Weather Records on 21 July 1977

708 weather records were set or tied worldwide on 21 July 1977. Highest significance: Mantova, IT.

Key Facts for 21 July 1977

On 21 July 1977, 708 weather records were set or tied at long-record stations worldwide.
438 were record highs and 88 were record lows, counting maximum and minimum temperature.
By timescale, 14 were all-time records, 28 monthly and 666 daily.
Mantova set a daily record precipitation of 31.4 mm (1.2 in) on 21 July 1977.
Across 159 earlier years (1794 to 2026) the same calendar date averaged 465 records.

Record Map

708 stations

708 station records on 21 July 1977 are marked on the map, coloured by record type. Dot size shows the significance score. Made with Natural Earth.

Weather records on 21 July 1977: highest significance records shown on the map
Station	Country	Type	Value	Significance
Mantova	Italy	Record daily precipitation	31.4 mm (1.2 in)	53 of 100 (Notable)
Hanty-Mansijsk	Russia	Record daily precipitation	44.0 mm (1.7 in)	53 of 100 (Notable)
Setauket Strong	United States	Record high maximum temperature	37.2 C (99.0 F)	53 of 100 (Notable)
Boulder	United States	Record daily precipitation	55.4 mm (2.2 in)	52 of 100 (Notable)
Huntingdon	Canada	Record high minimum temperature	24.4 C (75.9 F)	51 of 100 (Notable)
Mapleton No.2	United States	Record daily precipitation	100.3 mm (3.9 in)	50 of 100 (Notable)
Eureka	United States	Record daily precipitation	32.0 mm (1.3 in)	50 of 100 (Notable)
Hartford Wwtp	United States	Record daily precipitation	65.8 mm (2.6 in)	50 of 100 (Notable)
Camargo (Smn)	Mexico	Record daily precipitation	30.0 mm (1.2 in)	48 of 100 (Notable)
Blanding	United States	Record daily precipitation	26.7 mm (1.1 in)	44 of 100 (Notable)
Waterdale	United States	Record daily precipitation	51.8 mm (2.0 in)	43 of 100 (Notable)
Darlington	United States	Record high maximum temperature	42.2 C (108.0 F)	41 of 100 (Notable)
Newark Liberty Intl AP	United States	Record high maximum temperature	38.9 C (102.0 F)	41 of 100 (Notable)
Bluff City 3 SW	United States	Record daily precipitation	82.0 mm (3.2 in)	40 of 100 (Notable)
Helvecia (Efbm)	Brazil	Record daily precipitation	58.4 mm (2.3 in)	39 of 100 (Notable)
Huntington	United States	Record daily precipitation	50.3 mm (2.0 in)	39 of 100 (Notable)
Rockport 1 ESE	United States	Record high minimum temperature	25.0 C (77.0 F)	39 of 100 (Notable)
Penn Yan	United States	Record high minimum temperature	25.6 C (78.1 F)	39 of 100 (Notable)
Coldwater St School	United States	Record daily precipitation	33.3 mm (1.3 in)	38 of 100 (Notable)
Ewing	United States	Record daily precipitation	49.0 mm (1.9 in)	38 of 100 (Notable)
Sheboygan	United States	Record daily precipitation	55.6 mm (2.2 in)	38 of 100 (Notable)
St Andrews	Canada	Record high maximum temperature	31.7 C (89.1 F)	37 of 100 (Notable)
San Felipe	Mexico	Record low minimum temperature	10.6 C (51.1 F)	37 of 100 (Notable)
Cakir	Russia	Record daily precipitation	47.3 mm (1.9 in)	37 of 100 (Notable)
Dulce	United States	Record daily precipitation	32.8 mm (1.3 in)	37 of 100 (Notable)
Bedford	United States	Record high minimum temperature	24.4 C (75.9 F)	37 of 100 (Notable)
