Dortmund Weather Records (GME00121342)

Record envelope, standing records and threshold days for Dortmund (GME00121342), Germany, with 59 years of record.

Key Facts for Dortmund

Dortmund (GME00121342) is a weather station in Germany at 51.51 latitude and 7.54 longitude, 120 m (394 ft) above sea level.
The station reports from 1941 to 1999, 59 years of record.
1,464 records set at Dortmund still stand.
Records are tracked for tmax, tmin, prcp, snwd: an element needs 30 years of data to be eligible.
Dortmund set a daily record high minimum temperature of 15.5 C (59.9 F) on 24 September 1999.

About the Station

Location: Germany, 51.51 latitude, 7.54 longitude.
Elevation: 120 m (394 ft).
Period of record: 1941 to 1999, 59 years.
Eligible elements: tmax, tmin, prcp, snwd.

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 Dortmund. 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 Dortmund, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	15.6 C (60.1 F)	-19.4 C (-2.9 F)	n/a	n/a
Feb	19.9 C (67.8 F)	-22.4 C (-8.3 F)	n/a	n/a
Mar	24.5 C (76.1 F)	-15.4 C (4.3 F)	n/a	n/a
Apr	30.5 C (86.9 F)	-5.4 C (22.3 F)	n/a	n/a
May	30.7 C (87.3 F)	-2.0 C (28.4 F)	n/a	n/a
Jun	34.2 C (93.6 F)	1.2 C (34.2 F)	n/a	n/a
Jul	35.5 C (95.9 F)	4.0 C (39.2 F)	n/a	n/a
Aug	35.4 C (95.7 F)	3.2 C (37.8 F)	n/a	n/a
Sep	31.5 C (88.7 F)	-0.4 C (31.3 F)	n/a	n/a
Oct	26.6 C (79.9 F)	-5.5 C (22.1 F)	n/a	n/a
Nov	21.3 C (70.3 F)	-11.1 C (12.0 F)	n/a	n/a
Dec	17.0 C (62.6 F)	-17.0 C (1.4 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at Dortmund still stand. 1956 holds the most, with 50.

Standing records at Dortmund by the year they were set
Year set	Standing records
1950	22
1951	24
1952	32
1953	34
1954	34
1955	27
1956	50
1957	47
1958	32
1959	40
1960	27
1961	47
1962	38
1963	29
1964	32
1965	17
1966	23
1967	25
1968	33
1969	36
1970	10
1971	25
1972	28
1973	24
1974	25
1975	16
1976	34
1977	21
1978	21
1979	27
1980	28
1981	28
1982	14
1983	29
1984	21
1985	45
1986	41
1987	42
1988	9
1989	40
1990	37
1991	21
1992	15
1993	40
1994	29
1995	24
1996	33
1997	24
1998	34
1999	30

All-Time Record Progression

3 new records

3 all-time records were set at Dortmund between 31 July 1984 and 5 August 1994. Each dot is a new record.

When Dortmund set new all-time records
Date	Kind	Detail
1984-07-31	Record high minimum temperature	Record high minimum temperature 22.4 C (72.3 F)
1991-07-07	Record high minimum temperature	Record high minimum temperature 22.8 C (73.0 F)
1994-08-05	Record high minimum temperature	Record high minimum temperature 23.0 C (73.4 F)

Wettest Day of Each Month

Jul: 140.0 mm (5.5 in)

The wettest day on record for each calendar month at Dortmund. The most was 140.0 mm (5.5 in) on 31 July 1951.

Record daily precipitation for each month at Dortmund
Month	Record daily precipitation (mm)	Date
Jan	42.9 mm (1.7 in)	29 January 1995
Feb	49.6 mm (2.0 in)	6 February 1984
Mar	35.9 mm (1.4 in)	6 March 1998
Apr	27.0 mm (1.1 in)	29 April 1961
May	51.8 mm (2.0 in)	18 May 1982
Jun	72.7 mm (2.9 in)	15 June 1968
Jul	140.0 mm (5.5 in)	31 July 1951
Aug	72.1 mm (2.8 in)	21 August 1983
Sep	47.5 mm (1.9 in)	4 September 1987
Oct	51.4 mm (2.0 in)	23 October 1982
Nov	38.5 mm (1.5 in)	30 November 1988
Dec	39.2 mm (1.5 in)	3 December 1960

Period of Record Coverage

1950 to 1999

50 years of record at Dortmund, 1950 to 1999. 2 years have data for under 90 percent of days and are left out of rankings: 1975, 1999.

