Derby Post Office Weather Records (ASN00003007)

Record envelope, standing records and threshold days for Derby Post Office (ASN00003007), Australia, with 114 years of record.

Key Facts for Derby Post Office

Derby Post Office (ASN00003007) is a weather station in Australia at -17.30 latitude and 123.63 longitude, 8 m (26 ft) above sea level.
The station reports from 1884 to 1997, 114 years of record.
1,464 records set at Derby Post Office still stand.
Records are tracked for prcp: an element needs 30 years of data to be eligible.
Derby Post Office set a daily record precipitation of 9.8 mm (0.39 in) on 13 May 1997.

About the Station

Location: Australia, -17.30 latitude, 123.63 longitude.
Elevation: 8 m (26 ft).
Period of record: 1884 to 1997, 114 years.
Eligible elements: 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 Derby Post Office. 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 Derby Post Office, with 2026 drawn through them
Month	Highest record high	Lowest record low	2026 highest maximum	2026 lowest minimum
Jan	45.2 C (113.4 F)	17.1 C (62.8 F)	n/a	n/a
Feb	43.8 C (110.8 F)	19.4 C (66.9 F)	n/a	n/a
Mar	42.8 C (109.0 F)	18.8 C (65.8 F)	n/a	n/a
Apr	42.1 C (107.8 F)	13.9 C (57.0 F)	n/a	n/a
May	39.4 C (102.9 F)	9.6 C (49.3 F)	n/a	n/a
Jun	36.2 C (97.2 F)	5.8 C (42.4 F)	n/a	n/a
Jul	36.7 C (98.1 F)	5.0 C (41.0 F)	n/a	n/a
Aug	39.5 C (103.1 F)	8.0 C (46.4 F)	n/a	n/a
Sep	42.8 C (109.0 F)	12.4 C (54.3 F)	n/a	n/a
Oct	43.4 C (110.1 F)	14.0 C (57.2 F)	n/a	n/a
Nov	47.8 C (118.0 F)	18.8 C (65.8 F)	n/a	n/a
Dec	45.7 C (114.3 F)	20.3 C (68.5 F)	n/a	n/a

Which Years Hold Standing Records

1,464 standing records

1,464 records at Derby Post Office still stand. 1988 holds the most, with 103.

Standing records at Derby Post Office by the year they were set
Year set	Standing records
1964	67
1965	56
1966	70
1967	60
1968	70
1969	50
1970	76
1971	59
1972	12
1981	5
1982	68
1983	55
1984	66
1985	51
1986	69
1987	55
1988	103
1989	73
1990	79
1991	43
1992	75
1993	55
1994	41
1995	45
1996	50
1997	11

Wettest Day of Each Month

Jan: 418.3 mm (16.5 in)

The wettest day on record for each calendar month at Derby Post Office. The most was 418.3 mm (16.5 in) on 7 January 1917.

Record daily precipitation for each month at Derby Post Office
Month	Record daily precipitation (mm)	Date
Jan	418.3 mm (16.5 in)	7 January 1917
Feb	251.7 mm (9.9 in)	3 February 1932
Mar	206.5 mm (8.1 in)	3 March 1916
Apr	191.5 mm (7.5 in)	24 April 1926
May	188.0 mm (7.4 in)	25 May 1949
Jun	76.5 mm (3.0 in)	17 June 1915
Jul	88.1 mm (3.5 in)	15 July 1956
Aug	20.3 mm (0.8 in)	11 August 1933
Sep	10.4 mm (0.4 in)	8 September 1968
Oct	32.0 mm (1.3 in)	27 October 1950
Nov	70.1 mm (2.8 in)	9 November 1916
Dec	139.7 mm (5.5 in)	20 December 1926

Period of Record Coverage

1964 to 1997

26 years of record at Derby Post Office, 1964 to 1997. 4 years have data for under 90 percent of days and are left out of rankings: 1972, 1981, 1995, 1997.

