Weather Records on 17 August 2021

800 weather records were set or tied worldwide on 17 August 2021. Highest significance: Nyhammar, SE.

Key Facts for 17 August 2021

On 17 August 2021, 800 weather records were set or tied at long-record stations worldwide.
353 were record highs and 147 were record lows, counting maximum and minimum temperature.
By timescale, 18 were all-time records, 26 monthly and 756 daily.
Nyhammar set an all-time record daily precipitation of 102.6 mm (4.0 in) on 17 August 2021.
Across 162 earlier years (1797 to 2026) the same calendar date averaged 472 records.

Record Map

800 stations

800 station records on 17 August 2021 are marked on the map, coloured by record type. Dot size shows the significance score. Made with Natural Earth.

Weather records on 17 August 2021: highest significance records shown on the map
Station	Country	Type	Value	Significance
Nyhammar	Sweden	Record daily precipitation	102.6 mm (4.0 in)	80 of 100 (Exceptional)
Sandviken	Sweden	Record daily precipitation	96.0 mm (3.8 in)	77 of 100 (Major)
Ludvika	Sweden	Record daily precipitation	63.9 mm (2.5 in)	67 of 100 (Major)
Leksand	Sweden	Record daily precipitation	55.0 mm (2.2 in)	67 of 100 (Major)
Hudiksvall	Sweden	Record daily precipitation	101.8 mm (4.0 in)	67 of 100 (Major)
Gavle-Abyggeby	Sweden	Record daily precipitation	117.2 mm (4.6 in)	65 of 100 (Major)
Landskrona_D	Sweden	Record daily precipitation	50.9 mm (2.0 in)	64 of 100 (Major)
Ockelbo	Sweden	Record daily precipitation	109.0 mm (4.3 in)	64 of 100 (Major)
Delsbo	Sweden	Record daily precipitation	82.4 mm (3.2 in)	64 of 100 (Major)
Falun	Sweden	Record daily precipitation	79.5 mm (3.1 in)	63 of 100 (Major)
Jarvso	Sweden	Record daily precipitation	81.5 mm (3.2 in)	63 of 100 (Major)
Forse	Sweden	Record daily precipitation	40.7 mm (1.6 in)	63 of 100 (Major)
Saigo	Japan	Record daily precipitation	168.9 mm (6.6 in)	62 of 100 (Major)
Bauska	Latvia	Record daily precipitation	39.9 mm (1.6 in)	62 of 100 (Major)
Klippan	Sweden	Record daily precipitation	80.1 mm (3.2 in)	62 of 100 (Major)
N Fk 2	United States	Record daily precipitation	159.5 mm (6.3 in)	61 of 100 (Major)
Tellico Plains	United States	Record daily precipitation	82.6 mm (3.3 in)	61 of 100 (Major)
Guba	Azerbaijan	Record daily precipitation	99.3 mm (3.9 in)	60 of 100 (Major)
Gulbene	Latvia	Record daily precipitation	30.5 mm (1.2 in)	60 of 100 (Major)
Hofors	Sweden	Record daily precipitation	110.5 mm (4.4 in)	60 of 100 (Major)
Newark Ag Farm	United States	Record daily precipitation	81.8 mm (3.2 in)	59 of 100 (Notable)
Adel	United States	Record daily precipitation	29.5 mm (1.2 in)	59 of 100 (Notable)
Trokorna	Sweden	Record daily precipitation	83.5 mm (3.3 in)	58 of 100 (Notable)
Satenas	Sweden	Record daily precipitation	45.8 mm (1.8 in)	57 of 100 (Notable)
Ft Benning Lawson Fld	United States	Record daily precipitation	94.7 mm (3.7 in)	56 of 100 (Notable)
