Heidelberg Weather Records (USC00153741)

Record envelope, standing records and threshold days for Heidelberg (USC00153741), Kentucky, United States, with 76 years of record.

Key Facts for Heidelberg

Heidelberg (USC00153741) is a weather station in Kentucky, United States at 37.55 latitude and -83.77 longitude, 203 m (665 ft) above sea level.
The station reports from 1932 to 2007, 76 years of record.
1,464 records set at Heidelberg still stand.
Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
Heidelberg set a daily record precipitation of 67.3 mm (2.6 in) on 24 October 2007.

About the Station

Location: Kentucky, United States, 37.55 latitude, -83.77 longitude.
Elevation: 203 m (665 ft).
Period of record: 1932 to 2007, 76 years.
Eligible elements: tmax, tmin, prcp, snow, 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 Heidelberg. 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 Heidelberg, 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)	-32.8 C (-27.0 F)	n/a	n/a
Feb	27.2 C (81.0 F)	-27.8 C (-18.0 F)	n/a	n/a
Mar	30.6 C (87.1 F)	-22.8 C (-9.0 F)	n/a	n/a
Apr	34.4 C (93.9 F)	-7.8 C (18.0 F)	n/a	n/a
May	37.2 C (99.0 F)	-2.8 C (27.0 F)	n/a	n/a
Jun	40.0 C (104.0 F)	0.6 C (33.1 F)	n/a	n/a
Jul	40.6 C (105.1 F)	6.7 C (44.1 F)	n/a	n/a
Aug	40.6 C (105.1 F)	3.9 C (39.0 F)	n/a	n/a
Sep	38.3 C (100.9 F)	0.0 C (32.0 F)	n/a	n/a
Oct	34.4 C (93.9 F)	-9.4 C (15.1 F)	n/a	n/a
Nov	29.4 C (84.9 F)	-16.7 C (1.9 F)	n/a	n/a
Dec	27.8 C (82.0 F)	-26.1 C (-15.0 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at Heidelberg still stand. 1936 holds the most, with 44.

Standing records at Heidelberg by the year they were set
Year set	Standing records
1933	14
1934	35
1935	24
1936	44
1937	29
1938	21
1939	29
1940	31
1941	32
1942	25
1943	29
1944	18
1945	24
1946	19
1947	23
1948	14
1949	15
1950	22
1951	19
1952	25
1953	41
1954	29
1955	16
1956	17
1957	14
1958	12
1959	20
1960	22
1961	19
1962	27
1963	31
1964	19
1965	19
1966	23
1967	25
1968	11
1969	16
1970	15
1971	17
1972	13
1973	12
1974	18
1975	12
1976	18
1977	8
1978	5
1979	6
1980	7
1981	1
1982	14
1983	19
1984	32
1985	27
1986	19
1987	19
1988	44
1989	30
1990	15
1991	21
1992	10
1993	14
1994	12
1995	4
1996	21
1997	13
1998	17
1999	13
2000	13
2001	18
2002	30
2003	10
2004	6
2005	10
2006	19
2007	29

All-Time Record Progression

10 new records

10 all-time records were set at Heidelberg between 20 January 1978 and 20 January 1994. Each dot is a new record.

When Heidelberg set new all-time records
Date	Kind	Detail
1978-01-20	Record snow depth	Record snow depth 33.0 cm (13.0 in)
1978-12-08	Record daily precipitation	Record daily precipitation 127.5 mm (5.0 in)
1983-12-25	Record low maximum temperature	Record low maximum temperature -15.6 C (3.9 F)
1985-01-21	Record low maximum temperature	Record low maximum temperature -21.7 C (-7.1 F)
1985-02-02	Record daily snowfall	Record daily snowfall 25.4 cm (10.0 in)
1985-02-13	Record daily snowfall	Record daily snowfall 38.1 cm (15.0 in)
1985-02-13	Record snow depth	Record snow depth 48.3 cm (19.0 in)
1989-10-17	Record daily precipitation	Record daily precipitation 133.6 mm (5.3 in)
1994-01-19	Record low minimum temperature	Record low minimum temperature -32.2 C (-26.0 F)
1994-01-20	Record low minimum temperature	Record low minimum temperature -32.8 C (-27.0 F)

Wettest Day of Each Month

Oct: 133.6 mm (5.3 in)

The wettest day on record for each calendar month at Heidelberg. The most was 133.6 mm (5.3 in) on 17 October 1989.