Days with data per year at Derby Post Office
Year	Days with data	Share of year	Complete
1964	366	100%	Yes
1965	365	100%	Yes
1966	365	100%	Yes
1967	362	99%	Yes
1968	365	100%	Yes
1969	347	95%	Yes
1970	356	98%	Yes
1971	353	97%	Yes
1972	179	49%	No
1981	31	8%	No
1982	362	99%	Yes
1983	364	100%	Yes
1984	359	98%	Yes
1985	365	100%	Yes
1986	361	99%	Yes
1987	357	98%	Yes
1988	346	95%	Yes
1989	362	99%	Yes
1990	361	99%	Yes
1991	351	96%	Yes
1992	361	99%	Yes
1993	360	99%	Yes
1994	346	95%	Yes
1995	320	88%	No
1996	336	92%	Yes
1997	162	44%	No

Latest Records

Latest records at Derby Post Office
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
13 May 1997	Derby Post Office, AU	daily rain	9.8 mm (0.39 in)	2.9 mm (0.11 in)	34 years	20 of 100 (Routine)
11 May 1997	Derby Post Office, AU	daily rain	42.8 mm (1.7 in)	16.9 mm (0.7 in)	82 years	40 of 100 (Notable)
10 May 1997	Derby Post Office, AU	daily rain	66.6 mm (2.6 in)	44.2 mm (1.7 in)	34 years	37 of 100 (Notable)
30 January 1997	Derby Post Office, AU	daily rain	128.4 mm (5.1 in)	54.7 mm (2.2 in)	37 years	41 of 100 (Notable)
26 January 1997	Derby Post Office, AU	daily rain	45.6 mm (1.8 in)	16.1 mm (0.6 in)	76 years	38 of 100 (Notable)
30 December 1996	Derby Post Office, AU	daily rain	34.8 mm (1.4 in)	17.0 mm (0.7 in)	1 year	20 of 100 (Routine)
15 December 1996	Derby Post Office, AU	daily rain	80.0 mm (3.1 in)	24.6 mm (1.0 in)	82 years	49 of 100 (Notable)
22 November 1996	Derby Post Office, AU	daily rain	24.8 mm (1.0 in)	10.3 mm (0.4 in)	76 years	20 of 100 (Routine)
6 November 1996	Derby Post Office, AU	daily rain	5.0 mm (0.20 in)	1.7 mm (0.07 in)	70 years	20 of 100 (Routine)
8 June 1996	Derby Post Office, AU	daily rain	10.1 mm (0.4 in)	3.7 mm (0.15 in)	34 years	20 of 100 (Routine)
12 April 1996	Derby Post Office, AU	daily rain	17.0 mm (0.7 in)	3.0 mm (0.12 in)	39 years	20 of 100 (Routine)
11 March 1996	Derby Post Office, AU	daily rain	62.6 mm (2.5 in)	10.5 mm (0.4 in)	71 years	35 of 100 (Notable)
8 March 1996	Derby Post Office, AU	daily rain	92.0 mm (3.6 in)	6.4 mm (0.25 in)	52 years	27 of 100 (Routine)
8 February 1996	Derby Post Office, AU	daily rain	53.4 mm (2.1 in)	21.1 mm (0.8 in)	77 years	43 of 100 (Notable)
30 December 1995	Derby Post Office, AU	daily rain	17.8 mm (0.7 in)	0.5 mm (0.02 in)	60 years	20 of 100 (Routine)
19 February 1994	Derby Post Office, AU	daily rain	66.0 mm (2.6 in)	17.7 mm (0.7 in)	46 years	31 of 100 (Routine)
17 December 1993	Derby Post Office, AU	daily rain	63.3 mm (2.5 in)	37.3 mm (1.5 in)	2 years	33 of 100 (Routine)
28 November 1993	Derby Post Office, AU	daily rain	15.0 mm (0.6 in)	3.1 mm (0.12 in)	36 years	20 of 100 (Routine)
14 June 1993	Derby Post Office, AU	daily rain	31.0 mm (1.2 in)	24.9 mm (1.0 in)	82 years	53 of 100 (Notable)
1 February 1993	Derby Post Office, AU	daily rain	71.8 mm (2.8 in)	44.9 mm (1.8 in)	51 years	46 of 100 (Notable)

Climate Trend

20 complete years, 1964 to 1994

One stripe for each of 20 complete years at Derby Post Office, 1964 to 1994. Blue stripes are years cooler than the station's own mean of 28.1 C (82.5 F); red stripes are warmer. The coolest year was 1984, at 27.2 C (81.0 F), and the warmest was 1992, at 29.4 C (84.8 F). The strongest colour marks a difference of 1.3 C (2.3 F).

