Atlacomulco I (Dge) Weather Records (MXN00015139)

Record envelope, standing records and threshold days for Atlacomulco I (Dge) (MXN00015139), Mexico, with 34 years of record.

Key Facts for Atlacomulco I (Dge)

Atlacomulco I (Dge) (MXN00015139) is a weather station in Mexico at 19.78 latitude and -99.87 longitude, 2,550 m (8,366 ft) above sea level.
The station reports from 1961 to 1994, 34 years of record.
1,464 records set at Atlacomulco I (Dge) still stand.
Records are tracked for tmax, tmin, prcp: an element needs 30 years of data to be eligible.
Atlacomulco I (Dge) tied a daily record high maximum temperature of 22.8 C (73.0 F) on 27 July 1994.

About the Station

Location: Mexico, 19.78 latitude, -99.87 longitude.
Elevation: 2,550 m (8,366 ft).
Period of record: 1961 to 1994, 34 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 Atlacomulco I (Dge). 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 Atlacomulco I (Dge), with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	27.2 C (81.0 F)	-11.7 C (10.9 F)	n/a	n/a
Feb	27.2 C (81.0 F)	-9.4 C (15.1 F)	n/a	n/a
Mar	31.7 C (89.1 F)	-5.6 C (21.9 F)	n/a	n/a
Apr	31.7 C (89.1 F)	-3.3 C (26.1 F)	n/a	n/a
May	32.8 C (91.0 F)	0.6 C (33.1 F)	n/a	n/a
Jun	30.0 C (86.0 F)	1.1 C (34.0 F)	n/a	n/a
Jul	27.2 C (81.0 F)	0.6 C (33.1 F)	n/a	n/a
Aug	25.6 C (78.1 F)	0.0 C (32.0 F)	n/a	n/a
Sep	26.1 C (79.0 F)	-2.2 C (28.0 F)	n/a	n/a
Oct	28.9 C (84.0 F)	-5.0 C (23.0 F)	n/a	n/a
Nov	26.1 C (79.0 F)	-10.0 C (14.0 F)	n/a	n/a
Dec	25.6 C (78.1 F)	-10.0 C (14.0 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at Atlacomulco I (Dge) still stand. 1980 holds the most, with 83.

Standing records at Atlacomulco I (Dge) by the year they were set
Year set	Standing records
1961	65
1962	47
1963	44
1964	44
1965	41
1966	59
1967	55
1968	42
1969	47
1970	45
1971	39
1972	51
1973	43
1974	45
1975	26
1976	41
1977	45
1978	50
1979	82
1980	83
1981	66
1982	39
1983	58
1984	33
1985	31
1986	42
1987	48
1988	46
1989	30
1990	35
1991	10
1992	29
1994	3

Wettest Day of Each Month

Jun: 65.5 mm (2.6 in)

The wettest day on record for each calendar month at Atlacomulco I (Dge). The most was 65.5 mm (2.6 in) on 20 June 1981.

Record daily precipitation for each month at Atlacomulco I (Dge)
Month	Record daily precipitation (mm)	Date
Jan	41.7 mm (1.6 in)	28 January 1992
Feb	27.4 mm (1.1 in)	2 February 1992
Mar	35.8 mm (1.4 in)	4 March 1988
Apr	27.2 mm (1.1 in)	29 April 1967
May	52.1 mm (2.1 in)	27 May 1964
Jun	65.5 mm (2.6 in)	20 June 1981
Jul	65.3 mm (2.6 in)	4 July 1974
Aug	59.9 mm (2.4 in)	18 August 1961
Sep	58.9 mm (2.3 in)	23 September 1967
Oct	51.6 mm (2.0 in)	11 October 1976
Nov	42.7 mm (1.7 in)	11 November 1964
Dec	29.5 mm (1.2 in)	2 December 1971

Period of Record Coverage

1961 to 1994

33 years of record at Atlacomulco I (Dge), 1961 to 1994. 3 years have data for under 90 percent of days and are left out of rankings: 1991, 1992, 1994.

