Weather Records Against Chance: United States

In the 2020s, record highs ran at 1.43 times the number expected by chance in United States (1951-1980: 0.76) and record lows at 0.62 times (1951-1980: 0.87).

Data as of 2026-10-17. Last revised 17 October 2026 (2026-10-17).

Key Facts

In the 2020s so far (to 2026-10-17), 491,922 record highs of daily temperature were observed in United States against 343,801 expected by chance, 1.43 times the expected number. In 1951-1980 the same measure was 0.76.
In the 2020s so far (to 2026-10-17), 212,481 record lows of daily temperature were observed in United States against 343,801 expected by chance, 0.62 times the expected number. In 1951-1980 the same measure was 0.87.
By type in the 2020s in United States, observed over expected was 1.35 for record highs of the daily maximum, 0.72 for record lows of the daily maximum, 1.51 for record highs of the daily minimum, 0.51 for record lows of the daily minimum.
In 2026 (to 2026-10-17), record highs ran at 2.44 times the expected number in United States and record lows at 0.51 times.
Expected counts assume a stable climate: the k-th year of a station's record sets a record on a given day with chance 1 in k.
Readings are whole tenths of a degree and ties are not records, so strict records run below the naive expectation even without a trend. This page compares with the 1951-1980 level and not with 1.

How to Read This Page

In a stable climate, the k-th year of a station's record sets a record on a given day with chance 1 in k. Adding that chance up over every station, day and year gives the number of daily records expected without any change. The site records a station's records from its 31st year of data, so a station-year counts from there.

Readings are whole tenths of a degree, and a tie is not a record, so strict records run below the naive expectation even without a trend. For that reason the charts compare observed over expected with the 1951-1980 level (0.76 for record highs and 0.87 for record lows in this data), drawn as a dashed line, and not with 1.

Record highs and record lows combine the daily maximum and the daily minimum temperature. The level for each is the average of the two levels in the data. A value above the dashed line means more records than in 1951-1980; below it means fewer. The numbers show what was observed and how it compares. They do not say why.

Observed Over Expected by Year

Highs and lows

Record highs

Daily temperature record highs observed divided by the number expected by chance in United States, for each year from 1902 to 2026. Dashed line: the 1951-1980 level for record highs, 0.76.

Observed over expected record highs by year, United States
Year	record highs observed over expected
1902	0.62
1903	0.71
1904	0.48
1905	0.68
1906	0.81
1907	0.71
1908	0.97
1909	0.86
1910	0.94
1911	0.94
1912	0.59
1913	1.36
1914	0.95
1915	0.86
1916	0.88
1917	0.58
1918	1.15
1919	0.94
1920	0.64
1921	1.39
1922	0.98
1923	0.78
1924	0.77
1925	1.27
1926	0.74
1927	1.22
1928	0.98
1929	0.83
1930	1.52
1931	1.60
1932	1.02
1933	1.26
1934	1.57
1935	0.78
1936	1.54
1937	0.77
1938	1.05
1939	1.23
1940	0.75
1941	0.96
1942	0.72
1943	0.85
1944	0.75
1945	0.80
1946	0.93
1947	0.93
1948	0.78
1949	0.87
1950	0.90
1951	0.74
1952	0.83
1953	1.12
1954	1.12
1955	0.84
1956	0.85
1957	0.66
1958	0.72
1959	0.70
1960	0.59
1961	0.70
1962	0.80
1963	0.94
1964	0.67
1965	0.64
1966	0.67
1967	0.73
1968	0.64
1969	0.53
1970	0.66
1971	0.70
1972	0.78
1973	0.75
1974	0.81
1975	0.64
1976	0.71
1977	1.03
1978	0.60
1979	0.67
1980	1.05
1981	1.01
1982	0.75
1983	0.85
1984	0.91
1985	0.81
1986	1.12
1987	1.05
1988	1.13
1989	0.99
1990	1.27
1991	1.13
1992	0.79
1993	0.50
1994	0.77
1995	1.04
1996	0.96
1997	0.78
1998	1.39
1999	1.03
2000	1.21
2001	1.00
2002	1.13
2003	1.12
2004	0.80
2005	1.06
2006	1.18
2007	1.21
2008	0.77
2009	0.74
2010	0.99
2011	1.16
2012	1.65
2013	0.82
2014	0.79
2015	1.52
2016	1.29
2017	1.48
2018	1.10
2019	0.82
2020	1.30
2021	1.34
2022	1.22
2023	1.15
2024	1.35
2025	1.47
2026	2.44

Record lows

Daily temperature record lows observed divided by the number expected by chance in United States, for each year from 1902 to 2026. Dashed line: the 1951-1980 level for record lows, 0.87.

