Weather Records on 20 December 1999

938 weather records were set or tied worldwide on 20 December 1999. Highest significance: Anchorage Merrill Fld, US.

Key Facts for 20 December 1999

On 20 December 1999, 938 weather records were set or tied at long-record stations worldwide.
241 were record highs and 292 were record lows, counting maximum and minimum temperature.
By timescale, 1 were all-time records, 28 monthly and 909 daily.
Anchorage Merrill Fld set a daily record snowfall of 31.8 cm (12.5 in) on 20 December 1999.
Across 163 earlier years (1793 to 2025) the same calendar date averaged 464 records.

Record Map

938 stations

938 station records on 20 December 1999 are marked on the map, coloured by record type. Dot size shows the significance score. Made with Natural Earth.

Weather records on 20 December 1999: highest significance records shown on the map
Station	Country	Type	Value	Significance
Anchorage Merrill Fld	United States	Record daily snowfall	31.8 cm (12.5 in)	72 of 100 (Major)
Bottineau	United States	Record daily snowfall	12.7 cm (5.0 in)	61 of 100 (Major)
Valdez WSO	United States	Record daily precipitation	59.4 mm (2.3 in)	60 of 100 (Major)
Chamingup	Australia	Record daily precipitation	62.0 mm (2.4 in)	59 of 100 (Notable)
Boyanup	Australia	Record daily precipitation	28.2 mm (1.1 in)	57 of 100 (Notable)
Buffalo	United States	Record daily snowfall	15.2 cm (6.0 in)	55 of 100 (Notable)
Cashmere Downs	Australia	Record daily precipitation	34.4 mm (1.4 in)	51 of 100 (Notable)
Aracas	Brazil	Record daily precipitation	87.0 mm (3.4 in)	51 of 100 (Notable)
Mayaguez City	Puerto Rico [United States]	Record low maximum temperature	25.6 C (78.1 F)	49 of 100 (Notable)
Northway AP	United States	Record daily snowfall	12.7 cm (5.0 in)	49 of 100 (Notable)
Deaver	United States	Record daily snowfall	7.6 cm (3.0 in)	47 of 100 (Notable)
Whitby Falls	Australia	Record daily precipitation	39.0 mm (1.5 in)	46 of 100 (Notable)
Tiririca	Brazil	Record daily precipitation	79.9 mm (3.1 in)	46 of 100 (Notable)
Galveston	United States	Record daily precipitation	78.7 mm (3.1 in)	46 of 100 (Notable)
Marriwood	Australia	Record daily precipitation	31.0 mm (1.2 in)	45 of 100 (Notable)
Katanning Comparison	Australia	Record daily precipitation	26.8 mm (1.1 in)	45 of 100 (Notable)
Davis 2 WSW Exp Farm	United States	Record high maximum temperature	22.2 C (72.0 F)	45 of 100 (Notable)
Kimberley Res.Station	Australia	Record daily precipitation	94.0 mm (3.7 in)	44 of 100 (Notable)
Briksdal	Norway	Record snow depth	70.0 cm (27.6 in)	44 of 100 (Notable)
Indianola 1SW	United States	Record daily snowfall	7.1 cm (2.8 in)	44 of 100 (Notable)
Vik I Sogn III	Norway	Record snow depth	55.0 cm (21.7 in)	43 of 100 (Notable)
Mason City	United States	Record daily snowfall	10.2 cm (4.0 in)	43 of 100 (Notable)
Caledonia	United States	Record daily precipitation	35.6 mm (1.4 in)	43 of 100 (Notable)
Ivanhoe Station	Australia	Record daily precipitation	93.0 mm (3.7 in)	41 of 100 (Notable)
Nhill	Australia	Record low minimum temperature	2.3 C (36.1 F)	41 of 100 (Notable)