Record daily precipitation for each month at Heidelberg
Month	Record daily precipitation (mm)	Date
Jan	70.6 mm (2.8 in)	23 January 2006
Feb	94.0 mm (3.7 in)	27 February 1962
Mar	67.1 mm (2.6 in)	23 March 1952
Apr	85.9 mm (3.4 in)	30 April 2005
May	101.6 mm (4.0 in)	31 May 2004
Jun	116.1 mm (4.6 in)	12 June 1960
Jul	105.4 mm (4.1 in)	23 July 1965
Aug	80.0 mm (3.1 in)	21 August 1961
Sep	90.9 mm (3.6 in)	14 September 1989
Oct	133.6 mm (5.3 in)	17 October 1989
Nov	91.4 mm (3.6 in)	9 November 1986
Dec	127.5 mm (5.0 in)	8 December 1978

Period of Record Coverage

1933 to 2007

74 years of record at Heidelberg, 1933 to 2007. 14 years have data for under 90 percent of days and are left out of rankings: 1933, 1977, 1978, 1979, 1980, 1982, 1996, 1997 and others.

Days with data per year at Heidelberg
Year	Days with data	Share of year	Complete
1933	164	45%	No
1934	351	96%	Yes
1935	352	96%	Yes
1936	359	98%	Yes
1937	362	99%	Yes
1938	362	99%	Yes
1939	365	100%	Yes
1940	358	98%	Yes
1941	365	100%	Yes
1942	365	100%	Yes
1943	363	99%	Yes
1944	366	100%	Yes
1945	365	100%	Yes
1946	364	100%	Yes
1947	358	98%	Yes
1948	360	98%	Yes
1949	356	98%	Yes
1950	364	100%	Yes
1951	365	100%	Yes
1952	365	100%	Yes
1953	365	100%	Yes
1954	364	100%	Yes
1955	361	99%	Yes
1956	366	100%	Yes
1957	364	100%	Yes
1958	365	100%	Yes
1959	361	99%	Yes
1960	365	100%	Yes
1961	364	100%	Yes
1962	365	100%	Yes
1963	363	99%	Yes
1964	335	92%	Yes
1965	364	100%	Yes
1966	365	100%	Yes
1967	364	100%	Yes
1968	357	98%	Yes
1969	364	100%	Yes
1970	364	100%	Yes
1971	365	100%	Yes
1972	366	100%	Yes
1973	365	100%	Yes
1974	364	100%	Yes
1975	365	100%	Yes
1976	360	98%	Yes
1977	220	60%	No
1978	187	51%	No
1979	192	53%	No
1980	157	43%	No
1982	274	75%	No
1983	364	100%	Yes
1984	366	100%	Yes
1985	349	96%	Yes
1986	364	100%	Yes
1987	364	100%	Yes
1988	366	100%	Yes
1989	365	100%	Yes
1990	362	99%	Yes
1991	365	100%	Yes
1992	363	99%	Yes
1993	365	100%	Yes
1994	360	99%	Yes
1995	365	100%	Yes
1996	181	49%	No
1997	279	76%	No
1998	339	93%	Yes
1999	355	97%	Yes
2000	268	73%	No
2001	230	63%	No
2002	315	86%	No
2003	334	92%	Yes
2004	204	56%	No
2005	296	81%	No
2006	355	97%	Yes
2007	294	81%	No

