Weather Records on 18 September 1999

583 weather records were set or tied worldwide on 18 September 1999. Highest significance: Ponferrada, ES.

Key Facts for 18 September 1999

On 18 September 1999, 583 weather records were set or tied at long-record stations worldwide.
210 were record highs and 232 were record lows, counting maximum and minimum temperature.
By timescale, 3 were all-time records, 17 monthly and 563 daily.
Ponferrada set a daily record precipitation of 54.4 mm (2.1 in) on 18 September 1999.
Across 163 earlier years (1803 to 2026) the same calendar date averaged 420 records.

Record Map

583 stations

583 station records on 18 September 1999 are marked on the map, coloured by record type. Dot size shows the significance score. Made with Natural Earth.

Weather records on 18 September 1999: highest significance records shown on the map
Station	Country	Type	Value	Significance
Ponferrada	Spain	Record daily precipitation	54.4 mm (2.1 in)	57 of 100 (Notable)
Canaan	United States	Record daily precipitation	97.5 mm (3.8 in)	57 of 100 (Notable)
Porto	Portugal	Record daily precipitation	70.0 mm (2.8 in)	50 of 100 (Notable)
Coimbra	Portugal	Record daily precipitation	45.5 mm (1.8 in)	48 of 100 (Notable)
Karlshamn	Sweden	Record daily precipitation	27.5 mm (1.1 in)	48 of 100 (Notable)
Ixcateopan de Tlapa	Mexico	Record daily precipitation	84.8 mm (3.3 in)	46 of 100 (Notable)
Braganca	Portugal	Record daily precipitation	43.8 mm (1.7 in)	46 of 100 (Notable)
Renison Bell	Australia	Record daily precipitation	50.2 mm (2.0 in)	45 of 100 (Notable)
Santiago de Compostela/Labacol	Spain	Record daily precipitation	66.0 mm (2.6 in)	45 of 100 (Notable)
New Orleans Audubon	United States	Record low minimum temperature	11.7 C (53.1 F)	45 of 100 (Notable)
Vigo Peinador	Spain	Record daily precipitation	93.0 mm (3.7 in)	43 of 100 (Notable)
Chelsea	United States	Record low maximum temperature	10.6 C (51.1 F)	41 of 100 (Notable)
Port Alexander	United States	Record daily precipitation	198.4 mm (7.8 in)	40 of 100 (Notable)
Yinchuan	China	Record daily precipitation	33.0 mm (1.3 in)	39 of 100 (Notable)
Abelardo L. Rodriguez	Mexico	Record daily precipitation	47.8 mm (1.9 in)	39 of 100 (Notable)
White Sands Natl Mon	United States	Record low maximum temperature	20.0 C (68.0 F)	39 of 100 (Notable)
Georgetown 2 E	United States	Record low minimum temperature	11.1 C (52.0 F)	39 of 100 (Notable)
Atbasar	Kazakhstan	Record high minimum temperature	12.5 C (54.5 F)	38 of 100 (Notable)
Dyer 5S	United States	Record daily precipitation	40.6 mm (1.6 in)	38 of 100 (Notable)
Santa Cruz	United States	Record low maximum temperature	16.1 C (61.0 F)	37 of 100 (Notable)
First Connecticut Lake	United States	Record daily precipitation	42.4 mm (1.7 in)	37 of 100 (Notable)
Newberry	United States	Record low minimum temperature	7.8 C (46.0 F)	37 of 100 (Notable)
Buenavista	Mexico	Record high minimum temperature	21.7 C (71.1 F)	36 of 100 (Notable)
Lugo/Rozas	Spain	Record daily precipitation	73.4 mm (2.9 in)	36 of 100 (Notable)
Solvesborg	Sweden	Record daily precipitation	25.0 mm (1.0 in)	36 of 100 (Notable)