Finca Hamburgo	Mexico	Record daily precipitation	119.9 mm (4.7 in)	41 of 100 (Notable)
Berkeley	United States	Record high maximum temperature	22.8 C (73.0 F)	41 of 100 (Notable)
Smithfield	United States	Record daily precipitation	31.8 mm (1.3 in)	41 of 100 (Notable)
Auvergne	Australia	Record daily precipitation	101.6 mm (4.0 in)	40 of 100 (Notable)
Fushiki	Japan	Record daily precipitation	53.1 mm (2.1 in)	40 of 100 (Notable)
Hovlandsdal	Norway	Record snow depth	53.0 cm (20.9 in)	40 of 100 (Notable)
Cle Elum	United States	Record high minimum temperature	4.4 C (39.9 F)	39 of 100 (Notable)
Margaret River Station	Australia	Record daily precipitation	52.0 mm (2.0 in)	38 of 100 (Notable)
Newport Beach Harbor	United States	Record high minimum temperature	16.7 C (62.1 F)	38 of 100 (Notable)
Strathmore	Australia	Record daily precipitation	86.0 mm (3.4 in)	37 of 100 (Notable)
Boone	United States	Record daily snowfall	7.6 cm (3.0 in)	37 of 100 (Notable)
Chico UNIV Farm	United States	Record high maximum temperature	23.9 C (75.0 F)	36 of 100 (Notable)
Napa State Hospital	United States	Record high maximum temperature	24.4 C (75.9 F)	36 of 100 (Notable)
Red Oak	United States	Record daily snowfall	10.2 cm (4.0 in)	36 of 100 (Notable)
San Francisco Dwtn	United States	Record high maximum temperature	22.2 C (72.0 F)	36 of 100 (Notable)
Valdez WSO	United States	Record daily snowfall	45.2 cm (17.8 in)	36 of 100 (Notable)
Toyama	Japan	Record daily precipitation	43.9 mm (1.7 in)	35 of 100 (Notable)
Kentfield	United States	Record high maximum temperature	22.8 C (73.0 F)	35 of 100 (Notable)
Creston 2 SW	United States	Record daily snowfall	14.0 cm (5.5 in)	35 of 100 (Notable)
Galesville 2WSW	United States	Record daily precipitation	40.6 mm (1.6 in)	35 of 100 (Notable)
Ahuacatlan	Mexico	Record low minimum temperature	2.8 C (37.0 F)	34 of 100 (Routine)
Skjak	Norway	Record snow depth	65.0 cm (25.6 in)	34 of 100 (Routine)
Graton	United States	Record high maximum temperature	25.0 C (77.0 F)	34 of 100 (Routine)
Zumbrota	United States	Record daily snowfall	10.2 cm (4.0 in)	34 of 100 (Routine)
Milan	United States	Record daily precipitation	50.8 mm (2.0 in)	34 of 100 (Routine)
River Falls	United States	Record daily snowfall	8.9 cm (3.5 in)	34 of 100 (Routine)
Brindisi	Italy	Record daily precipitation	32.8 mm (1.3 in)	33 of 100 (Routine)
Tangancicuaro	Mexico	Record high minimum temperature	15.0 C (59.0 F)	33 of 100 (Routine)
Santa Cruz de Alaya	Mexico	Record low minimum temperature	5.0 C (41.0 F)	33 of 100 (Routine)
Lakeport	United States	Record high maximum temperature	22.8 C (73.0 F)	33 of 100 (Routine)
Orland	United States	Record high minimum temperature	12.8 C (55.0 F)	33 of 100 (Routine)
Potter Valley Powerhouse	United States	Record high maximum temperature	25.6 C (78.1 F)	33 of 100 (Routine)
Vacaville	United States	Record high maximum temperature	24.4 C (75.9 F)	33 of 100 (Routine)
Wabasha	United States	Record daily snowfall	12.7 cm (5.0 in)	33 of 100 (Routine)
Pahrump 4 NW	United States	Record high minimum temperature	6.7 C (44.1 F)	33 of 100 (Routine)