Latest Records

Latest records at Heidelberg
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
24 October 2007	Heidelberg, US	daily rain	67.3 mm (2.6 in)	37.3 mm (1.5 in)	48 years	55 of 100 (Notable)
9 October 2007	Heidelberg, US	daily high max	32.8 C (91.0 F)	0.6 C (1.1 F)	68 years	28 of 100 (Routine)
26 September 2007	Heidelberg, US	daily high max	33.3 C (91.9 F)	0.5 C (0.9 F)	73 years	30 of 100 (Routine)
25 September 2007	Heidelberg, US	daily high max	34.4 C (93.9 F)	1.1 C (2.0 F)	1 year	9 of 100 (Routine)
11 September 2007	Heidelberg, US	daily high min	20.6 C (69.1 F)	0.6 C (1.1 F)	73 years	30 of 100 (Routine)
10 September 2007	Heidelberg, US	daily high min (Tie)	20.0 C (68.0 F)	tie	60 years	6 of 100 (Routine)
29 August 2007	Heidelberg, US	daily high max (Tie)	36.7 C (98.1 F)	tie	53 years	5 of 100 (Routine)
25 August 2007	Heidelberg, US	daily high max	37.8 C (100.0 F)	1.7 C (3.1 F)	70 years	33 of 100 (Routine)
25 August 2007	Heidelberg, US	daily high min	22.2 C (72.0 F)	0.5 C (0.9 F)	30 years	17 of 100 (Routine)
24 August 2007	Heidelberg, US	daily high max	37.8 C (100.0 F)	1.1 C (2.0 F)	64 years	29 of 100 (Routine)
23 August 2007	Heidelberg, US	daily high max	36.7 C (98.1 F)	0.6 C (1.1 F)	24 years	16 of 100 (Routine)
17 August 2007	Heidelberg, US	daily high max	38.3 C (100.9 F)	0.5 C (0.9 F)	70 years	29 of 100 (Routine)
10 August 2007	Heidelberg, US	daily high max	36.1 C (97.0 F)	1.1 C (2.0 F)	26 years	18 of 100 (Routine)
9 August 2007	Heidelberg, US	daily high min	22.8 C (73.0 F)	1.7 C (3.1 F)	72 years	33 of 100 (Routine)
8 August 2007	Heidelberg, US	daily high min	22.2 C (72.0 F)	0.5 C (0.9 F)	0 years	8 of 100 (Routine)
7 August 2007	Heidelberg, US	daily high min (Tie)	21.7 C (71.1 F)	tie	68 years	6 of 100 (Routine)
29 July 2007	Heidelberg, US	daily low max	22.8 C (73.0 F)	2.2 C (4.0 F)	34 years	24 of 100 (Routine)
28 July 2007	Heidelberg, US	daily rain	49.8 mm (2.0 in)	6.9 mm (0.27 in)	58 years	29 of 100 (Routine)
25 July 2007	Heidelberg, US	daily low max	24.4 C (75.9 F)	2.8 C (5.0 F)	36 years	27 of 100 (Routine)
19 June 2007	Heidelberg, US	daily high max (Tie)	34.4 C (93.9 F)	tie	54 years	5 of 100 (Routine)

Climate Trend

58 complete years, 1934 to 2006

One stripe for each of 58 complete years at Heidelberg, 1934 to 2006. Blue stripes are years cooler than the station's own mean of 13.3 C (56.0 F); red stripes are warmer. The coolest year was 1989, at 12.1 C (53.7 F), and the warmest was 1938, at 14.5 C (58.2 F). The strongest colour marks a difference of 1.3 C (2.3 F).