Days with data per year at Dortmund
Year	Days with data	Share of year	Complete
1950	364	100%	Yes
1951	365	100%	Yes
1952	366	100%	Yes
1953	365	100%	Yes
1954	365	100%	Yes
1955	365	100%	Yes
1956	366	100%	Yes
1957	365	100%	Yes
1958	365	100%	Yes
1959	365	100%	Yes
1960	366	100%	Yes
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	366	100%	Yes
1969	365	100%	Yes
1970	365	100%	Yes
1971	365	100%	Yes
1972	366	100%	Yes
1973	365	100%	Yes
1974	365	100%	Yes
1975	304	83%	No
1976	366	100%	Yes
1977	365	100%	Yes
1978	365	100%	Yes
1979	365	100%	Yes
1980	366	100%	Yes
1981	365	100%	Yes
1982	365	100%	Yes
1983	365	100%	Yes
1984	366	100%	Yes
1985	365	100%	Yes
1986	365	100%	Yes
1987	365	100%	Yes
1988	366	100%	Yes
1989	365	100%	Yes
1990	365	100%	Yes
1991	365	100%	Yes
1992	366	100%	Yes
1993	365	100%	Yes
1994	365	100%	Yes
1995	365	100%	Yes
1996	366	100%	Yes
1997	334	92%	Yes
1998	334	92%	Yes
1999	242	66%	No

Latest Records

Latest records at Dortmund
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
24 September 1999	Dortmund, DE	daily high min	15.5 C (59.9 F)	1.0 C (1.8 F)	36 years	18 of 100 (Routine)
23 September 1999	Dortmund, DE	daily high min	16.4 C (61.5 F)	1.4 C (2.5 F)	28 years	17 of 100 (Routine)
15 September 1999	Dortmund, DE	daily high min	16.0 C (60.8 F)	0.8 C (1.4 F)	28 years	15 of 100 (Routine)
14 September 1999	Dortmund, DE	daily high min	17.5 C (63.5 F)	1.9 C (3.4 F)	12 years	14 of 100 (Routine)
13 September 1999	Dortmund, DE	daily high max	31.3 C (88.3 F)	2.8 C (5.0 F)	29 years	20 of 100 (Routine)
12 September 1999	Dortmund, DE	daily high min	16.5 C (61.7 F)	1.0 C (1.8 F)	48 years	22 of 100 (Routine)
12 September 1999	Dortmund, DE	daily high max	30.7 C (87.3 F)	1.0 C (1.8 F)	40 years	19 of 100 (Routine)
11 September 1999	Dortmund, DE	daily high max (Tie)	30.2 C (86.4 F)	tie	40 years	4 of 100 (Routine)
9 September 1999	Dortmund, DE	daily high max	29.0 C (84.2 F)	1.0 C (1.8 F)	25 years	14 of 100 (Routine)
9 September 1999	Dortmund, DE	daily high min	16.0 C (60.8 F)	0.3 C (0.5 F)	17 years	10 of 100 (Routine)
26 August 1999	Dortmund, DE	daily high min	19.3 C (66.7 F)	0.3 C (0.5 F)	6 years	8 of 100 (Routine)
22 August 1999	Dortmund, DE	daily low min	7.2 C (45.0 F)	0.2 C (0.4 F)	25 years	12 of 100 (Routine)
26 June 1999	Dortmund, DE	daily low min	7.0 C (44.6 F)	0.1 C (0.2 F)	41 years	17 of 100 (Routine)
25 June 1999	Dortmund, DE	daily low min	7.3 C (45.1 F)	0.8 C (1.4 F)	34 years	17 of 100 (Routine)
22 June 1999	Dortmund, DE	daily low min	6.9 C (44.4 F)	0.8 C (1.4 F)	37 years	18 of 100 (Routine)
30 May 1999	Dortmund, DE	daily high min	17.2 C (63.0 F)	0.1 C (0.2 F)	20 years	11 of 100 (Routine)
30 May 1999	Dortmund, DE	daily high max	28.8 C (83.8 F)	1.3 C (2.3 F)	2 years	7 of 100 (Routine)
29 May 1999	Dortmund, DE	daily high min	14.5 C (58.1 F)	0.2 C (0.4 F)	4 years	6 of 100 (Routine)
11 May 1999	Dortmund, DE	daily rain	23.4 mm (0.9 in)	14.0 mm (0.6 in)	9 years	20 of 100 (Routine)
10 May 1999	Dortmund, DE	daily rain	17.6 mm (0.7 in)	2.0 mm (0.08 in)	36 years	19 of 100 (Routine)

Climate Trend

46 complete years, 1950 to 1996

One stripe for each of 46 complete years at Dortmund, 1950 to 1996. Blue stripes are years cooler than the station's own mean of 9.7 C (49.5 F); red stripes are warmer. The coolest year was 1956, at 8.1 C (46.6 F), and the warmest was 1989, at 11.2 C (52.2 F). The strongest colour marks a difference of 1.6 C (2.9 F).

