49 days
1978
44 days
1979
53 days
1980
71 days
1981
37 days
1982
60 days
1983
72 days
1984
41 days
1985
54 days
1986
53 days
1987
62 days
1988
90 days
1989
61 days
1990
71 days
1991
102 days
1992
52 days
1993
48 days
1994
102 days
1995
38 days
1996
53 days
1997
74 days
1998
92 days
1999
41 days
2000
69 days
2001
60 days
2004
58 days
2005
31 days
2006
83 days
2007
35 days
2008
65 days
2009
52 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
39 years with a frost
Across 39 years with a frost, the median last spring frost at Alchichica falls on 29 March and the median first autumn frost on 23 October, which leaves a median of 205 days between them.
Fitted over all years, the growing season changes by +7.3 days per decade at this station.
Frost dates and growing season at Alchichica
Measure
Median, all years
Earliest period
Recent period (1976 to 2009)
Recent against earliest
Fitted trend
Last spring frost
29 March
n/a
25 March
n/a
-6.5 days per decade
First autumn frost
23 October
n/a
22 October
n/a
+0.8 days per decade
Growing days
205 days
n/a
208 days
n/a
+7.3 days per decade
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.
Rainfall Return Levels
41 years, 1966 to 2009
A day with at least 37.6 mm (1.5 in) of rain is expected about once in 2 years. A day with at least 111.5 mm (4.4 in) of rain is expected about once in 100 years.
Rainfall return levels at Alchichica: the daily rain expected about once in a given number of years
Expected about once in
A day with at least
Note
2 years
37.6 mm (1.5 in)
5 years
52.7 mm (2.1 in)
10 years
64.4 mm (2.5 in)
25 years
81.3 mm (3.2 in)
50 years
95.6 mm (3.8 in)
Longer than the 41 years of record
100 years
111.5 mm (4.4 in)
Longer than the 41 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, 41 years of values from 1966 to 2009.
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: 129.8 mm (5.1 in) in 1969; 75.2 mm (3.0 in) in 1993; 64.3 mm (2.5 in) in 1978.
Download the Data
Data for Alchichica standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Alchichica 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 2026-10-15 (15 October 2026). Records are computed by this site and are not official.