Days with data per year at Atlacomulco I (Dge)
Year	Days with data	Share of year	Complete
1961	365	100%	Yes
1962	365	100%	Yes
1963	365	100%	Yes
1964	366	100%	Yes
1965	365	100%	Yes
1966	365	100%	Yes
1967	365	100%	Yes
1968	365	100%	Yes
1969	338	93%	Yes
1970	364	100%	Yes
1971	365	100%	Yes
1972	366	100%	Yes
1973	365	100%	Yes
1974	365	100%	Yes
1975	365	100%	Yes
1976	366	100%	Yes
1977	365	100%	Yes
1978	364	100%	Yes
1979	365	100%	Yes
1980	366	100%	Yes
1981	365	100%	Yes
1982	365	100%	Yes
1983	362	99%	Yes
1984	362	99%	Yes
1985	365	100%	Yes
1986	365	100%	Yes
1987	354	97%	Yes
1988	364	99%	Yes
1989	360	99%	Yes
1990	333	91%	Yes
1991	310	85%	No
1992	287	78%	No
1994	58	16%	No

Latest Records

Latest records at Atlacomulco I (Dge)
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
27 July 1994	Atlacomulco I (Dge), MX	daily high max (Tie)	22.8 C (73.0 F)	tie	12 years	1 of 100 (Routine)
18 July 1994	Atlacomulco I (Dge), MX	daily low min	5.0 C (41.0 F)	0.6 C (1.1 F)	27 years	14 of 100 (Routine)
24 June 1994	Atlacomulco I (Dge), MX	daily low max (Tie)	17.8 C (64.0 F)	tie	32 years	3 of 100 (Routine)
23 June 1994	Atlacomulco I (Dge), MX	daily rain	44.2 mm (1.7 in)	15.2 mm (0.6 in)	16 years	23 of 100 (Routine)
20 June 1994	Atlacomulco I (Dge), MX	daily low max	16.7 C (62.1 F)	0.5 C (0.9 F)	16 years	9 of 100 (Routine)
14 June 1994	Atlacomulco I (Dge), MX	daily low max (Tie)	18.9 C (66.0 F)	tie	32 years	3 of 100 (Routine)
10 June 1994	Atlacomulco I (Dge), MX	daily high min	11.7 C (53.1 F)	1.1 C (2.0 F)	32 years	17 of 100 (Routine)
24 October 1992	Atlacomulco I (Dge), MX	daily high min	8.9 C (48.0 F)	1.1 C (2.0 F)	16 years	10 of 100 (Routine)
11 October 1992	Atlacomulco I (Dge), MX	daily high min (Tie)	10.0 C (50.0 F)	tie	20 years	2 of 100 (Routine)
29 September 1992	Atlacomulco I (Dge), MX	daily low max	15.6 C (60.1 F)	2.2 C (4.0 F)	23 years	20 of 100 (Routine)
28 September 1992	Atlacomulco I (Dge), MX	daily low max	15.6 C (60.1 F)	1.1 C (2.0 F)	3 years	8 of 100 (Routine)
28 September 1992	Atlacomulco I (Dge), MX	daily high min (Tie)	10.6 C (51.1 F)	tie	12 years	1 of 100 (Routine)
24 September 1992	Atlacomulco I (Dge), MX	daily low max (Tie)	16.7 C (62.1 F)	tie	25 years	2 of 100 (Routine)
16 September 1992	Atlacomulco I (Dge), MX	daily rain	27.9 mm (1.1 in)	10.6 mm (0.4 in)	28 years	23 of 100 (Routine)
26 August 1992	Atlacomulco I (Dge), MX	monthly high max (Tie)	25.6 C (78.1 F)	tie	11 years	4 of 100 (Routine)
20 August 1992	Atlacomulco I (Dge), MX	daily high max (Tie)	22.8 C (73.0 F)	tie	13 years	1 of 100 (Routine)
27 July 1992	Atlacomulco I (Dge), MX	daily low max (Tie)	18.3 C (64.9 F)	tie	29 years	2 of 100 (Routine)
8 July 1992	Atlacomulco I (Dge), MX	daily high max (Tie)	23.9 C (75.0 F)	tie	20 years	2 of 100 (Routine)
5 July 1992	Atlacomulco I (Dge), MX	daily low max (Tie)	18.9 C (66.0 F)	tie	28 years	2 of 100 (Routine)
2 July 1992	Atlacomulco I (Dge), MX	monthly high max	27.2 C (81.0 F)	0.5 C (0.9 F)	13 years	18 of 100 (Routine)