Norberg	Sweden	Record daily precipitation	78.6 mm (3.1 in)	55 of 100 (Notable)
Akune	Japan	Record daily precipitation	242.1 mm (9.5 in)	52 of 100 (Notable)
Tanger	Sweden	Record daily precipitation	51.9 mm (2.0 in)	52 of 100 (Notable)
Newnan 7 WNW	United States	Record daily precipitation	104.6 mm (4.1 in)	52 of 100 (Notable)
Trial Lake	United States	Record daily precipitation	35.6 mm (1.4 in)	52 of 100 (Notable)
Riddarhyttan	Sweden	Record daily precipitation	38.0 mm (1.5 in)	50 of 100 (Notable)
Stalldalen	Sweden	Record daily precipitation	64.6 mm (2.5 in)	50 of 100 (Notable)
Kopparberg_D	Sweden	Record daily precipitation	49.6 mm (2.0 in)	49 of 100 (Notable)
Newport 1 NW	United States	Record daily precipitation	61.2 mm (2.4 in)	49 of 100 (Notable)
Lund	Sweden	Record daily precipitation	33.0 mm (1.3 in)	48 of 100 (Notable)
Stahl Peak	United States	Record daily precipitation	66.0 mm (2.6 in)	48 of 100 (Notable)
Wakayama	Japan	Record daily precipitation	183.9 mm (7.2 in)	47 of 100 (Notable)
Simea	Sweden	Record daily precipitation	63.4 mm (2.5 in)	47 of 100 (Notable)
Kuggoren A	Sweden	Record daily precipitation	84.5 mm (3.3 in)	47 of 100 (Notable)
Currant Creek	United States	Record daily precipitation	30.5 mm (1.2 in)	47 of 100 (Notable)
Gendalen	Sweden	Record daily precipitation	42.7 mm (1.7 in)	46 of 100 (Notable)
Traneberg	Sweden	Record daily precipitation	57.5 mm (2.3 in)	46 of 100 (Notable)
Fredriksberg	Sweden	Record daily precipitation	64.7 mm (2.5 in)	46 of 100 (Notable)
Knoxville AP	United States	Record daily precipitation	71.4 mm (2.8 in)	46 of 100 (Notable)
Intl Falls Intl AP	United States	Record high minimum temperature	21.7 C (71.1 F)	46 of 100 (Notable)
Kagoshima	Japan	Record daily precipitation	249.4 mm (9.8 in)	45 of 100 (Notable)
Avesta	Sweden	Record daily precipitation	73.1 mm (2.9 in)	45 of 100 (Notable)
Bristol AP	United States	Record daily precipitation	65.0 mm (2.6 in)	45 of 100 (Notable)
Hov	Sweden	Record daily precipitation	62.9 mm (2.5 in)	44 of 100 (Notable)
Lanna	Sweden	Record daily precipitation	39.6 mm (1.6 in)	44 of 100 (Notable)
Spansberget	Sweden	Record daily precipitation	85.7 mm (3.4 in)	44 of 100 (Notable)
Nianfors	Sweden	Record daily precipitation	112.2 mm (4.4 in)	44 of 100 (Notable)
Casa Grande Nm	United States	Record daily precipitation	35.6 mm (1.4 in)	44 of 100 (Notable)
Live Oak	United States	Record high minimum temperature	25.0 C (77.0 F)	44 of 100 (Notable)
Red Lake Indian Agcy	United States	Record high minimum temperature	21.7 C (71.1 F)	44 of 100 (Notable)
Brovallen	Sweden	Record daily precipitation	51.8 mm (2.0 in)	43 of 100 (Notable)
Finnbacka_D	Sweden	Record daily precipitation	48.1 mm (1.9 in)	43 of 100 (Notable)
Ft Meade	United States	Record high maximum temperature	39.4 C (102.9 F)	43 of 100 (Notable)
Vase_D	Sweden	Record daily precipitation	43.3 mm (1.7 in)	42 of 100 (Notable)
Intl Falls Intl AP	United States	Record high maximum temperature	33.3 C (91.9 F)	42 of 100 (Notable)