Annual mean temperature at Dortmund as warming stripes, 1950 to 1996
Year	Annual mean temperature	Difference from the station mean
1950	9.5 C	-0.23 C
1951	9.9 C	+0.13 C
1952	9.0 C	-0.75 C
1953	10.1 C	+0.37 C
1954	9.0 C	-0.71 C
1955	8.8 C	-0.91 C
1956	8.1 C	-1.60 C
1957	9.8 C	+0.05 C
1958	9.5 C	-0.27 C
1959	10.2 C	+0.51 C
1960	9.8 C	+0.08 C
1961	10.2 C	+0.51 C
1962	8.4 C	-1.30 C
1963	8.3 C	-1.39 C
1964	9.6 C	-0.13 C
1965	9.0 C	-0.75 C
1966	9.8 C	+0.10 C
1967	10.3 C	+0.58 C
1968	9.7 C	-0.07 C
1969	9.6 C	-0.13 C
1970	9.5 C	-0.27 C
1971	10.1 C	+0.32 C
1972	9.5 C	-0.23 C
1973	9.8 C	+0.08 C
1974	10.3 C	+0.52 C
1976	10.2 C	+0.44 C
1977	10.1 C	+0.40 C
1978	9.4 C	-0.32 C
1979	9.2 C	-0.51 C
1980	9.5 C	-0.23 C
1981	9.8 C	+0.08 C
1982	10.7 C	+0.92 C
1983	10.6 C	+0.83 C
1984	9.8 C	+0.04 C
1985	8.8 C	-0.97 C
1986	9.2 C	-0.49 C
1987	9.0 C	-0.73 C
1988	10.6 C	+0.86 C
1989	11.2 C	+1.47 C
1990	11.0 C	+1.25 C
1991	9.8 C	+0.08 C
1992	10.8 C	+1.07 C
1993	9.8 C	+0.06 C
1994	11.0 C	+1.29 C
1995	10.6 C	+0.82 C
1996	8.7 C	-1.01 C

The annual mean temperature here has risen by 0.2 C (0.1 to 0.4) per decade over 1950 to 1996. In Fahrenheit: 0.4 F (0.1 to 0.6) per decade. The slope is a straight line fitted to 46 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at Dortmund
Measure	Per decade (C)	Per decade (F)	Period	Complete years	Reading
Annual mean temperature	0.2 C (0.1 to 0.4) per decade	0.4 F (0.1 to 0.6) per decade	1950 to 1996	46	Rise
Mean daily maximum	0.15 C (-0.02 to 0.33) per decade	0.28 F (-0.05 to 0.60) per decade	1950 to 1996	46	Not clearly different from zero
Mean daily minimum	0.3 C (0.1 to 0.4) per decade	0.5 F (0.2 to 0.7) per decade	1950 to 1996	46	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

1941 to 1999

Yearly extremes at Dortmund: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	35.5 C (95.9 F)	1959	32.1 C (89.7 F)	50
Coldest night (TNn)	-22.4 C (-8.3 F)	1956	-12.8 C (9.0 F)	50
Wettest day (Rx1day)	140.0 mm (5.5 in)	1951	34.2 mm (1.3 in)	57
Wettest five days (Rx5day)	154.3 mm (6.1 in)	1951	59.6 mm (2.3 in)	57
Longest dry spell (CDD)	35 days	1968	20 days	57

Hottest day (TXx)

The hottest day of the year at Dortmund, 1941 to 1999. The record is 35.5 C (95.9 F) in 1959, marked on the chart; the median year is 32.1 C (89.7 F).