Adams	United States	Record high maximum temperature	33.9 C (93.0 F)	36 of 100 (Notable)
Goldsboro 4 SE	United States	Record high minimum temperature	26.1 C (79.0 F)	36 of 100 (Notable)
Fredericton Cda	Canada	Record high minimum temperature	22.0 C (71.6 F)	35 of 100 (Notable)
Meoqui (Smn)	Mexico	Record daily precipitation	35.3 mm (1.4 in)	35 of 100 (Notable)
Eastport	United States	Record high maximum temperature	31.7 C (89.1 F)	35 of 100 (Notable)
Denton 2 E	United States	Record high minimum temperature	24.4 C (75.9 F)	35 of 100 (Notable)
Lawrence	United States	Record high minimum temperature	23.9 C (75.0 F)	35 of 100 (Notable)
Gloversville	United States	Record high minimum temperature	23.3 C (73.9 F)	35 of 100 (Notable)
Santaquin Chlorinator	United States	Record low maximum temperature	21.1 C (70.0 F)	35 of 100 (Notable)
Ojo Caliente	Mexico	Record daily precipitation	51.8 mm (2.0 in)	34 of 100 (Routine)
Nashua 2 NNW	United States	Record high minimum temperature	23.3 C (73.9 F)	34 of 100 (Routine)
Saint Johnsbury	United States	Record high maximum temperature	37.2 C (99.0 F)	34 of 100 (Routine)
Farmville	United States	Record high maximum temperature	38.9 C (102.0 F)	34 of 100 (Routine)
Brockton	United States	Record high maximum temperature	35.6 C (96.1 F)	33 of 100 (Routine)
Durham	United States	Record high minimum temperature	21.7 C (71.1 F)	33 of 100 (Routine)
Alfred	United States	Record high minimum temperature	21.7 C (71.1 F)	33 of 100 (Routine)
Canandaigua 3 S	United States	Record high minimum temperature	25.0 C (77.0 F)	33 of 100 (Routine)
Plattsburgh AFB	United States	Record high maximum temperature	36.1 C (97.0 F)	33 of 100 (Routine)
Nashville	United States	Record high minimum temperature	25.0 C (77.0 F)	33 of 100 (Routine)
Warsaw 2 NW	United States	Record high minimum temperature	23.9 C (75.0 F)	33 of 100 (Routine)
New Hampton	United States	Record daily precipitation	46.5 mm (1.8 in)	32 of 100 (Routine)
Bethlehem	United States	Record high maximum temperature	33.3 C (91.9 F)	32 of 100 (Routine)
Dobbs Ferry-Ardsley	United States	Record high maximum temperature	39.4 C (102.9 F)	32 of 100 (Routine)
Roxboro 7 ESE	United States	Record high maximum temperature	38.3 C (100.9 F)	32 of 100 (Routine)
Chambersburg 1 ESE	United States	Record high minimum temperature	22.2 C (72.0 F)	32 of 100 (Routine)
Chute Hemmings	Canada	Record low maximum temperature	10.6 C (51.1 F)	31 of 100 (Routine)
El Cuije	Mexico	Record daily precipitation	31.8 mm (1.3 in)	31 of 100 (Routine)
Fremont	United States	Record daily precipitation	40.6 mm (1.6 in)	31 of 100 (Routine)
Taylor	United States	Record daily precipitation	50.8 mm (2.0 in)	31 of 100 (Routine)
Berlin	United States	Record high maximum temperature	34.4 C (93.9 F)	31 of 100 (Routine)
Mt Airy 2 W	United States	Record high minimum temperature	21.1 C (70.0 F)	31 of 100 (Routine)
Ephrata	United States	Record high minimum temperature	23.9 C (75.0 F)	31 of 100 (Routine)
Ottawa Cda	Canada	Record high minimum temperature	24.0 C (75.2 F)	30 of 100 (Routine)
Keams Canyon	United States	Record high maximum temperature	38.9 C (102.0 F)	30 of 100 (Routine)