Live Oak	United States	Record daily precipitation	50.8 mm (2.0 in)	36 of 100 (Notable)
Kinston 7 SE	United States	Record low maximum temperature	17.2 C (63.0 F)	36 of 100 (Notable)
Bailing-Miao	China	Record daily precipitation	53.5 mm (2.1 in)	35 of 100 (Notable)
Comitan (Dge)	Mexico	Record daily precipitation	60.2 mm (2.4 in)	35 of 100 (Notable)
Lisbon	United States	Record daily precipitation	86.9 mm (3.4 in)	34 of 100 (Routine)
Las Vegas Muni AP	United States	Record daily precipitation	37.1 mm (1.5 in)	34 of 100 (Routine)
Beja	Portugal	Record daily precipitation	60.2 mm (2.4 in)	33 of 100 (Routine)
Clermont 9 S	United States	Record low minimum temperature	16.1 C (61.0 F)	33 of 100 (Routine)
Inverness 3 SE	United States	Record low minimum temperature	12.8 C (55.0 F)	33 of 100 (Routine)
Long Falls Dam	United States	Record daily precipitation	33.8 mm (1.3 in)	33 of 100 (Routine)
Cuautla (Smn)	Mexico	Record high minimum temperature	21.7 C (71.1 F)	32 of 100 (Routine)
L F Wade Intl AP Kindley Fld	Bermuda [United Kingdom]	Record daily precipitation	39.9 mm (1.6 in)	31 of 100 (Routine)
La Concha	Mexico	Record low minimum temperature	18.9 C (66.0 F)	31 of 100 (Routine)
Macuspana (Dge)	Mexico	Record daily precipitation	92.7 mm (3.6 in)	31 of 100 (Routine)
Ourense	Spain	Record daily precipitation	70.5 mm (2.8 in)	31 of 100 (Routine)
Saint Bernard	United States	Record low minimum temperature	5.0 C (41.0 F)	31 of 100 (Routine)
Lewisburg Exp STN	United States	Record low minimum temperature	2.2 C (36.0 F)	31 of 100 (Routine)
Jurh	China	Record daily precipitation	40.2 mm (1.6 in)	30 of 100 (Routine)
Las Margaritas	Mexico	Record daily precipitation	48.3 mm (1.9 in)	30 of 100 (Routine)
Huetamo	Mexico	Record low maximum temperature	25.0 C (77.0 F)	30 of 100 (Routine)
Ojai	United States	Record low maximum temperature	18.3 C (64.9 F)	30 of 100 (Routine)
Anchorage Merrill Fld	United States	Record high minimum temperature	9.4 C (48.9 F)	30 of 100 (Routine)
Los Angeles Downtown/Usc	United States	Record low maximum temperature	18.9 C (66.0 F)	30 of 100 (Routine)
Zeehan (West Coast Pioneers Mu	Australia	Record daily precipitation	59.0 mm (2.3 in)	29 of 100 (Routine)
Temascaltepec	Mexico	Record daily precipitation	47.2 mm (1.9 in)	29 of 100 (Routine)
Pueblo Nuevo	Mexico	Record daily precipitation	113.8 mm (4.5 in)	29 of 100 (Routine)
Roros	Norway	Record high minimum temperature	9.0 C (48.2 F)	29 of 100 (Routine)
Loggerheads: Colomendy Centre	United Kingdom	Record daily precipitation	46.2 mm (1.8 in)	29 of 100 (Routine)
Lyonshall	United Kingdom	Record daily precipitation	53.3 mm (2.1 in)	29 of 100 (Routine)
Haines AP	United States	Record high minimum temperature	11.1 C (52.0 F)	29 of 100 (Routine)
Guanacevi (Smn)	Mexico	Record high maximum temperature	30.6 C (87.1 F)	28 of 100 (Routine)
Tenango de Doria	Mexico	Record high maximum temperature	30.0 C (86.0 F)	28 of 100 (Routine)
Pericos	Mexico	Record daily precipitation	71.4 mm (2.8 in)	28 of 100 (Routine)
Tiree	United Kingdom	Record high maximum temperature	18.5 C (65.3 F)	28 of 100 (Routine)
Chester 1 SE	United States	Record low minimum temperature	8.3 C (46.9 F)	28 of 100 (Routine)