Counts by Type and Timescale

800 records

Records set or tied on 17 August 2021 by type: Highest daily maximum 156, Lowest daily maximum 113, Highest daily minimum 197, Lowest daily minimum 34, Heaviest daily rainfall 300.

Records on 17 August 2021 by type
Record type	Records
Highest daily maximum	156
Lowest daily maximum	113
Highest daily minimum	197
Lowest daily minimum	34
Heaviest daily rainfall	300
Heaviest daily snowfall	0
Deepest snow cover	0

Records on 17 August 2021 by timescale: all-time 18, monthly 26, daily 756.

How Much Records Were Beaten By

636 broken records

Margins by which the 636 broken records beat the old ones, in degrees Celsius for temperature and millimetres for precipitation and snow; the largest margin was 86.2. Ties are not counted.

Top 20 by Significance

17 August 2021

Top 20 records on 17 August 2021 by significance
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
17 August 2021	Nyhammar, SE	all-time rain	102.6 mm (4.0 in)	22.8 mm (0.9 in)	70 years	80 of 100 (Exceptional)
17 August 2021	Sandviken, SE	all-time rain	96.0 mm (3.8 in)	29.7 mm (1.2 in)	40 years	77 of 100 (Major)
17 August 2021	Ludvika, SE	monthly rain	63.9 mm (2.5 in)	17.8 mm (0.7 in)	80 years	67 of 100 (Major)
17 August 2021	Leksand, SE	monthly rain	55.0 mm (2.2 in)	18.4 mm (0.7 in)	70 years	67 of 100 (Major)
17 August 2021	Hudiksvall, SE	all-time rain	101.8 mm (4.0 in)	24.2 mm (1.0 in)	37 years	67 of 100 (Major)
17 August 2021	Gavle-Abyggeby, SE	all-time rain	117.2 mm (4.6 in)	27.5 mm (1.1 in)	24 years	65 of 100 (Major)
17 August 2021	Landskrona_D, SE	daily rain	50.9 mm (2.0 in)	29.7 mm (1.2 in)	59 years	64 of 100 (Major)
17 August 2021	Ockelbo, SE	all-time rain	109.0 mm (4.3 in)	24.0 mm (0.9 in)	28 years	64 of 100 (Major)
17 August 2021	Delsbo, SE	all-time rain	82.4 mm (3.2 in)	15.6 mm (0.6 in)	40 years	64 of 100 (Major)
17 August 2021	Falun, SE	daily rain	79.5 mm (3.1 in)	53.1 mm (2.1 in)	46 years	63 of 100 (Major)
17 August 2021	Jarvso, SE	all-time rain	81.5 mm (3.2 in)	17.8 mm (0.7 in)	35 years	63 of 100 (Major)
17 August 2021	Forse, SE	daily rain	40.7 mm (1.6 in)	17.4 mm (0.7 in)	96 years	63 of 100 (Major)
17 August 2021	Saigo, JP	daily rain	168.9 mm (6.6 in)	86.2 mm (3.4 in)	64 years	62 of 100 (Major)
17 August 2021	Bauska, LV	daily rain	39.9 mm (1.6 in)	28.3 mm (1.1 in)	54 years	62 of 100 (Major)
17 August 2021	Klippan, SE	daily rain	80.1 mm (3.2 in)	51.9 mm (2.0 in)	51 years	62 of 100 (Major)
17 August 2021	N Fk 2, US	monthly rain	159.5 mm (6.3 in)	70.1 mm (2.8 in)	12 years	61 of 100 (Major)
17 August 2021	Tellico Plains, US	daily rain	82.6 mm (3.3 in)	41.5 mm (1.6 in)	68 years	61 of 100 (Major)
17 August 2021	Guba, AZ	daily rain	99.3 mm (3.9 in)	62.3 mm (2.5 in)	40 years	60 of 100 (Major)
17 August 2021	Gulbene, LV	daily rain	30.5 mm (1.2 in)	23.7 mm (0.9 in)	54 years	60 of 100 (Major)
17 August 2021	Hofors, SE	daily rain	110.5 mm (4.4 in)	84.4 mm (3.3 in)	46 years	60 of 100 (Major)

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

1797 to 2021

Records set or tied on this calendar date in each year from 1797 to 2021. 2021 had 800 records.

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

Records on 08-17 in each year
Year	Records
1797	2
1802	2
1820	2
1837	1
1838	2
1841	2
1842	1
1845	2
1853	1
1854	1
1856	1
1857	1
1861	3
1862	1
1867	1
1868	3
1869	1
1872	1
1875	2
1876	5
1879	1
1881	1
1882	1
1883	2
1885	3
1886	1
1888	5
1891	1
1892	3
1893	2
1894	3
1895	2
1896	3
1897	1
1898	5
1899	8
1900	3
1901	14
1902	7
1903	6
1904	2
1905	11
1906	28
1907	9
1908	26
1909	24
1910	17
1911	18
1912	31
1913	79
1914	41
1915	28
1916	33
1917	35
1918	112
1919	37
1920	110
1921	37
1922	169
1923	161
1924	171
1925	130
1926	182
1927	228
1928	131
1929	243
1930	138
1931	302
1932	360
1933	260
1934	377
1935	437
1936	670
1937	726
1938	466
1939	364
1940	341
1941	378
1942	461
1943	743
1944	531
1945	387
1946	433
1947	682
1948	475
1949	371
1950	522
1951	413
1952	470
1953	345
1954	685
1955	465
1956	407
1957	504
1958	519
1959	543
1960	533
1961	998
1962	445
1963	650
1964	410
1965	641
1966	496
1967	679
1968	953
1969	593
1970	467
1971	447
1972	1,044
1973	750
1974	582
1975	612
1976	797
1977	1,216
1978	814
1979	1,464
1980	895
1981	1,112
1982	554
1983	1,574
1984	726
1985	948
1986	916
1987	1,150
1988	1,608
1989	687
1990	949
1991	560
1992	1,813
1993	803
1994	1,038
1995	1,724
1996	752
1997	1,544
1998	1,003
1999	697
2000	994
2001	1,101
2002	1,266
2003	948
2004	1,046
2005	722
2006	814
2007	1,646
2008	1,301
2009	922
2010	1,105
2011	956
2012	1,215
2013	802
2014	997
2015	890
2016	748
2017	544
2018	518
2019	467
2020	1,529
2021	800
2022	1,428
2023	1,032
2024	740
2025	538
2026	535

Download the Data

Data for records on 2021-08-17: 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 20	579
20 to 40	39
40 to 60	12
60 to 80	4
80 to 100	2