Climate Trend

28 complete years, 1961 to 1989

One stripe for each of 28 complete years at Atlacomulco I (Dge), 1961 to 1989. Blue stripes are years cooler than the station's own mean of 13.2 C (55.7 F); red stripes are warmer. The coolest year was 1968, at 12.2 C (54.0 F), and the warmest was 1980, at 14.2 C (57.6 F). The strongest colour marks a difference of 1.1 C (2.0 F).

Annual mean temperature at Atlacomulco I (Dge) as warming stripes, 1961 to 1989
Year	Annual mean temperature	Difference from the station mean
1961	13.3 C	+0.07 C
1962	12.9 C	-0.32 C
1963	12.7 C	-0.53 C
1964	13.0 C	-0.23 C
1965	12.5 C	-0.66 C
1966	12.3 C	-0.94 C
1967	12.5 C	-0.73 C
1968	12.2 C	-0.97 C
1970	12.4 C	-0.83 C
1971	12.2 C	-0.95 C
1972	12.8 C	-0.39 C
1973	13.0 C	-0.21 C
1974	13.0 C	-0.15 C
1975	12.9 C	-0.30 C
1976	13.2 C	+0.03 C
1977	13.2 C	-0.02 C
1978	13.8 C	+0.64 C
1979	14.0 C	+0.77 C
1980	14.2 C	+1.04 C
1981	14.0 C	+0.83 C
1982	13.9 C	+0.75 C
1983	13.6 C	+0.43 C
1984	13.6 C	+0.41 C
1985	14.1 C	+0.86 C
1986	13.5 C	+0.30 C
1987	13.6 C	+0.42 C
1988	13.5 C	+0.31 C
1989	13.6 C	+0.38 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

1961 to 1994

Yearly extremes at Atlacomulco I (Dge): the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	32.8 C (91.0 F)	1978	29.4 C (84.9 F)	33
Coldest night (TNn)	-11.7 C (10.9 F)	1988	-6.1 C (21.0 F)	33
Wettest day (Rx1day)	65.5 mm (2.6 in)	1981	41.1 mm (1.6 in)	33
Wettest five days (Rx5day)	149.9 mm (5.9 in)	1974	89.3 mm (3.5 in)	33
Longest dry spell (CDD)	103 days	1986	45 days	33

Hottest day (TXx)

The hottest day of the year at Atlacomulco I (Dge), 1961 to 1994. The record is 32.8 C (91.0 F) in 1978, marked on the chart; the median year is 29.4 C (84.9 F).

Hottest day (TXx) at Atlacomulco I (Dge) by year
Year	Hottest day (TXx)
1961	30.0 C (86.0 F)
1962	28.9 C (84.0 F)
1963	27.8 C (82.0 F)
1964	30.0 C (86.0 F)
1965	27.8 C (82.0 F)
1966	28.9 C (84.0 F)
1967	29.4 C (84.9 F)
1968	27.8 C (82.0 F)
1969	28.9 C (84.0 F)
1970	30.0 C (86.0 F)
1971	30.0 C (86.0 F)
1972	27.2 C (81.0 F)
1973	30.0 C (86.0 F)
1974	29.4 C (84.9 F)
1975	30.0 C (86.0 F)
1976	28.9 C (84.0 F)
1977	31.7 C (89.1 F)
1978	32.8 C (91.0 F)
1979	31.1 C (88.0 F)
1980	31.7 C (89.1 F)
1981	28.9 C (84.0 F)
1982	30.6 C (87.1 F)
1983	30.6 C (87.1 F)
1984	29.4 C (84.9 F)
1985	28.9 C (84.0 F)
1986	28.9 C (84.0 F)
1987	28.3 C (82.9 F)
1988	30.0 C (86.0 F)
1989	30.0 C (86.0 F)
1990	28.9 C (84.0 F)
1991	28.9 C (84.0 F)
1992	27.2 C (81.0 F)
1994	25.6 C (78.1 F)

Coldest night (TNn)

The coldest night of the year at Atlacomulco I (Dge), 1961 to 1994. The record is -11.7 C (10.9 F) in 1988, marked on the chart; the median year is -6.1 C (21.0 F).