Observed over expected record lows by year, United States
Year	record lows observed over expected
1902	0.66
1903	1.07
1904	0.85
1905	0.61
1906	0.64
1907	0.94
1908	0.53
1909	0.79
1910	0.52
1911	0.68
1912	0.85
1913	0.70
1914	0.85
1915	0.70
1916	0.86
1917	1.40
1918	0.86
1919	0.72
1920	0.82
1921	0.40
1922	0.51
1923	0.79
1924	1.21
1925	0.93
1926	0.92
1927	0.81
1928	0.77
1929	1.00
1930	0.99
1931	0.50
1932	0.87
1933	0.67
1934	0.65
1935	0.86
1936	1.10
1937	0.83
1938	0.44
1939	0.48
1940	1.04
1941	0.40
1942	0.76
1943	0.87
1944	0.57
1945	0.78
1946	0.54
1947	0.72
1948	0.81
1949	0.71
1950	1.22
1951	1.12
1952	0.79
1953	0.55
1954	0.64
1955	0.95
1956	0.76
1957	0.66
1958	0.71
1959	0.73
1960	1.03
1961	0.78
1962	1.00
1963	0.94
1964	1.03
1965	1.06
1966	0.86
1967	1.03
1968	0.92
1969	0.72
1970	0.87
1971	0.96
1972	1.18
1973	0.63
1974	0.94
1975	0.88
1976	1.12
1977	0.80
1978	0.84
1979	0.99
1980	0.63
1981	0.60
1982	0.97
1983	1.22
1984	0.86
1985	1.21
1986	0.75
1987	0.66
1988	0.70
1989	1.42
1990	0.73
1991	0.86
1992	0.94
1993	0.97
1994	0.64
1995	0.71
1996	1.05
1997	0.85
1998	0.44
1999	0.54
2000	0.79
2001	0.46
2002	0.82
2003	0.57
2004	0.68
2005	0.48
2006	0.55
2007	0.60
2008	0.71
2009	0.87
2010	0.55
2011	0.66
2012	0.38
2013	0.95
2014	1.19
2015	0.67
2016	0.30
2017	0.59
2018	0.78
2019	0.96
2020	0.75
2021	0.66
2022	0.77
2023	0.62
2024	0.44
2025	0.56
2026	0.51

The charts start in 1902. 29 earlier years are left out because too few records were expected from the few stations with a long enough record. The data download has every year.

Observed and Expected Records by Year

Counts

Daily temperature records observed and expected by chance in United States for each year, highs and lows. Expected counts are the number a stable climate would give.