Annual mean temperature at Derby Post Office as warming stripes, 1964 to 1994
Year	Annual mean temperature	Difference from the station mean
1964	27.8 C	-0.25 C
1965	27.8 C	-0.21 C
1966	27.8 C	-0.24 C
1967	27.4 C	-0.62 C
1968	28.0 C	-0.07 C
1970	28.2 C	+0.15 C
1971	27.4 C	-0.61 C
1982	27.3 C	-0.79 C
1983	27.6 C	-0.44 C
1984	27.2 C	-0.82 C
1985	27.7 C	-0.39 C
1986	28.1 C	+0.02 C
1987	27.9 C	-0.15 C
1988	29.1 C	+1.03 C
1989	28.6 C	+0.56 C
1990	28.9 C	+0.86 C
1991	28.3 C	+0.24 C
1992	29.4 C	+1.30 C
1993	28.6 C	+0.56 C
1994	27.9 C	-0.12 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

1884 to 1997

Yearly extremes at Derby Post Office: the record and the median year
Measure	Record	Year of the record	Median year	Years with a value
Hottest day (TXx)	47.8 C (118.0 F)	1968	43.3 C (110.0 F)	26
Coldest night (TNn)	5.0 C (41.0 F)	1965	9.4 C (48.9 F)	26
Wettest day (Rx1day)	418.3 mm (16.5 in)	1917	68.3 mm (2.7 in)	107
Wettest five days (Rx5day)	675.1 mm (26.6 in)	1917	116.3 mm (4.6 in)	107
Longest dry spell (CDD)	302 days	1924	143 days	107

Hottest day (TXx)

The hottest day of the year at Derby Post Office, 1884 to 1997. The record is 47.8 C (118.0 F) in 1968, marked on the chart; the median year is 43.3 C (110.0 F).

Hottest day (TXx) at Derby Post Office by year
Year	Hottest day (TXx)
1884	n/a
1885	n/a
1886	n/a
1887	n/a
1888	n/a
1889	n/a
1890	n/a
1891	n/a
1892	n/a
1893	n/a
1894	n/a
1895	n/a
1896	n/a
1897	n/a
1898	n/a
1899	n/a
1900	n/a
1901	n/a
1902	n/a
1903	n/a
1904	n/a
1905	n/a
1906	n/a
1907	n/a
1908	n/a
1909	n/a
1910	n/a
1911	n/a
1912	n/a
1913	n/a
1914	n/a
1915	n/a
1916	n/a
1917	n/a
1918	n/a
1919	n/a
1920	n/a
1921	n/a
1922	n/a
1923	n/a
1924	n/a
1925	n/a
1926	n/a
1927	n/a
1928	n/a
1929	n/a
1930	n/a
1931	n/a
1932	n/a
1933	n/a
1934	n/a
1935	n/a
1936	n/a
1937	n/a
1938	n/a
1939	n/a
1940	n/a
1941	n/a
1942	n/a
1943	n/a
1944	n/a
1945	n/a
1946	n/a
1947	n/a
1948	n/a
1949	n/a
1950	n/a
1951	n/a
1952	n/a
1953	n/a
1954	n/a
1955	n/a
1956	n/a
1957	n/a
1958	n/a
1959	n/a
1960	n/a
1961	n/a
1962	n/a
1963	n/a
1964	42.9 C (109.2 F)
1965	44.4 C (111.9 F)
1966	41.7 C (107.1 F)
1967	45.6 C (114.1 F)
1968	47.8 C (118.0 F)
1969	43.3 C (109.9 F)
1970	43.7 C (110.7 F)
1971	43.3 C (109.9 F)
1972	42.4 C (108.3 F)
1980	n/a
1981	42.6 C (108.7 F)
1982	43.2 C (109.8 F)
1983	41.4 C (106.5 F)
1984	43.9 C (111.0 F)
1985	45.2 C (113.4 F)
1986	45.7 C (114.3 F)
1987	42.6 C (108.7 F)
1988	46.5 C (115.7 F)
1989	43.6 C (110.5 F)
1990	44.4 C (111.9 F)
1991	42.1 C (107.8 F)
1992	43.0 C (109.4 F)
1993	43.4 C (110.1 F)
1994	44.0 C (111.2 F)
1995	41.7 C (107.1 F)
1996	43.8 C (110.8 F)
1997	39.7 C (103.5 F)