Hottest day (TXx) at Dortmund by year
Year	Hottest day (TXx)
1941	n/a
1942	n/a
1943	n/a
1944	n/a
1947	n/a
1948	n/a
1949	n/a
1950	32.0 C (89.6 F)
1951	30.6 C (87.1 F)
1952	35.3 C (95.5 F)
1953	31.8 C (89.2 F)
1954	29.7 C (85.5 F)
1955	31.6 C (88.9 F)
1956	29.5 C (85.1 F)
1957	35.1 C (95.2 F)
1958	30.3 C (86.5 F)
1959	35.5 C (95.9 F)
1960	29.5 C (85.1 F)
1961	33.2 C (91.8 F)
1962	29.6 C (85.3 F)
1963	33.0 C (91.4 F)
1964	34.8 C (94.6 F)
1965	28.0 C (82.4 F)
1966	32.5 C (90.5 F)
1967	31.0 C (87.8 F)
1968	32.0 C (89.6 F)
1969	32.2 C (90.0 F)
1970	30.5 C (86.9 F)
1971	30.5 C (86.9 F)
1972	32.4 C (90.3 F)
1973	32.5 C (90.5 F)
1974	32.8 C (91.0 F)
1975	32.1 C (89.8 F)
1976	34.3 C (93.7 F)
1977	30.3 C (86.5 F)
1978	31.7 C (89.1 F)
1979	31.5 C (88.7 F)
1980	30.7 C (87.3 F)
1981	31.1 C (88.0 F)
1982	31.2 C (88.2 F)
1983	34.0 C (93.2 F)
1984	32.6 C (90.7 F)
1985	31.9 C (89.4 F)
1986	34.3 C (93.7 F)
1987	32.2 C (90.0 F)
1988	29.4 C (84.9 F)
1989	31.2 C (88.2 F)
1990	35.4 C (95.7 F)
1991	33.6 C (92.5 F)
1992	33.0 C (91.4 F)
1993	29.4 C (84.9 F)
1994	34.8 C (94.6 F)
1995	34.5 C (94.1 F)
1996	33.2 C (91.8 F)
1997	33.0 C (91.4 F)
1998	33.0 C (91.4 F)
1999	31.3 C (88.3 F)

Coldest night (TNn)

The coldest night of the year at Dortmund, 1941 to 1999. The record is -22.4 C (-8.3 F) in 1956, marked on the chart; the median year is -12.8 C (9.0 F).

Coldest night (TNn) at Dortmund by year
Year	Coldest night (TNn)
1941	n/a
1942	n/a
1943	n/a
1944	n/a
1947	n/a
1948	n/a
1949	n/a
1950	-17.0 C (1.4 F)
1951	-6.2 C (20.8 F)
1952	-7.4 C (18.7 F)
1953	-14.5 C (5.9 F)
1954	-15.6 C (3.9 F)
1955	-15.0 C (5.0 F)
1956	-22.4 C (-8.3 F)
1957	-13.8 C (7.2 F)
1958	-15.4 C (4.3 F)
1959	-8.7 C (16.3 F)
1960	-19.4 C (-2.9 F)
1961	-13.9 C (7.0 F)
1962	-13.9 C (7.0 F)
1963	-17.6 C (0.3 F)
1964	-10.4 C (13.3 F)
1965	-8.5 C (16.7 F)
1966	-13.8 C (7.2 F)
1967	-9.3 C (15.3 F)
1968	-16.4 C (2.5 F)
1969	-11.7 C (10.9 F)
1970	-11.5 C (11.3 F)
1971	-14.0 C (6.8 F)
1972	-12.5 C (9.5 F)
1973	-12.3 C (9.9 F)
1974	-4.3 C (24.3 F)
1975	-7.5 C (18.5 F)
1976	-11.1 C (12.0 F)
1977	-7.4 C (18.7 F)
1978	-16.4 C (2.5 F)
1979	-19.0 C (-2.2 F)
1980	-10.2 C (13.6 F)
1981	-13.1 C (8.4 F)
1982	-16.8 C (1.8 F)
1983	-10.1 C (13.8 F)
1984	-6.7 C (19.9 F)
1985	-18.6 C (-1.5 F)
1986	-17.2 C (1.0 F)
1987	-18.3 C (-0.9 F)
1988	-7.5 C (18.5 F)
1989	-7.8 C (18.0 F)
1990	-4.6 C (23.7 F)
1991	-13.6 C (7.5 F)
1992	-8.9 C (16.0 F)
1993	-13.1 C (8.4 F)
1994	-11.4 C (11.5 F)
1995	-10.6 C (12.9 F)
1996	-13.2 C (8.2 F)
1997	-16.8 C (1.8 F)
1998	-9.1 C (15.6 F)
1999	-10.8 C (12.6 F)

Wettest day (Rx1day)

The wettest day of the year at Dortmund, 1941 to 1999. The record is 140.0 mm (5.5 in) in 1951, marked on the chart; the median year is 34.2 mm (1.3 in).