Observed and expected record highs and lows by year, United States
Year	Record highs observed	Record highs expected	Record lows observed	Record lows expected
1902	141	228	150	228
1903	223	315	339	315
1904	219	460	390	460
1905	344	504	308	504
1906	437	537	342	537
1907	367	520	488	520
1908	496	513	273	513
1909	508	592	467	592
1910	542	574	297	574
1911	548	581	398	581
1912	334	569	485	569
1913	744	546	383	546
1914	585	614	524	614
1915	635	739	517	739
1916	701	793	685	793
1917	496	848	1,191	848
1918	1,010	875	754	875
1919	869	925	669	925
1920	727	1,135	934	1,135
1921	1,987	1,433	575	1,433
1922	2,180	2,224	1,138	2,224
1923	6,974	8,926	7,088	8,926
1924	8,885	11,560	14,008	11,560
1925	16,599	13,024	12,140	13,024
1926	11,467	15,481	14,211	15,481
1927	21,073	17,254	13,999	17,254
1928	18,024	18,437	14,211	18,437
1929	16,203	19,563	19,572	19,563
1930	31,896	20,943	20,655	20,943
1931	36,010	22,443	11,178	22,443
1932	24,300	23,715	20,729	23,715
1933	30,828	24,563	16,501	24,563
1934	40,257	25,637	16,738	25,637
1935	21,294	27,374	23,481	27,374
1936	43,153	28,088	30,913	28,088
1937	22,434	29,149	24,286	29,149
1938	31,369	30,016	13,076	30,016
1939	37,507	30,570	14,727	30,570
1940	23,854	31,777	32,892	31,777
1941	30,733	32,086	12,785	32,086
1942	23,297	32,576	24,626	32,576
1943	27,819	32,910	28,792	32,910
1944	25,097	33,586	19,037	33,586
1945	27,570	34,285	26,906	34,285
1946	32,039	34,471	18,610	34,471
1947	31,933	34,276	24,667	34,276
1948	26,758	34,460	27,888	34,460
1949	30,218	34,726	24,633	34,726
1950	31,902	35,263	42,978	35,263
1951	26,127	35,334	39,523	35,334
1952	29,594	35,753	28,321	35,753
1953	40,150	35,974	19,938	35,974
1954	40,017	35,729	22,862	35,729
1955	30,176	36,035	34,182	36,035
1956	30,917	36,352	27,628	36,352
1957	23,786	36,092	23,741	36,092
1958	25,750	35,922	25,434	35,922
1959	25,434	36,133	26,547	36,133
1960	21,713	36,633	37,675	36,633
1961	25,672	36,631	28,393	36,631
1962	29,563	36,999	37,054	36,999
1963	34,357	36,585	34,461	36,585
1964	24,351	36,370	37,623	36,370
1965	23,419	36,349	38,376	36,349
1966	24,644	36,595	31,443	36,595
1967	27,071	37,207	38,247	37,207
1968	24,209	37,927	34,717	37,927
1969	20,413	38,741	27,984	38,741
1970	26,227	39,557	34,265	39,557
1971	28,355	40,537	38,726	40,537
1972	32,345	41,373	48,694	41,373
1973	30,402	40,302	25,564	40,302
1974	33,014	40,713	38,381	40,713
1975	26,246	40,822	36,008	40,822
1976	29,080	41,035	46,127	41,035
1977	41,963	40,670	32,668	40,670
1978	25,504	42,810	35,931	42,810
1979	29,847	44,740	44,452	44,740
1980	47,926	45,537	28,743	45,537
1981	46,763	46,200	27,609	46,200
1982	34,365	45,883	44,542	45,883
1983	39,169	46,270	56,636	46,270
1984	42,722	46,895	40,319	46,895
1985	37,657	46,617	56,334	46,617
1986	52,744	47,201	35,275	47,201
1987	50,137	47,821	31,486	47,821
1988	54,854	48,365	33,806	48,365
1989	48,726	49,057	69,793	49,057
1990	62,399	49,167	35,758	49,167
1991	56,287	49,900	42,906	49,900
1992	40,017	50,598	47,779	50,598
1993	25,496	50,830	49,382	50,830
1994	39,369	51,210	32,887	51,210
1995	53,450	51,259	36,163	51,259
1996	49,007	51,241	53,897	51,241
1997	39,615	50,739	43,014	50,739
1998	69,591	50,098	22,045	50,098
1999	50,917	49,566	26,950	49,566
2000	59,226	48,875	38,648	48,875
2001	48,253	48,338	22,228	48,338
2002	54,224	47,890	39,191	47,890
2003	53,242	47,368	27,215	47,368
2004	37,355	46,774	31,973	46,774
2005	48,487	45,627	21,719	45,627
2006	53,241	45,239	25,104	45,239
2007	54,034	44,743	26,955	44,743
2008	33,972	43,990	31,181	43,990
2009	31,942	42,962	37,264	42,962
2010	42,437	43,081	23,810	43,081
2011	48,936	42,315	27,952	42,315
2012	68,606	41,463	15,880	41,463
2013	32,848	40,258	38,107	40,258
2014	31,752	40,091	47,554	40,091
2015	62,387	41,025	27,296	41,025
2016	54,325	42,220	12,868	42,220
2017	64,720	43,740	26,002	43,740
2018	48,672	44,216	34,294	44,216
2019	38,669	46,955	45,153	46,955
2020	64,528	49,596	36,998	49,596
2021	68,142	50,975	33,415	50,975
2022	62,554	51,219	39,530	51,219
2023	58,956	51,380	32,096	51,380
2024	69,676	51,544	22,460	51,544
2025	75,270	51,084	28,581	51,084
2026	92,796	38,004	19,401	38,004