Annual mean temperature at Heidelberg as warming stripes, 1934 to 2006
Year	Annual mean temperature	Difference from the station mean
1934	14.2 C	+0.87 C
1935	13.7 C	+0.34 C
1936	13.8 C	+0.52 C
1937	13.2 C	-0.13 C
1938	14.5 C	+1.21 C
1939	14.3 C	+0.98 C
1940	12.6 C	-0.69 C
1941	14.0 C	+0.70 C
1942	13.4 C	+0.11 C
1943	13.5 C	+0.16 C
1944	13.7 C	+0.42 C
1945	13.5 C	+0.22 C
1946	14.1 C	+0.82 C
1947	12.9 C	-0.42 C
1948	13.4 C	+0.07 C
1949	13.8 C	+0.43 C
1950	13.2 C	-0.09 C
1951	13.1 C	-0.18 C
1952	14.0 C	+0.66 C
1953	14.4 C	+1.08 C
1954	14.1 C	+0.73 C
1955	13.8 C	+0.50 C
1956	13.9 C	+0.58 C
1957	14.1 C	+0.76 C
1958	12.2 C	-1.10 C
1959	13.7 C	+0.42 C
1960	12.6 C	-0.74 C
1961	13.0 C	-0.37 C
1962	13.0 C	-0.29 C
1963	12.2 C	-1.15 C
1965	13.7 C	+0.40 C
1966	12.6 C	-0.70 C
1967	13.2 C	-0.15 C
1968	12.8 C	-0.51 C
1969	12.7 C	-0.64 C
1970	13.6 C	+0.23 C
1971	13.9 C	+0.61 C
1972	13.5 C	+0.21 C
1973	14.1 C	+0.78 C
1974	13.9 C	+0.55 C
1975	14.1 C	+0.74 C
1976	12.7 C	-0.67 C
1983	12.3 C	-1.02 C
1984	12.2 C	-1.15 C
1986	13.2 C	-0.11 C
1987	12.8 C	-0.52 C
1988	12.1 C	-1.20 C
1989	12.1 C	-1.26 C
1990	14.0 C	+0.70 C
1991	13.9 C	+0.62 C
1992	12.7 C	-0.59 C
1993	12.7 C	-0.62 C
1994	12.2 C	-1.09 C
1995	12.2 C	-1.12 C
1998	14.0 C	+0.71 C
1999	13.6 C	+0.27 C
2003	12.4 C	-0.90 C
2006	13.3 C	-0.07 C

The annual mean temperature here has fallen by 0.1 C (0.1 to 0.2) per decade over 1934 to 2006. In Fahrenheit: 0.3 F (0.1 to 0.4) per decade. The slope is a straight line fitted to 58 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at Heidelberg
Measure	Per decade (C)	Per decade (F)	Period	Complete years	Reading
Annual mean temperature	-0.1 C (-0.2 to -0.1) per decade	-0.3 F (-0.4 to -0.1) per decade	1934 to 2006	58	Fall
Mean daily maximum	-0.13 C (-0.23 to -0.04) per decade	-0.2 F (-0.4 to -0.1) per decade	1934 to 2006	58	Fall
Mean daily minimum	-0.15 C (-0.26 to -0.04) per decade	-0.3 F (-0.5 to -0.1) per decade	1934 to 2006	58	Fall

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

1932 to 2007

Yearly extremes at Heidelberg: 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)	1936	35.0 C (95.0 F)	74
Coldest night (TNn)	-32.8 C (-27.0 F)	1994	-18.9 C (-2.0 F)	75
Wettest day (Rx1day)	133.6 mm (5.3 in)	1989	62.0 mm (2.4 in)	76
Wettest five days (Rx5day)	190.7 mm (7.5 in)	1989	99.1 mm (3.9 in)	76
Longest dry spell (CDD)	29 days	1938	15 days	76

Hottest day (TXx)

The hottest day of the year at Heidelberg, 1932 to 2007. The record is 40.6 C (105.1 F) in 1936, marked on the chart; the median year is 35.0 C (95.0 F).