Coldest night (TNn)

The coldest night of the year at Derby Post Office, 1884 to 1997. The record is 5.0 C (41.0 F) in 1965, marked on the chart; the median year is 9.4 C (48.9 F).

Coldest night (TNn) at Derby Post Office by year
Year	Coldest night (TNn)
1884	n/a
1885	n/a
1886	n/a
1887	n/a
1888	n/a
1889	n/a
1890	n/a
1891	n/a
1892	n/a
1893	n/a
1894	n/a
1895	n/a
1896	n/a
1897	n/a
1898	n/a
1899	n/a
1900	n/a
1901	n/a
1902	n/a
1903	n/a
1904	n/a
1905	n/a
1906	n/a
1907	n/a
1908	n/a
1909	n/a
1910	n/a
1911	n/a
1912	n/a
1913	n/a
1914	n/a
1915	n/a
1916	n/a
1917	n/a
1918	n/a
1919	n/a
1920	n/a
1921	n/a
1922	n/a
1923	n/a
1924	n/a
1925	n/a
1926	n/a
1927	n/a
1928	n/a
1929	n/a
1930	n/a
1931	n/a
1932	n/a
1933	n/a
1934	n/a
1935	n/a
1936	n/a
1937	n/a
1938	n/a
1939	n/a
1940	n/a
1941	n/a
1942	n/a
1943	n/a
1944	n/a
1945	n/a
1946	n/a
1947	n/a
1948	n/a
1949	n/a
1950	n/a
1951	n/a
1952	n/a
1953	n/a
1954	n/a
1955	n/a
1956	n/a
1957	n/a
1958	n/a
1959	n/a
1960	n/a
1961	n/a
1962	n/a
1963	n/a
1964	7.1 C (44.8 F)
1965	5.0 C (41.0 F)
1966	9.6 C (49.3 F)
1967	7.1 C (44.8 F)
1968	9.2 C (48.6 F)
1969	10.2 C (50.4 F)
1970	10.6 C (51.1 F)
1971	5.7 C (42.3 F)
1972	11.1 C (52.0 F)
1980	n/a
1981	22.3 C (72.1 F)
1982	8.3 C (46.9 F)
1983	8.1 C (46.6 F)
1984	7.8 C (46.0 F)
1985	8.4 C (47.1 F)
1986	8.0 C (46.4 F)
1987	9.8 C (49.6 F)
1988	8.3 C (46.9 F)
1989	7.2 C (45.0 F)
1990	9.9 C (49.8 F)
1991	10.7 C (51.3 F)
1992	11.0 C (51.8 F)
1993	9.7 C (49.5 F)
1994	9.0 C (48.2 F)
1995	10.4 C (50.7 F)
1996	9.8 C (49.6 F)
1997	10.4 C (50.7 F)

Wettest day (Rx1day)

The wettest day of the year at Derby Post Office, 1884 to 1997. The record is 418.3 mm (16.5 in) in 1917, marked on the chart; the median year is 68.3 mm (2.7 in).