Counts by Type and Timescale

583 records

Records set or tied on 18 September 1999 by type: Highest daily maximum 89, Lowest daily maximum 79, Highest daily minimum 121, Lowest daily minimum 153, Heaviest daily rainfall 141.

Records on 18 September 1999 by type
Record type	Records
Highest daily maximum	89
Lowest daily maximum	79
Highest daily minimum	121
Lowest daily minimum	153
Heaviest daily rainfall	141
Heaviest daily snowfall	0
Deepest snow cover	0

Records on 18 September 1999 by timescale: all-time 3, monthly 17, daily 563.

How Much Records Were Beaten By

441 broken records

Margins by which the 441 broken records beat the old ones, in degrees Celsius for temperature and millimetres for precipitation and snow; the largest margin was 75.7. Ties are not counted.

Top 20 by Significance

18 September 1999

Top 20 records on 18 September 1999 by significance
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
18 September 1999	Ponferrada, ES	daily rain	54.4 mm (2.1 in)	42.5 mm (1.7 in)	44 years	57 of 100 (Notable)
18 September 1999	Canaan, US	daily rain	97.5 mm (3.8 in)	75.7 mm (3.0 in)	36 years	57 of 100 (Notable)
18 September 1999	Porto, PT	daily rain	70.0 mm (2.8 in)	32.1 mm (1.3 in)	52 years	50 of 100 (Notable)
18 September 1999	Coimbra, PT	daily rain	45.5 mm (1.8 in)	39.2 mm (1.5 in)	8 years	48 of 100 (Notable)
18 September 1999	Karlshamn, SE	daily rain	27.5 mm (1.1 in)	4.5 mm (0.18 in)	120 years	48 of 100 (Notable)
18 September 1999	Ixcateopan de Tlapa, MX	daily rain	84.8 mm (3.3 in)	56.4 mm (2.2 in)	8 years	46 of 100 (Notable)
18 September 1999	Braganca, PT	daily rain	43.8 mm (1.7 in)	21.4 mm (0.8 in)	45 years	46 of 100 (Notable)
18 September 1999	Renison Bell, AU	daily rain	50.2 mm (2.0 in)	13.1 mm (0.5 in)	76 years	45 of 100 (Notable)
18 September 1999	Santiago de Compostela/Labacol, ES	daily rain	66.0 mm (2.6 in)	50.4 mm (2.0 in)	16 years	45 of 100 (Notable)
18 September 1999	New Orleans Audubon, US	daily low min	11.7 C (53.1 F)	2.2 C (4.0 F)	96 years	45 of 100 (Notable)
18 September 1999	Vigo Peinador, ES	daily rain	93.0 mm (3.7 in)	55.2 mm (2.2 in)	17 years	43 of 100 (Notable)
18 September 1999	Chelsea, US	daily low max	10.6 C (51.1 F)	0.5 C (0.9 F)	101 years	41 of 100 (Notable)
18 September 1999	Port Alexander, US	all-time rain	198.4 mm (7.8 in)	4.9 mm (0.19 in)	47 years	40 of 100 (Notable)
18 September 1999	Yinchuan, CN	daily rain	33.0 mm (1.3 in)	13.9 mm (0.5 in)	41 years	39 of 100 (Notable)
18 September 1999	Abelardo L. Rodriguez, MX	daily rain	47.8 mm (1.9 in)	22.4 mm (0.9 in)	54 years	39 of 100 (Notable)
18 September 1999	White Sands Natl Mon, US	daily low max	20.0 C (68.0 F)	5.6 C (10.1 F)	58 years	39 of 100 (Notable)
18 September 1999	Georgetown 2 E, US	daily low min	11.1 C (52.0 F)	1.1 C (2.0 F)	88 years	39 of 100 (Notable)
18 September 1999	Atbasar, KZ	daily high min	12.5 C (54.5 F)	0.8 C (1.4 F)	94 years	38 of 100 (Notable)
18 September 1999	Dyer 5S, US	monthly rain	40.6 mm (1.6 in)	6.8 mm (0.27 in)	31 years	38 of 100 (Notable)
18 September 1999	Santa Cruz, US	daily low max	16.1 C (61.0 F)	0.6 C (1.1 F)	89 years	37 of 100 (Notable)

Significance is a score from 0 to 100 combining margin, the age of the old record and the length of the station's record. How it is computed.

The Same Date in Other Years

1803 to 1999

Records set or tied on this calendar date in each year from 1803 to 1999. 1999 had 583 records.

Counts for years before the ledger starts come from the same station rules.

Records on 09-18 in each year
Year	Records
1803	1
1811	1
1814	1
1819	1
1829	1
1832	1
1834	1
1835	1
1837	2
1847	2
1848	1
1849	1
1851	4
1859	1
1861	1
1865	1
1869	1
1871	1
1875	1
1876	2
1877	1
1879	1
1880	1
1881	1
1882	1
1885	1
1886	4
1889	6
1890	1
1891	1
1893	4
1894	2
1895	2
1896	4
1897	3
1898	5
1899	3
1900	2
1901	10
1902	8
1903	58
1904	6
1905	22
1906	16
1907	4
1908	11
1909	17
1910	5
1911	8
1912	43
1913	44
1914	56
1915	41
1916	58
1917	99
1918	57
1919	48
1920	56
1921	213
1922	45
1923	114
1924	62
1925	269
1926	205
1927	189
1928	114
1929	309
1930	124
1931	429
1932	226
1933	370
1934	188
1935	281
1936	155
1937	422
1938	373
1939	190
1940	402
1941	318
1942	1,001
1943	624
1944	503
1945	732
1946	576
1947	927
1948	427
1949	356
1950	370
1951	320
1952	340
1953	245
1954	446
1955	672
1956	587
1957	429
1958	491
1959	829
1960	351
1961	478
1962	360
1963	453
1964	282
1965	1,172
1966	498
1967	357
1968	763
1969	424
1970	377
1971	1,245
1972	691
1973	593
1974	559
1975	976
1976	615
1977	619
1978	1,162
1979	709
1980	652
1981	1,671
1982	603
1983	936
1984	951
1985	636
1986	730
1987	1,244
1988	997
1989	778
1990	904
1991	1,377
1992	821
1993	747
1994	852
1995	935
1996	1,237
1997	935
1998	1,038
1999	583
2000	1,146
2001	993
2002	828
2003	815
2004	1,027
2005	781
2006	1,309
2007	670
2008	697
2009	692
2010	1,040
2011	1,050
2012	922
2013	666
2014	682
2015	934
2016	893
2017	518
2018	1,200
2019	768
2020	682
2021	582
2022	613
2023	639
2024	687
2025	471
2026	864

Download the Data

Data for records on 1999-09-18: CSV or JSON. Field meanings are on the data page.

Sources: 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)) Made with Natural Earth. Public domain map data. Borders are Natural Earth's de facto depiction. Data as of 2026-10-17 (17 October 2026). Records are computed by this site and are not official.

Data as of 2026-10-16. Last revised 16 October 2026 (2026-10-16).

Margin	Records
0 to 10	398
10 to 20	17
20 to 30	14
30 to 40	5
40 to 50	3
50 to 60	3
60 to 70	0
70 to 80	1