Hottest day (TXx) at Heidelberg by year
Year	Hottest day (TXx)
1932	n/a
1933	37.2 C (99.0 F)
1934	38.3 C (100.9 F)
1935	36.7 C (98.1 F)
1936	40.6 C (105.1 F)
1937	36.1 C (97.0 F)
1938	35.0 C (95.0 F)
1939	37.2 C (99.0 F)
1940	37.2 C (99.0 F)
1941	37.2 C (99.0 F)
1942	35.6 C (96.1 F)
1943	36.7 C (98.1 F)
1944	36.7 C (98.1 F)
1945	35.0 C (95.0 F)
1946	34.4 C (93.9 F)
1947	33.9 C (93.0 F)
1948	36.1 C (97.0 F)
1949	35.0 C (95.0 F)
1950	33.3 C (91.9 F)
1951	34.4 C (93.9 F)
1952	39.4 C (102.9 F)
1953	38.3 C (100.9 F)
1954	38.3 C (100.9 F)
1955	35.6 C (96.1 F)
1956	35.0 C (95.0 F)
1957	36.1 C (97.0 F)
1958	36.7 C (98.1 F)
1959	35.0 C (95.0 F)
1960	33.9 C (93.0 F)
1961	33.3 C (91.9 F)
1962	35.0 C (95.0 F)
1963	33.9 C (93.0 F)
1964	35.6 C (96.1 F)
1965	34.4 C (93.9 F)
1966	37.2 C (99.0 F)
1967	33.3 C (91.9 F)
1968	35.0 C (95.0 F)
1969	35.0 C (95.0 F)
1970	36.1 C (97.0 F)
1971	33.9 C (93.0 F)
1972	33.9 C (93.0 F)
1973	33.3 C (91.9 F)
1974	32.8 C (91.0 F)
1975	33.9 C (93.0 F)
1976	33.9 C (93.0 F)
1977	34.4 C (93.9 F)
1978	34.4 C (93.9 F)
1979	31.1 C (88.0 F)
1980	36.1 C (97.0 F)
1981	n/a
1982	35.0 C (95.0 F)
1983	37.2 C (99.0 F)
1984	35.0 C (95.0 F)
1985	33.9 C (93.0 F)
1986	36.7 C (98.1 F)
1987	36.7 C (98.1 F)
1988	40.6 C (105.1 F)
1989	35.0 C (95.0 F)
1990	36.7 C (98.1 F)
1991	35.6 C (96.1 F)
1992	33.3 C (91.9 F)
1993	35.6 C (96.1 F)
1994	34.4 C (93.9 F)
1995	36.1 C (97.0 F)
1996	32.8 C (91.0 F)
1997	35.0 C (95.0 F)
1998	35.6 C (96.1 F)
1999	38.3 C (100.9 F)
2000	32.8 C (91.0 F)
2001	33.3 C (91.9 F)
2002	35.6 C (96.1 F)
2003	32.8 C (91.0 F)
2004	32.2 C (90.0 F)
2005	35.0 C (95.0 F)
2006	35.6 C (96.1 F)
2007	38.3 C (100.9 F)

Coldest night (TNn)

The coldest night of the year at Heidelberg, 1932 to 2007. The record is -32.8 C (-27.0 F) in 1994, marked on the chart; the median year is -18.9 C (-2.0 F).