Wettest day (Rx1day) at Derby Post Office by year
Year	Wettest day (Rx1day)
1884	0.0 mm (0.00 in)
1885	0.0 mm (0.00 in)
1886	0.0 mm (0.00 in)
1887	0.0 mm (0.00 in)
1888	0.0 mm (0.00 in)
1889	0.0 mm (0.00 in)
1890	0.0 mm (0.00 in)
1891	0.0 mm (0.00 in)
1892	0.0 mm (0.00 in)
1893	0.0 mm (0.00 in)
1894	0.0 mm (0.00 in)
1895	0.0 mm (0.00 in)
1896	0.0 mm (0.00 in)
1897	0.0 mm (0.00 in)
1898	0.0 mm (0.00 in)
1899	0.0 mm (0.00 in)
1900	0.0 mm (0.00 in)
1901	0.0 mm (0.00 in)
1902	0.0 mm (0.00 in)
1903	0.0 mm (0.00 in)
1904	0.0 mm (0.00 in)
1905	0.0 mm (0.00 in)
1906	0.0 mm (0.00 in)
1907	74.2 mm (2.9 in)
1908	78.2 mm (3.1 in)
1909	86.4 mm (3.4 in)
1910	71.4 mm (2.8 in)
1911	79.5 mm (3.1 in)
1912	109.5 mm (4.3 in)
1913	52.8 mm (2.1 in)
1914	83.6 mm (3.3 in)
1915	95.0 mm (3.7 in)
1916	206.5 mm (8.1 in)
1917	418.3 mm (16.5 in)
1918	60.5 mm (2.4 in)
1919	72.4 mm (2.9 in)
1920	106.9 mm (4.2 in)
1921	49.5 mm (1.9 in)
1922	136.1 mm (5.4 in)
1923	100.6 mm (4.0 in)
1924	16.3 mm (0.6 in)
1925	52.1 mm (2.1 in)
1926	191.5 mm (7.5 in)
1927	68.3 mm (2.7 in)
1928	39.1 mm (1.5 in)
1929	57.9 mm (2.3 in)
1930	92.7 mm (3.6 in)
1931	311.2 mm (12.3 in)
1932	251.7 mm (9.9 in)
1933	66.0 mm (2.6 in)
1934	81.3 mm (3.2 in)
1935	89.9 mm (3.5 in)
1936	54.4 mm (2.1 in)
1937	61.5 mm (2.4 in)
1938	61.5 mm (2.4 in)
1939	114.3 mm (4.5 in)
1940	96.0 mm (3.8 in)
1941	59.4 mm (2.3 in)
1942	79.2 mm (3.1 in)
1943	136.4 mm (5.4 in)
1944	85.6 mm (3.4 in)
1945	82.0 mm (3.2 in)
1946	192.3 mm (7.6 in)
1947	197.1 mm (7.8 in)
1948	68.1 mm (2.7 in)
1949	188.0 mm (7.4 in)
1950	66.0 mm (2.6 in)
1951	43.2 mm (1.7 in)
1952	24.9 mm (1.0 in)
1953	83.1 mm (3.3 in)
1954	72.4 mm (2.9 in)
1955	64.8 mm (2.6 in)
1956	99.1 mm (3.9 in)
1957	80.5 mm (3.2 in)
1958	36.6 mm (1.4 in)
1959	20.8 mm (0.8 in)
1960	141.2 mm (5.6 in)
1961	113.8 mm (4.5 in)
1962	99.6 mm (3.9 in)
1963	68.3 mm (2.7 in)
1964	141.2 mm (5.6 in)
1965	66.5 mm (2.6 in)
1966	145.5 mm (5.7 in)
1967	0.0 mm (0.00 in)
1968	82.3 mm (3.2 in)
1969	129.5 mm (5.1 in)
1970	47.8 mm (1.9 in)
1971	75.7 mm (3.0 in)
1972	49.5 mm (1.9 in)
1980	19.6 mm (0.8 in)
1981	52.0 mm (2.0 in)
1982	124.9 mm (4.9 in)
1983	103.4 mm (4.1 in)
1984	120.2 mm (4.7 in)
1985	61.6 mm (2.4 in)
1986	116.3 mm (4.6 in)
1987	73.6 mm (2.9 in)
1988	68.8 mm (2.7 in)
1989	69.0 mm (2.7 in)
1990	36.2 mm (1.4 in)
1991	103.0 mm (4.1 in)
1992	31.6 mm (1.2 in)
1993	71.8 mm (2.8 in)
1994	66.0 mm (2.6 in)
1995	75.6 mm (3.0 in)
1996	92.0 mm (3.6 in)
1997	128.4 mm (5.1 in)

Wettest five days (Rx5day)

The wettest five days of the year at Derby Post Office, 1884 to 1997. The record is 675.1 mm (26.6 in) in 1917, marked on the chart; the median year is 116.3 mm (4.6 in).