Counts by Type and Timescale

938 records

Records set or tied on 20 December 1999 by type: Highest daily maximum 167, Lowest daily maximum 103, Highest daily minimum 74, Lowest daily minimum 189, Heaviest daily rainfall 237, Heaviest daily snowfall 102, Deepest snow cover 66.

Records on 20 December 1999 by type
Record type	Records
Highest daily maximum	167
Lowest daily maximum	103
Highest daily minimum	74
Lowest daily minimum	189
Heaviest daily rainfall	237
Heaviest daily snowfall	102
Deepest snow cover	66

Records on 20 December 1999 by timescale: all-time 1, monthly 28, daily 909.

How Much Records Were Beaten By

746 broken records

Margins by which the 746 broken records beat the old ones, in degrees Celsius for temperature and millimetres for precipitation and snow; the largest margin was 280.0. Ties are not counted.

Top 20 by Significance

20 December 1999

Top 20 records on 20 December 1999 by significance
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
20 December 1999	Anchorage Merrill Fld, US	daily snowfall	31.8 cm (12.5 in)	28.0 cm (11.0 in)	82 years	72 of 100 (Major)
20 December 1999	Bottineau, US	daily snowfall	12.7 cm (5.0 in)	7.1 cm (2.8 in)	86 years	61 of 100 (Major)
20 December 1999	Valdez WSO, US	daily rain	59.4 mm (2.3 in)	37.3 mm (1.5 in)	76 years	60 of 100 (Major)
20 December 1999	Chamingup, AU	monthly rain	62.0 mm (2.4 in)	17.3 mm (0.7 in)	39 years	59 of 100 (Notable)
20 December 1999	Boyanup, AU	daily rain	28.2 mm (1.1 in)	12.7 mm (0.5 in)	85 years	57 of 100 (Notable)
20 December 1999	Buffalo, US	daily snowfall	15.2 cm (6.0 in)	10.1 cm (4.0 in)	81 years	55 of 100 (Notable)
20 December 1999	Cashmere Downs, AU	daily rain	34.4 mm (1.4 in)	26.0 mm (1.0 in)	16 years	51 of 100 (Notable)
20 December 1999	Aracas, BR	daily rain	87.0 mm (3.4 in)	67.0 mm (2.6 in)	29 years	51 of 100 (Notable)
20 December 1999	Mayaguez City, PR	daily low max	25.6 C (78.1 F)	1.6 C (2.9 F)	96 years	49 of 100 (Notable)
20 December 1999	Northway AP, US	daily snowfall	12.7 cm (5.0 in)	8.6 cm (3.4 in)	20 years	49 of 100 (Notable)
20 December 1999	Deaver, US	daily snowfall	7.6 cm (3.0 in)	5.1 cm (2.0 in)	69 years	47 of 100 (Notable)
20 December 1999	Whitby Falls, AU	monthly rain	39.0 mm (1.5 in)	7.5 mm (0.30 in)	55 years	46 of 100 (Notable)
20 December 1999	Tiririca, BR	daily rain	79.9 mm (3.1 in)	63.9 mm (2.5 in)	29 years	46 of 100 (Notable)
20 December 1999	Galveston, US	daily rain	78.7 mm (3.1 in)	44.2 mm (1.7 in)	36 years	46 of 100 (Notable)
20 December 1999	Marriwood, AU	daily rain	31.0 mm (1.2 in)	20.1 mm (0.8 in)	33 years	45 of 100 (Notable)
20 December 1999	Katanning Comparison, AU	daily rain	26.8 mm (1.1 in)	6.5 mm (0.26 in)	85 years	45 of 100 (Notable)
20 December 1999	Davis 2 WSW Exp Farm, US	daily high max	22.2 C (72.0 F)	2.2 C (4.0 F)	102 years	45 of 100 (Notable)
20 December 1999	Kimberley Res.Station, AU	daily rain	94.0 mm (3.7 in)	56.8 mm (2.2 in)	9 years	44 of 100 (Notable)
20 December 1999	Briksdal, NO	monthly snow depth	70.0 cm (27.6 in)	13.0 cm (5.1 in)	55 years	44 of 100 (Notable)
20 December 1999	Indianola 1SW, US	daily snowfall	7.1 cm (2.8 in)	2.0 cm (0.8 in)	101 years	44 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

1793 to 1999

Records set or tied on this calendar date in each year from 1793 to 1999. 1999 had 938 records.

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

Records on 12-20 in each year
Year	Records
1793	1
1795	1
1804	1
1805	2
1808	1
1815	1
1828	1
1837	1
1846	1
1855	8
1858	1
1860	1
1866	1
1867	1
1868	1
1869	1
1871	2
1874	3
1875	1
1877	2
1878	1
1879	1
1880	1
1881	1
1882	1
1884	4
1885	1
1886	4
1889	4
1890	2
1891	2
1892	1
1894	2
1895	8
1896	1
1897	4
1898	2
1899	1
1900	7
1901	8
1902	14
1903	17
1904	9
1905	5
1906	5
1907	11
1908	5
1909	22
1910	17
1911	24
1912	27
1913	7
1914	43
1915	18
1916	45
1917	33
1918	18
1919	25
1920	22
1921	101
1922	88
1923	215
1924	332
1925	96
1926	163
1927	200
1928	93
1929	256
1930	67
1931	536
1932	170
1933	492
1934	265
1935	152
1936	416
1937	181
1938	240
1939	308
1940	965
1941	633
1942	817
1943	193
1944	340
1945	430
1946	327
1947	385
1948	345
1949	1,141
1950	758
1951	926
1952	394
1953	385
1954	416
1955	726
1956	471
1957	1,354
1958	382
1959	142
1960	354
1961	369
1962	475
1963	875
1964	499
1965	353
1966	555
1967	1,370
1968	482
1969	514
1970	518
1971	441
1972	448
1973	1,184
1974	328
1975	610
1976	382
1977	484
1978	910
1979	600
1980	667
1981	1,681
1982	712
1983	2,995
1984	1,411
1985	1,035
1986	321
1987	1,179
1988	760
1989	1,812
1990	1,885
1991	1,172
1992	1,134
1993	1,266
1994	813
1995	1,128
1996	1,448
1997	651
1998	1,110
1999	938
2000	1,150
2001	523
2002	943
2003	1,315
2004	836
2005	515
2006	1,387
2007	986
2008	1,356
2009	1,502
2010	2,055
2011	846
2012	1,131
2013	584
2014	524
2015	1,238
2016	603
2017	688
2018	592
2019	731
2020	554
2021	442
2022	567
2023	1,242
2024	897
2025	1,166

Download the Data

Data for records on 1999-12-20: 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 50	695
50 to 100	32
100 to 150	10
150 to 200	6
200 to 250	1
250 to 300	2