Coldest night (TNn) at Atlacomulco I (Dge) by year
Year	Coldest night (TNn)
1961	-10.0 C (14.0 F)
1962	-7.8 C (18.0 F)
1963	-10.0 C (14.0 F)
1964	-2.8 C (27.0 F)
1965	-7.8 C (18.0 F)
1966	-11.1 C (12.0 F)
1967	-8.3 C (17.1 F)
1968	-8.3 C (17.1 F)
1969	-7.2 C (19.0 F)
1970	-9.4 C (15.1 F)
1971	-6.1 C (21.0 F)
1972	-8.3 C (17.1 F)
1973	-6.1 C (21.0 F)
1974	-6.1 C (21.0 F)
1975	-7.8 C (18.0 F)
1976	-7.2 C (19.0 F)
1977	-4.4 C (24.1 F)
1978	-3.9 C (25.0 F)
1979	-6.1 C (21.0 F)
1980	-6.7 C (19.9 F)
1981	-5.0 C (23.0 F)
1982	-5.6 C (21.9 F)
1983	-6.1 C (21.0 F)
1984	-3.3 C (26.1 F)
1985	-3.9 C (25.0 F)
1986	-7.2 C (19.0 F)
1987	-5.6 C (21.9 F)
1988	-11.7 C (10.9 F)
1989	-3.3 C (26.1 F)
1990	-6.1 C (21.0 F)
1991	-5.0 C (23.0 F)
1992	-3.9 C (25.0 F)
1994	5.0 C (41.0 F)

Wettest day (Rx1day)

The wettest day of the year at Atlacomulco I (Dge), 1961 to 1994. The record is 65.5 mm (2.6 in) in 1981, marked on the chart; the median year is 41.1 mm (1.6 in).

Wettest day (Rx1day) at Atlacomulco I (Dge) by year
Year	Wettest day (Rx1day)
1961	59.9 mm (2.4 in)
1962	48.3 mm (1.9 in)
1963	56.6 mm (2.2 in)
1964	52.1 mm (2.1 in)
1965	37.3 mm (1.5 in)
1966	40.4 mm (1.6 in)
1967	58.9 mm (2.3 in)
1968	37.8 mm (1.5 in)
1969	38.4 mm (1.5 in)
1970	60.7 mm (2.4 in)
1971	36.3 mm (1.4 in)
1972	35.8 mm (1.4 in)
1973	46.2 mm (1.8 in)
1974	65.3 mm (2.6 in)
1975	44.5 mm (1.8 in)
1976	51.6 mm (2.0 in)
1977	33.8 mm (1.3 in)
1978	37.1 mm (1.5 in)
1979	32.3 mm (1.3 in)
1980	34.0 mm (1.3 in)
1981	65.5 mm (2.6 in)
1982	39.9 mm (1.6 in)
1983	43.7 mm (1.7 in)
1984	59.9 mm (2.4 in)
1985	37.8 mm (1.5 in)
1986	37.6 mm (1.5 in)
1987	41.1 mm (1.6 in)
1988	47.8 mm (1.9 in)
1989	40.4 mm (1.6 in)
1990	34.8 mm (1.4 in)
1991	35.8 mm (1.4 in)
1992	41.7 mm (1.6 in)
1994	44.2 mm (1.7 in)

Wettest five days (Rx5day)

The wettest five days of the year at Atlacomulco I (Dge), 1961 to 1994. The record is 149.9 mm (5.9 in) in 1974, marked on the chart; the median year is 89.3 mm (3.5 in).