Wettest five days (Rx5day) at Derby Post Office by year
Year	Wettest five days (Rx5day)
1884	0.0 mm (0.00 in)
1885	0.0 mm (0.00 in)
1886	0.0 mm (0.00 in)
1887	0.0 mm (0.00 in)
1888	0.0 mm (0.00 in)
1889	0.0 mm (0.00 in)
1890	0.0 mm (0.00 in)
1891	0.0 mm (0.00 in)
1892	0.0 mm (0.00 in)
1893	0.0 mm (0.00 in)
1894	0.0 mm (0.00 in)
1895	0.0 mm (0.00 in)
1896	0.0 mm (0.00 in)
1897	0.0 mm (0.00 in)
1898	0.0 mm (0.00 in)
1899	0.0 mm (0.00 in)
1900	0.0 mm (0.00 in)
1901	0.0 mm (0.00 in)
1902	0.0 mm (0.00 in)
1903	0.0 mm (0.00 in)
1904	0.0 mm (0.00 in)
1905	0.0 mm (0.00 in)
1906	0.0 mm (0.00 in)
1907	122.4 mm (4.8 in)
1908	261.5 mm (10.3 in)
1909	93.8 mm (3.7 in)
1910	164.9 mm (6.5 in)
1911	80.0 mm (3.1 in)
1912	256.8 mm (10.1 in)
1913	81.8 mm (3.2 in)
1914	204.1 mm (8.0 in)
1915	205.3 mm (8.1 in)
1916	379.8 mm (15.0 in)
1917	675.1 mm (26.6 in)
1918	145.1 mm (5.7 in)
1919	127.0 mm (5.0 in)
1920	248.2 mm (9.8 in)
1921	85.3 mm (3.4 in)
1922	276.1 mm (10.9 in)
1923	141.0 mm (5.6 in)
1924	28.7 mm (1.1 in)
1925	87.4 mm (3.4 in)
1926	304.0 mm (12.0 in)
1927	116.3 mm (4.6 in)
1928	70.3 mm (2.8 in)
1929	108.7 mm (4.3 in)
1930	327.1 mm (12.9 in)
1931	443.7 mm (17.5 in)
1932	378.3 mm (14.9 in)
1933	96.3 mm (3.8 in)
1934	105.3 mm (4.1 in)
1935	186.6 mm (7.3 in)
1936	134.2 mm (5.3 in)
1937	162.9 mm (6.4 in)
1938	98.8 mm (3.9 in)
1939	170.5 mm (6.7 in)
1940	125.2 mm (4.9 in)
1941	106.5 mm (4.2 in)
1942	175.8 mm (6.9 in)
1943	235.5 mm (9.3 in)
1944	184.5 mm (7.3 in)
1945	110.6 mm (4.4 in)
1946	239.3 mm (9.4 in)
1947	238.3 mm (9.4 in)
1948	137.3 mm (5.4 in)
1949	339.9 mm (13.4 in)
1950	164.6 mm (6.5 in)
1951	107.0 mm (4.2 in)
1952	65.1 mm (2.6 in)
1953	119.2 mm (4.7 in)
1954	231.2 mm (9.1 in)
1955	94.7 mm (3.7 in)
1956	156.7 mm (6.2 in)
1957	139.2 mm (5.5 in)
1958	73.2 mm (2.9 in)
1959	40.9 mm (1.6 in)
1960	343.4 mm (13.5 in)
1961	167.0 mm (6.6 in)
1962	172.8 mm (6.8 in)
1963	110.7 mm (4.4 in)
1964	266.2 mm (10.5 in)
1965	79.9 mm (3.1 in)
1966	254.2 mm (10.0 in)
1967	0.0 mm (0.00 in)
1968	107.2 mm (4.2 in)
1969	199.4 mm (7.9 in)
1970	99.6 mm (3.9 in)
1971	160.5 mm (6.3 in)
1972	68.8 mm (2.7 in)
1980	32.4 mm (1.3 in)
1981	126.0 mm (5.0 in)
1982	244.9 mm (9.6 in)
1983	133.2 mm (5.2 in)
1984	273.9 mm (10.8 in)
1985	164.8 mm (6.5 in)
1986	265.3 mm (10.4 in)
1987	177.4 mm (7.0 in)
1988	85.4 mm (3.4 in)
1989	183.6 mm (7.2 in)
1990	72.2 mm (2.8 in)
1991	133.8 mm (5.3 in)
1992	43.4 mm (1.7 in)
1993	161.8 mm (6.4 in)
1994	114.2 mm (4.5 in)
1995	114.4 mm (4.5 in)
1996	236.4 mm (9.3 in)
1997	320.8 mm (12.6 in)