Coldest night (TNn) at Heidelberg by year
Year	Coldest night (TNn)
1932	n/a
1933	-14.4 C (6.1 F)
1934	-22.8 C (-9.0 F)
1935	-22.8 C (-9.0 F)
1936	-24.4 C (-11.9 F)
1937	-17.8 C (0.0 F)
1938	-17.8 C (0.0 F)
1939	-18.9 C (-2.0 F)
1940	-23.3 C (-9.9 F)
1941	-15.0 C (5.0 F)
1942	-24.4 C (-11.9 F)
1943	-20.0 C (-4.0 F)
1944	-17.2 C (1.0 F)
1945	-18.3 C (-0.9 F)
1946	-16.7 C (1.9 F)
1947	-18.3 C (-0.9 F)
1948	-25.6 C (-14.1 F)
1949	-12.2 C (10.0 F)
1950	-15.6 C (3.9 F)
1951	-22.2 C (-8.0 F)
1952	-13.9 C (7.0 F)
1953	-19.4 C (-2.9 F)
1954	-23.9 C (-11.0 F)
1955	-23.3 C (-9.9 F)
1956	-13.9 C (7.0 F)
1957	-21.7 C (-7.1 F)
1958	-19.4 C (-2.9 F)
1959	-20.0 C (-4.0 F)
1960	-22.8 C (-9.0 F)
1961	-25.6 C (-14.1 F)
1962	-26.1 C (-15.0 F)
1963	-30.0 C (-22.0 F)
1964	-16.1 C (3.0 F)
1965	-23.3 C (-9.9 F)
1966	-26.7 C (-16.1 F)
1967	-19.4 C (-2.9 F)
1968	-20.0 C (-4.0 F)
1969	-22.2 C (-8.0 F)
1970	-24.4 C (-11.9 F)
1971	-22.8 C (-9.0 F)
1972	-22.2 C (-8.0 F)
1973	-17.2 C (1.0 F)
1974	-13.3 C (8.1 F)
1975	-15.6 C (3.9 F)
1976	-18.3 C (-0.9 F)
1977	-26.7 C (-16.1 F)
1978	-23.3 C (-9.9 F)
1979	-18.3 C (-0.9 F)
1980	-17.8 C (0.0 F)
1981	-22.2 C (-8.0 F)
1982	-13.3 C (8.1 F)
1983	-22.2 C (-8.0 F)
1984	-27.2 C (-17.0 F)
1985	-30.0 C (-22.0 F)
1986	-17.8 C (0.0 F)
1987	-22.8 C (-9.0 F)
1988	-18.3 C (-0.9 F)
1989	-25.0 C (-13.0 F)
1990	-11.1 C (12.0 F)
1991	-16.1 C (3.0 F)
1992	-15.6 C (3.9 F)
1993	-18.9 C (-2.0 F)
1994	-32.8 C (-27.0 F)
1995	-19.4 C (-2.9 F)
1996	-27.8 C (-18.0 F)
1997	-8.9 C (16.0 F)
1998	-12.8 C (9.0 F)
1999	-16.1 C (3.0 F)
2000	-15.6 C (3.9 F)
2001	-7.2 C (19.0 F)
2002	-12.2 C (10.0 F)
2003	-17.2 C (1.0 F)
2004	-18.9 C (-2.0 F)
2005	-16.1 C (3.0 F)
2006	-14.4 C (6.1 F)
2007	-16.7 C (1.9 F)

Wettest day (Rx1day)

The wettest day of the year at Heidelberg, 1932 to 2007. The record is 133.6 mm (5.3 in) in 1989, marked on the chart; the median year is 62.0 mm (2.4 in).

Wettest day (Rx1day) at Heidelberg by year
Year	Wettest day (Rx1day)
1932	90.7 mm (3.6 in)
1933	49.3 mm (1.9 in)
1934	69.1 mm (2.7 in)
1935	63.0 mm (2.5 in)
1936	78.0 mm (3.1 in)
1937	50.8 mm (2.0 in)
1938	78.2 mm (3.1 in)
1939	82.3 mm (3.2 in)
1940	46.2 mm (1.8 in)
1941	48.8 mm (1.9 in)
1942	57.9 mm (2.3 in)
1943	68.6 mm (2.7 in)
1944	39.1 mm (1.5 in)
1945	66.0 mm (2.6 in)
1946	63.8 mm (2.5 in)
1947	53.1 mm (2.1 in)
1948	67.3 mm (2.6 in)
1949	47.0 mm (1.9 in)
1950	50.8 mm (2.0 in)
1951	56.4 mm (2.2 in)
1952	79.2 mm (3.1 in)
1953	37.6 mm (1.5 in)
1954	62.2 mm (2.4 in)
1955	87.6 mm (3.4 in)
1956	54.1 mm (2.1 in)
1957	79.2 mm (3.1 in)
1958	54.9 mm (2.2 in)
1959	65.5 mm (2.6 in)
1960	116.1 mm (4.6 in)
1961	80.0 mm (3.1 in)
1962	94.0 mm (3.7 in)
1963	61.7 mm (2.4 in)
1964	52.1 mm (2.1 in)
1965	105.4 mm (4.1 in)
1966	52.1 mm (2.1 in)
1967	58.4 mm (2.3 in)
1968	57.4 mm (2.3 in)
1969	54.1 mm (2.1 in)
1970	56.1 mm (2.2 in)
1971	58.9 mm (2.3 in)
1972	77.2 mm (3.0 in)
1973	71.6 mm (2.8 in)
1974	70.1 mm (2.8 in)
1975	72.9 mm (2.9 in)
1976	57.4 mm (2.3 in)
1977	50.3 mm (2.0 in)
1978	127.5 mm (5.0 in)
1979	64.5 mm (2.5 in)
1980	64.5 mm (2.5 in)
1981	57.7 mm (2.3 in)
1982	59.9 mm (2.4 in)
1983	49.0 mm (1.9 in)
1984	86.4 mm (3.4 in)
1985	41.9 mm (1.6 in)
1986	91.4 mm (3.6 in)
1987	56.4 mm (2.2 in)
1988	61.2 mm (2.4 in)
1989	133.6 mm (5.3 in)
1990	71.6 mm (2.8 in)
1991	64.5 mm (2.5 in)
1992	59.2 mm (2.3 in)
1993	66.8 mm (2.6 in)
1994	47.5 mm (1.9 in)
1995	50.8 mm (2.0 in)
1996	49.5 mm (1.9 in)
1997	74.7 mm (2.9 in)
1998	50.3 mm (2.0 in)
1999	53.1 mm (2.1 in)
2000	51.8 mm (2.0 in)
2001	40.4 mm (1.6 in)
2002	74.7 mm (2.9 in)
2003	59.7 mm (2.4 in)
2004	101.6 mm (4.0 in)
2005	85.9 mm (3.4 in)
2006	70.6 mm (2.8 in)
2007	67.3 mm (2.6 in)