Wettest day (Rx1day) at Dortmund by year
Year	Wettest day (Rx1day)
1941	41.6 mm (1.6 in)
1942	31.5 mm (1.2 in)
1943	24.0 mm (0.9 in)
1944	31.5 mm (1.2 in)
1947	25.8 mm (1.0 in)
1948	43.9 mm (1.7 in)
1949	45.9 mm (1.8 in)
1950	21.6 mm (0.9 in)
1951	140.0 mm (5.5 in)
1952	35.2 mm (1.4 in)
1953	26.6 mm (1.0 in)
1954	35.1 mm (1.4 in)
1955	17.7 mm (0.7 in)
1956	53.0 mm (2.1 in)
1957	25.7 mm (1.0 in)
1958	27.6 mm (1.1 in)
1959	16.1 mm (0.6 in)
1960	39.2 mm (1.5 in)
1961	45.9 mm (1.8 in)
1962	27.5 mm (1.1 in)
1963	25.7 mm (1.0 in)
1964	42.0 mm (1.7 in)
1965	61.0 mm (2.4 in)
1966	34.0 mm (1.3 in)
1967	26.7 mm (1.1 in)
1968	72.7 mm (2.9 in)
1969	22.9 mm (0.9 in)
1970	28.6 mm (1.1 in)
1971	34.2 mm (1.3 in)
1972	34.9 mm (1.4 in)
1973	21.4 mm (0.8 in)
1974	28.3 mm (1.1 in)
1975	27.5 mm (1.1 in)
1976	30.1 mm (1.2 in)
1977	18.4 mm (0.7 in)
1978	27.6 mm (1.1 in)
1979	30.3 mm (1.2 in)
1980	35.0 mm (1.4 in)
1981	54.7 mm (2.2 in)
1982	51.8 mm (2.0 in)
1983	72.1 mm (2.8 in)
1984	49.6 mm (2.0 in)
1985	21.5 mm (0.8 in)
1986	27.0 mm (1.1 in)
1987	47.5 mm (1.9 in)
1988	38.5 mm (1.5 in)
1989	19.3 mm (0.8 in)
1990	68.0 mm (2.7 in)
1991	35.4 mm (1.4 in)
1992	29.0 mm (1.1 in)
1993	34.2 mm (1.3 in)
1994	48.7 mm (1.9 in)
1995	48.9 mm (1.9 in)
1996	44.7 mm (1.8 in)
1997	35.4 mm (1.4 in)
1998	42.0 mm (1.7 in)
1999	23.4 mm (0.9 in)

Wettest five days (Rx5day)

The wettest five days of the year at Dortmund, 1941 to 1999. The record is 154.3 mm (6.1 in) in 1951, marked on the chart; the median year is 59.6 mm (2.3 in).

Wettest five days (Rx5day) at Dortmund by year
Year	Wettest five days (Rx5day)
1941	63.9 mm (2.5 in)
1942	57.5 mm (2.3 in)
1943	44.7 mm (1.8 in)
1944	62.1 mm (2.4 in)
1947	50.1 mm (2.0 in)
1948	56.8 mm (2.2 in)
1949	73.2 mm (2.9 in)
1950	46.0 mm (1.8 in)
1951	154.3 mm (6.1 in)
1952	75.0 mm (3.0 in)
1953	45.0 mm (1.8 in)
1954	61.5 mm (2.4 in)
1955	47.8 mm (1.9 in)
1956	83.0 mm (3.3 in)
1957	60.1 mm (2.4 in)
1958	48.0 mm (1.9 in)
1959	32.3 mm (1.3 in)
1960	73.8 mm (2.9 in)
1961	67.4 mm (2.7 in)
1962	55.6 mm (2.2 in)
1963	48.3 mm (1.9 in)
1964	47.0 mm (1.9 in)
1965	88.9 mm (3.5 in)
1966	55.6 mm (2.2 in)
1967	56.9 mm (2.2 in)
1968	106.9 mm (4.2 in)
1969	54.9 mm (2.2 in)
1970	54.7 mm (2.2 in)
1971	57.8 mm (2.3 in)
1972	51.7 mm (2.0 in)
1973	50.0 mm (2.0 in)
1974	59.6 mm (2.3 in)
1975	44.9 mm (1.8 in)
1976	46.1 mm (1.8 in)
1977	38.9 mm (1.5 in)
1978	59.2 mm (2.3 in)
1979	59.0 mm (2.3 in)
1980	65.9 mm (2.6 in)
1981	91.5 mm (3.6 in)
1982	61.0 mm (2.4 in)
1983	79.9 mm (3.1 in)
1984	85.0 mm (3.3 in)
1985	58.9 mm (2.3 in)
1986	81.4 mm (3.2 in)
1987	76.5 mm (3.0 in)
1988	60.7 mm (2.4 in)
1989	47.1 mm (1.9 in)
1990	81.8 mm (3.2 in)
1991	77.3 mm (3.0 in)
1992	64.2 mm (2.5 in)
1993	65.0 mm (2.6 in)
1994	68.7 mm (2.7 in)
1995	100.1 mm (3.9 in)
1996	57.1 mm (2.2 in)
1997	60.3 mm (2.4 in)
1998	91.3 mm (3.6 in)
1999	43.8 mm (1.7 in)