Longest dry spell (CDD)

The longest dry spell of the year at Derby Post Office, 1884 to 1997. The record is 302 days in 1924, marked on the chart; the median year is 143 days.

Longest dry spell (CDD) at Derby Post Office by year
Year	Longest dry spell (CDD)
1884	92 days
1885	30 days
1886	92 days
1887	123 days
1888	61 days
1889	92 days
1890	92 days
1891	123 days
1892	244 days
1893	123 days
1894	92 days
1895	61 days
1896	61 days
1897	123 days
1898	123 days
1899	31 days
1900	92 days
1901	92 days
1902	123 days
1903	214 days
1904	92 days
1905	31 days
1906	61 days
1907	85 days
1908	102 days
1909	146 days
1910	158 days
1911	157 days
1912	205 days
1913	158 days
1914	98 days
1915	151 days
1916	118 days
1917	181 days
1918	121 days
1919	129 days
1920	128 days
1921	176 days
1922	127 days
1923	119 days
1924	302 days
1925	115 days
1926	177 days
1927	116 days
1928	156 days
1929	184 days
1930	202 days
1931	152 days
1932	163 days
1933	114 days
1934	142 days
1935	123 days
1936	210 days
1937	155 days
1938	158 days
1939	145 days
1940	141 days
1941	153 days
1942	104 days
1943	99 days
1944	150 days
1945	117 days
1946	252 days
1947	148 days
1948	239 days
1949	185 days
1950	125 days
1951	171 days
1952	149 days
1953	200 days
1954	116 days
1955	114 days
1956	135 days
1957	116 days
1958	122 days
1959	226 days
1960	164 days
1961	199 days
1962	145 days
1963	105 days
1964	158 days
1965	107 days
1966	185 days
1967	153 days
1968	83 days
1969	214 days
1970	178 days
1971	174 days
1972	80 days
1980	182 days
1981	172 days
1982	232 days
1983	177 days
1984	251 days
1985	218 days
1986	75 days
1987	175 days
1988	150 days
1989	188 days
1990	188 days
1991	123 days
1992	154 days
1993	143 days
1994	143 days
1995	238 days
1996	134 days
1997	37 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.

Rainfall Return Levels

80 years, 1907 to 1996

A day with at least 78.9 mm (3.1 in) of rain is expected about once in 2 years. A day with at least 342.8 mm (13.5 in) of rain is expected about once in 100 years.

Rainfall return levels at Derby Post Office: the daily rain expected about once in a given number of years
Expected about once in	A day with at least	Note
2 years	78.9 mm (3.1 in)
5 years	123.2 mm (4.9 in)
10 years	161.0 mm (6.3 in)
25 years	220.9 mm (8.7 in)
50 years	276.4 mm (10.9 in)
100 years	342.8 mm (13.5 in)	Longer than the 80 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, 80 years of values from 1907 to 1996.

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: 418.3 mm (16.5 in) in 1917; 311.2 mm (12.3 in) in 1931; 251.7 mm (9.9 in) in 1932.

Download the Data

Data for Derby Post Office standing records by year: CSV or JSON. Field meanings are on the data page.
Data for Derby Post Office 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 2026-10-14 (14 October 2026). Records are computed by this site and are not official.

Data as of 2026-10-14. Last revised 14 October 2026 (2026-10-14).