Wettest five days (Rx5day)

The wettest five days of the year at Heidelberg, 1932 to 2007. The record is 190.7 mm (7.5 in) in 1989, marked on the chart; the median year is 99.1 mm (3.9 in).

Wettest five days (Rx5day) at Heidelberg by year
Year	Wettest five days (Rx5day)
1932	129.2 mm (5.1 in)
1933	89.7 mm (3.5 in)
1934	78.8 mm (3.1 in)
1935	106.9 mm (4.2 in)
1936	103.4 mm (4.1 in)
1937	121.2 mm (4.8 in)
1938	127.2 mm (5.0 in)
1939	131.1 mm (5.2 in)
1940	70.6 mm (2.8 in)
1941	107.3 mm (4.2 in)
1942	132.3 mm (5.2 in)
1943	89.0 mm (3.5 in)
1944	84.1 mm (3.3 in)
1945	96.5 mm (3.8 in)
1946	99.8 mm (3.9 in)
1947	77.0 mm (3.0 in)
1948	96.5 mm (3.8 in)
1949	87.4 mm (3.4 in)
1950	102.1 mm (4.0 in)
1951	111.3 mm (4.4 in)
1952	126.1 mm (5.0 in)
1953	83.9 mm (3.3 in)
1954	74.7 mm (2.9 in)
1955	110.6 mm (4.4 in)
1956	111.6 mm (4.4 in)
1957	139.2 mm (5.5 in)
1958	97.8 mm (3.9 in)
1959	75.6 mm (3.0 in)
1960	131.6 mm (5.2 in)
1961	88.7 mm (3.5 in)
1962	178.6 mm (7.0 in)
1963	82.5 mm (3.2 in)
1964	102.9 mm (4.1 in)
1965	116.8 mm (4.6 in)
1966	84.6 mm (3.3 in)
1967	89.9 mm (3.5 in)
1968	117.2 mm (4.6 in)
1969	91.9 mm (3.6 in)
1970	139.4 mm (5.5 in)
1971	81.5 mm (3.2 in)
1972	171.5 mm (6.8 in)
1973	161.2 mm (6.3 in)
1974	141.5 mm (5.6 in)
1975	118.1 mm (4.6 in)
1976	83.8 mm (3.3 in)
1977	70.6 mm (2.8 in)
1978	98.3 mm (3.9 in)
1979	96.8 mm (3.8 in)
1980	71.9 mm (2.8 in)
1981	64.9 mm (2.6 in)
1982	60.2 mm (2.4 in)
1983	65.4 mm (2.6 in)
1984	152.2 mm (6.0 in)
1985	85.9 mm (3.4 in)
1986	148.6 mm (5.9 in)
1987	97.5 mm (3.8 in)
1988	92.0 mm (3.6 in)
1989	190.7 mm (7.5 in)
1990	158.4 mm (6.2 in)
1991	127.9 mm (5.0 in)
1992	87.6 mm (3.4 in)
1993	104.4 mm (4.1 in)
1994	96.7 mm (3.8 in)
1995	76.2 mm (3.0 in)
1996	116.0 mm (4.6 in)
1997	122.1 mm (4.8 in)
1998	127.1 mm (5.0 in)
1999	74.2 mm (2.9 in)
2000	102.1 mm (4.0 in)
2001	69.6 mm (2.7 in)
2002	93.8 mm (3.7 in)
2003	130.7 mm (5.1 in)
2004	172.5 mm (6.8 in)
2005	115.4 mm (4.5 in)
2006	79.0 mm (3.1 in)
2007	81.3 mm (3.2 in)