Longest dry spell (CDD)

The longest dry spell of the year at Dortmund, 1941 to 1999. The record is 35 days in 1968, marked on the chart; the median year is 20 days.

Longest dry spell (CDD) at Dortmund by year
Year	Longest dry spell (CDD)
1941	13 days
1942	20 days
1943	19 days
1944	18 days
1947	24 days
1948	22 days
1949	18 days
1950	14 days
1951	27 days
1952	14 days
1953	25 days
1954	19 days
1955	11 days
1956	27 days
1957	14 days
1958	14 days
1959	30 days
1960	15 days
1961	22 days
1962	28 days
1963	20 days
1964	20 days
1965	12 days
1966	15 days
1967	16 days
1968	35 days
1969	20 days
1970	12 days
1971	20 days
1972	23 days
1973	24 days
1974	22 days
1975	21 days
1976	25 days
1977	16 days
1978	18 days
1979	14 days
1980	20 days
1981	23 days
1982	16 days
1983	17 days
1984	24 days
1985	21 days
1986	22 days
1987	12 days
1988	15 days
1989	20 days
1990	22 days
1991	25 days
1992	21 days
1993	19 days
1994	17 days
1995	21 days
1996	23 days
1997	20 days
1998	18 days
1999	18 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

46 years with a frost

Across 46 years with a frost, the median last spring frost at Dortmund falls on 20 April and the median first autumn frost on 2 November, which leaves a median of 199 days between them.

Fitted over all years, the growing season changes by +6.7 days per decade at this station.

Frost dates and growing season at Dortmund
Measure	Median, all years	Earliest period	Recent period (1966 to 1996)	Recent against earliest	Fitted trend
Last spring frost	20 April	n/a	17 April	n/a	-5.0 days per decade
First autumn frost	2 November	n/a	6 November	n/a	+1.7 days per decade
Growing days	199 days	n/a	204 days	n/a	+6.7 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

56 years, 1941 to 1998

A day with at least 33.2 mm (1.3 in) of rain is expected about once in 2 years. A day with at least 110.0 mm (4.3 in) of rain is expected about once in 100 years.

Rainfall return levels at Dortmund: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	33.2 mm (1.3 in)
5 years	47.2 mm (1.9 in)
10 years	58.7 mm (2.3 in)
25 years	76.2 mm (3.0 in)
50 years	91.9 mm (3.6 in)
100 years	110.0 mm (4.3 in)	Longer than the 56 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, 56 years of values from 1941 to 1998.

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: 140.0 mm (5.5 in) in 1951; 72.7 mm (2.9 in) in 1968; 72.1 mm (2.8 in) in 1983.

Station Changes

2 suspected

2 changes were suspected in the annual mean temperature of Dortmund, at 1960 and 1985. Each is measured against neighbouring stations.

Relative to 5 neighbouring stations, the station's annual mean temperature from 1960 ran 0.1 C (0.2 F) higher than in the years before (possible change).
Relative to 5 neighbouring stations, the station's annual mean temperature from 1985 ran 0.1 C (0.2 F) lower than in the years before (likely change).

Suspected changes in the annual mean temperature at Dortmund, against neighbouring stations
Year	Shift (C)	Shift (F)	Strength	Neighbours
1960	+0.1	+0.2	possible	5
1985	-0.1	-0.2	likely	5

Possible change at the station (a move, a new instrument or a new site); the record is kept as measured. A "likely" change has a larger test statistic than a "possible" one. Neither says why the station differs from its neighbours. How changes are found, and the largest ones.

Download the Data

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