Wettest five days (Rx5day) at Atlacomulco I (Dge) by year
Year	Wettest five days (Rx5day)
1961	66.5 mm (2.6 in)
1962	129.8 mm (5.1 in)
1963	105.7 mm (4.2 in)
1964	89.9 mm (3.5 in)
1965	110.1 mm (4.3 in)
1966	115.3 mm (4.5 in)
1967	96.8 mm (3.8 in)
1968	89.3 mm (3.5 in)
1969	121.0 mm (4.8 in)
1970	114.8 mm (4.5 in)
1971	85.2 mm (3.4 in)
1972	74.8 mm (2.9 in)
1973	93.9 mm (3.7 in)
1974	149.9 mm (5.9 in)
1975	83.5 mm (3.3 in)
1976	106.5 mm (4.2 in)
1977	88.5 mm (3.5 in)
1978	77.2 mm (3.0 in)
1979	55.8 mm (2.2 in)
1980	79.2 mm (3.1 in)
1981	110.0 mm (4.3 in)
1982	87.4 mm (3.4 in)
1983	96.2 mm (3.8 in)
1984	111.0 mm (4.4 in)
1985	73.8 mm (2.9 in)
1986	81.4 mm (3.2 in)
1987	127.9 mm (5.0 in)
1988	69.2 mm (2.7 in)
1989	70.6 mm (2.8 in)
1990	57.7 mm (2.3 in)
1991	62.2 mm (2.4 in)
1992	75.8 mm (3.0 in)
1994	104.2 mm (4.1 in)

Longest dry spell (CDD)

The longest dry spell of the year at Atlacomulco I (Dge), 1961 to 1994. The record is 103 days in 1986, marked on the chart; the median year is 45 days.

Longest dry spell (CDD) at Atlacomulco I (Dge) by year
Year	Longest dry spell (CDD)
1961	55 days
1962	66 days
1963	57 days
1964	42 days
1965	45 days
1966	34 days
1967	32 days
1968	27 days
1969	52 days
1970	45 days
1971	73 days
1972	32 days
1973	94 days
1974	37 days
1975	70 days
1976	37 days
1977	30 days
1978	26 days
1979	37 days
1980	30 days
1981	31 days
1982	79 days
1983	72 days
1984	87 days
1985	31 days
1986	103 days
1987	51 days
1988	61 days
1989	54 days
1990	27 days
1991	85 days
1992	32 days
1994	5 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

28 years with a frost

Across 28 years with a frost, the median last spring frost at Atlacomulco I (Dge) falls on 20 March and the median first autumn frost on 21 October, which leaves a median of 213 days between them.

Fitted over all years, the growing season changes by +10.4 days per decade at this station.

Frost dates and growing season at Atlacomulco I (Dge)
Measure	Median, all years	Earliest period	Recent period (1961 to 1989)	Recent against earliest	Fitted trend
Last spring frost	20 March	n/a	20 March	n/a	-11.3 days per decade
First autumn frost	21 October	n/a	21 October	n/a	-1.0 days per decade
Growing days	213 days	n/a	213 days	n/a	+10.4 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

30 years, 1961 to 1990

A day with at least 43.0 mm (1.7 in) of rain is expected about once in 2 years. A day with at least 82.8 mm (3.3 in) of rain is expected about once in 100 years.

Rainfall return levels at Atlacomulco I (Dge): the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	43.0 mm (1.7 in)
5 years	52.4 mm (2.1 in)
10 years	59.1 mm (2.3 in)
25 years	68.1 mm (2.7 in)
50 years	75.3 mm (3.0 in)	Longer than the 30 years of record
100 years	82.8 mm (3.3 in)	Longer than the 30 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, 30 years of values from 1961 to 1990.

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: 65.5 mm (2.6 in) in 1981; 65.3 mm (2.6 in) in 1974; 60.7 mm (2.4 in) in 1970.

Download the Data

Data for Atlacomulco I (Dge) standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Atlacomulco I (Dge) 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).