Longest dry spell (CDD)

The longest dry spell of the year at Heidelberg, 1932 to 2007. The record is 29 days in 1938, marked on the chart; the median year is 15 days.

Longest dry spell (CDD) at Heidelberg by year
Year	Longest dry spell (CDD)
1932	17 days
1933	12 days
1934	18 days
1935	13 days
1936	18 days
1937	10 days
1938	29 days
1939	15 days
1940	21 days
1941	17 days
1942	14 days
1943	19 days
1944	15 days
1945	13 days
1946	22 days
1947	15 days
1948	13 days
1949	17 days
1950	16 days
1951	13 days
1952	23 days
1953	22 days
1954	16 days
1955	21 days
1956	14 days
1957	25 days
1958	13 days
1959	18 days
1960	13 days
1961	12 days
1962	13 days
1963	19 days
1964	20 days
1965	27 days
1966	14 days
1967	24 days
1968	18 days
1969	12 days
1970	12 days
1971	14 days
1972	13 days
1973	18 days
1974	13 days
1975	10 days
1976	14 days
1977	21 days
1978	11 days
1979	14 days
1980	17 days
1981	13 days
1982	14 days
1983	14 days
1984	18 days
1985	12 days
1986	15 days
1987	12 days
1988	14 days
1989	14 days
1990	13 days
1991	23 days
1992	14 days
1993	17 days
1994	13 days
1995	13 days
1996	14 days
1997	15 days
1998	20 days
1999	21 days
2000	14 days
2001	16 days
2002	19 days
2003	13 days
2004	16 days
2005	16 days
2006	11 days
2007	16 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

58 years with a frost

Across 58 years with a frost, the median last spring frost at Heidelberg falls on 26 April and the median first autumn frost on 16 October, which leaves a median of 171 days between them.

Fitted over all years, the growing season changes by +1.1 days per decade at this station.

Frost dates and growing season at Heidelberg
Measure	Median, all years	Earliest period	Recent period (1962 to 2006)	Recent against earliest	Fitted trend
Last spring frost	26 April	n/a	27 April	n/a	-0.9 days per decade
First autumn frost	16 October	n/a	17 October	n/a	+0.2 days per decade
Growing days	171 days	n/a	173 days	n/a	+1.1 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

66 years, 1932 to 2006

A day with at least 62.4 mm (2.5 in) of rain is expected about once in 2 years. A day with at least 135.7 mm (5.3 in) of rain is expected about once in 100 years.

Rainfall return levels at Heidelberg: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	62.4 mm (2.5 in)
5 years	78.7 mm (3.1 in)
10 years	90.7 mm (3.6 in)
25 years	107.4 mm (4.2 in)
50 years	121.0 mm (4.8 in)
100 years	135.7 mm (5.3 in)	Longer than the 66 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, 66 years of values from 1932 to 2006.

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: 133.6 mm (5.3 in) in 1989; 127.5 mm (5.0 in) in 1978; 116.1 mm (4.6 in) in 1960.

Station Changes

No change in the annual mean temperature of this station was found against its neighbours.

Download the Data

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