Observed Over Expected by Decade

Record highs

Decade values in United States: 1870s 0.96, 1880s 1.29, 1890s 1.21, 1900s 0.76, 1910s 0.92, 1920s 0.95, 1930s 1.22, 1940s 0.83, 1950s 0.85, 1960s 0.69, 1970s 0.73, 1980s 0.97, 1990s 0.96, 2000s 1.03, 2010s 1.16, 2020s 1.43. The 2020s run to 2026. Dashed line: the 1951-1980 level for record highs, 0.76.

Observed over expected record highs by decade, United States
Decade	record highs observed over expected
1870s	0.96
1880s	1.29
1890s	1.21
1900s	0.76
1910s	0.92
1920s	0.95
1930s	1.22
1940s	0.83
1950s	0.85
1960s	0.69
1970s	0.73
1980s	0.97
1990s	0.96
2000s	1.03
2010s	1.16
2020s	1.43

Record lows

Decade values in United States: 1870s 0.74, 1880s 0.80, 1890s 0.73, 1900s 0.74, 1910s 0.84, 1920s 0.90, 1930s 0.73, 1940s 0.72, 1950s 0.81, 1960s 0.93, 1970s 0.92, 1980s 0.90, 1990s 0.77, 2000s 0.65, 2010s 0.70, 2020s 0.62. The 2020s run to 2026. Dashed line: the 1951-1980 level for record lows, 0.87.

Observed over expected record lows by decade, United States
Decade	record lows observed over expected
1870s	0.74
1880s	0.80
1890s	0.73
1900s	0.74
1910s	0.84
1920s	0.90
1930s	0.73
1940s	0.72
1950s	0.81
1960s	0.93
1970s	0.92
1980s	0.90
1990s	0.77
2000s	0.65
2010s	0.70
2020s	0.62

Observed and expected daily temperature records by decade, United States
Decade	Highs observed	Highs expected	Highs observed over expected	Lows observed	Lows expected	Lows observed over expected
1870s	145	151	0.96	111	151	0.74
1880s	283	219	1.29	176	219	0.80
1890s	283	234	1.21	170	234	0.73
1900s	2,948	3,901	0.76	2,906	3,901	0.74
1910s	6,464	7,064	0.92	5,903	7,064	0.84
1920s	104,119	109,036	0.95	97,876	109,036	0.90
1930s	319,048	262,498	1.22	192,284	262,498	0.73
1940s	279,318	335,151	0.83	240,836	335,151	0.72
1950s	303,853	358,588	0.85	291,154	358,588	0.81
1960s	255,412	370,036	0.69	345,973	370,036	0.93
1970s	302,983	412,560	0.73	380,816	412,560	0.92
1980s	455,063	469,844	0.97	424,543	469,844	0.90
1990s	486,148	504,608	0.96	390,781	504,608	0.77
2000s	473,976	461,806	1.03	301,478	461,806	0.65
2010s	493,352	425,364	1.16	298,916	425,364	0.70
2020s	491,922	343,801	1.43	212,481	343,801	0.62

By Record Type, 2020s

Against the 1951-1980 level

Observed and expected records by type in the 2020s, United States, with the 1951-1980 level
Record type	Observed	Expected	Observed over expected	1951-1980 level
Record high maximum temperature	232,486	172,090	1.35	0.73
Record low maximum temperature	124,471	172,090	0.72	0.88
Record high minimum temperature	259,436	171,711	1.51	0.79
Record low minimum temperature	88,010	171,711	0.51	0.86

The 2020s are not over: this decade runs to 2026, up to 2026-10-17.

Download the Data

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 2026-10-17. Observed records are computed by this site from daily maximum and minimum temperature. Expected counts assume a stable climate.

Weather Records Against Chance: United States

Key Facts

How to Read This Page

Observed Over Expected by Year

Record highs

Record lows

Observed and Expected Records by Year

Observed Over Expected by Decade

Record highs

Record lows

By Record Type, 2020s

Download the Data

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