Counts by Type and Timescale

708 records

Records set or tied on 21 July 1977 by type: Highest daily maximum 190, Lowest daily maximum 57, Highest daily minimum 248, Lowest daily minimum 31, Heaviest daily rainfall 182.

Records on 21 July 1977 by type
Record type	Records
Highest daily maximum	190
Lowest daily maximum	57
Highest daily minimum	248
Lowest daily minimum	31
Heaviest daily rainfall	182
Heaviest daily snowfall	0
Deepest snow cover	0

Records on 21 July 1977 by timescale: all-time 14, monthly 28, daily 666.

How Much Records Were Beaten By

508 broken records

Margins by which the 508 broken records beat the old ones, in degrees Celsius for temperature and millimetres for precipitation and snow; the largest margin was 59.6. Ties are not counted.

Top 20 by Significance

21 July 1977

Top 20 records on 21 July 1977 by significance
Date	Station	Record	Value	Beat old record by	Old record stood	Significance
21 July 1977	Mantova, IT	daily rain	31.4 mm (1.2 in)	12.4 mm (0.5 in)	98 years	53 of 100 (Notable)
21 July 1977	Hanty-Mansijsk, RU	daily rain	44.0 mm (1.7 in)	27.9 mm (1.1 in)	34 years	53 of 100 (Notable)
21 July 1977	Setauket Strong, US	all-time high max	37.2 C (99.0 F)	0.5 C (0.9 F)	79 years	53 of 100 (Notable)
21 July 1977	Boulder, US	daily rain	55.4 mm (2.2 in)	42.4 mm (1.7 in)	16 years	52 of 100 (Notable)
21 July 1977	Huntingdon, CA	monthly high min	24.4 C (75.9 F)	0.5 C (0.9 F)	101 years	51 of 100 (Notable)
21 July 1977	Mapleton No.2, US	monthly rain	100.3 mm (3.9 in)	30.4 mm (1.2 in)	37 years	50 of 100 (Notable)
21 July 1977	Eureka, US	daily rain	32.0 mm (1.3 in)	24.9 mm (1.0 in)	43 years	50 of 100 (Notable)
21 July 1977	Hartford Wwtp, US	daily rain	65.8 mm (2.6 in)	46.5 mm (1.8 in)	12 years	50 of 100 (Notable)
21 July 1977	Camargo (Smn), MX	daily rain	30.0 mm (1.2 in)	22.9 mm (0.9 in)	71 years	48 of 100 (Notable)
21 July 1977	Blanding, US	daily rain	26.7 mm (1.1 in)	20.9 mm (0.8 in)	4 years	44 of 100 (Notable)
21 July 1977	Waterdale, US	daily rain	51.8 mm (2.0 in)	15.0 mm (0.6 in)	56 years	43 of 100 (Notable)
21 July 1977	Darlington, US	monthly high max	42.2 C (108.0 F)	0.5 C (0.9 F)	75 years	41 of 100 (Notable)
21 July 1977	Newark Liberty Intl AP, US	daily high max	38.9 C (102.0 F)	1.7 C (3.1 F)	91 years	41 of 100 (Notable)
21 July 1977	Bluff City 3 SW, US	daily rain	82.0 mm (3.2 in)	59.6 mm (2.3 in)	24 years	40 of 100 (Notable)
21 July 1977	Helvecia (Efbm), BR	daily rain	58.4 mm (2.3 in)	27.5 mm (1.1 in)	11 years	39 of 100 (Notable)
21 July 1977	Huntington, US	daily rain	50.3 mm (2.0 in)	21.9 mm (0.9 in)	48 years	39 of 100 (Notable)
21 July 1977	Rockport 1 ESE, US	daily high min	25.0 C (77.0 F)	4.4 C (7.9 F)	54 years	39 of 100 (Notable)
21 July 1977	Penn Yan, US	daily high min	25.6 C (78.1 F)	3.4 C (6.1 F)	76 years	39 of 100 (Notable)
21 July 1977	Coldwater St School, US	daily rain	33.3 mm (1.3 in)	10.4 mm (0.4 in)	74 years	38 of 100 (Notable)
21 July 1977	Ewing, US	daily rain	49.0 mm (1.9 in)	26.1 mm (1.0 in)	36 years	38 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

1794 to 1977

Records set or tied on this calendar date in each year from 1794 to 1977. 1977 had 708 records.

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

Records on 07-21 in each year
Year	Records
1794	1
1795	1
1796	1
1797	1
1813	2
1832	2
1837	1
1839	1
1843	1
1844	2
1854	1
1859	3
1865	3
1868	3
1872	1
1876	1
1879	2
1880	1
1881	1
1884	1
1885	1
1886	2
1888	2
1889	3
1890	2
1892	3
1893	3
1894	3
1895	1
1896	3
1897	4
1898	7
1899	2
1900	6
1901	13
1902	12
1903	10
1904	8
1905	13
1906	13
1907	12
1908	25
1909	18
1910	12
1911	37
1912	52
1913	41
1914	48
1915	81
1916	72
1917	136
1918	130
1919	51
1920	33
1921	55
1922	48
1923	132
1924	286
1925	202
1926	401
1927	191
1928	205
1929	360
1930	521
1931	549
1932	322
1933	208
1934	965
1935	236
1936	322
1937	253
1938	638
1939	415
1940	318
1941	226
1942	318
1943	253
1944	716
1945	300
1946	398
1947	795
1948	403
1949	603
1950	662
1951	427
1952	657
1953	351
1954	656
1955	582
1956	490
1957	447
1958	531
1959	940
1960	651
1961	388
1962	263
1963	470
1964	457
1965	748
1966	626
1967	313
1968	334
1969	636
1970	1,241
1971	475
1972	1,046
1973	871
1974	536
1975	380
1976	477
1977	708
1978	1,155
1979	964
1980	926
1981	1,352
1982	588
1983	1,234
1984	764
1985	554
1986	791
1987	1,025
1988	1,015
1989	973
1990	914
1991	812
1992	1,562
1993	866
1994	773
1995	1,247
1996	1,141
1997	849
1998	1,674
1999	814
2000	1,230
2001	889
2002	990
2003	1,250
2004	694
2005	1,420
2006	1,479
2007	1,145
2008	989
2009	1,306
2010	1,148
2011	1,414
2012	815
2013	526
2014	762
2015	704
2016	645
2017	433
2018	942
2019	755
2020	363
2021	574
2022	866
2023	816
2024	873
2025	881
2026	874

Download the Data

Data for records on 1977-07-21: 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 2026-10-14 (14 October 2026). Records are computed by this site and are not official.

Data as of 2026-10-12. Last revised 12 October 2026 (2026-10-12).

Margin	Records
0 to 10	448
10 to 20	41
20 to 30	14
30 to 40	2
40 to 50	2
50 to 60	1