Built 2026-10-19 (19 October 2026)

Harrow Cda Threshold Days by Year (CA006133360)

16 fixed thresholds counted per year at Harrow Cda (CA006133360): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Harrow Cda Thresholds

  • Harrow Cda: days with a maximum temperature at or above 30 C (86 F) in 66 years, most in 1944 with 58.
  • Harrow Cda: days with a maximum temperature at or below 0 C (32 F) in 66 years, most in 1960 with 80.
  • Harrow Cda: nights with a minimum temperature at or below 0 C (32 F) in 66 years, most in 1926 with 163.
  • Harrow Cda: nights with a minimum temperature at or below -10 C (14 F) in 66 years, most in 1978 with 61.
  • 16 fixed thresholds have at least one qualifying day at Harrow Cda.
66 years with a qualifying day
Days at or above 30 C (86 F) per year at Harrow Cda Days per year at Harrow Cda with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 58 in 1944. 02040601918: 351919: 391920: 151921: 431922: 251923: 261924: 191925: 311926: 191927: 141928: 231929: 221930: 331931: 391932: 221933: 491934: 461935: 231936: 451937: 261938: 321939: 301940: 191941: 401942: 251943: 341944: 581945: 271946: 401947: 351948: 301949: 411950: 281951: 271952: 461953: 401954: 271955: 421956: 81957: 91958: 21959: 191960: 101961: 121962: 161963: 191964: 311965: 131966: 171967: 111968: 161969: 101970: 141971: 111972: 91973: 171974: 141975: 131976: 131977: 131978: 171979: 41980: 131981: 81982: 71983: 291918192519321939194619531960196719741981
Days per year at Harrow Cda with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 58 in 1944.
Days at or above 30 C (86 F) per year at Harrow Cda
YearDaysDecade average
19183537
19193937
19201523.7
19214323.7
19222523.7
19232623.7
19241923.7
19253123.7
19261923.7
19271423.7
19282323.7
19292223.7
19303334.5
19313934.5
19322234.5
19334934.5
19344634.5
19352334.5
19364534.5
19372634.5
19383234.5
19393034.5
19401934.9
19414034.9
19422534.9
19433434.9
19445834.9
19452734.9
19464034.9
19473534.9
19483034.9
19494134.9
19502824.8
19512724.8
19524624.8
19534024.8
19542724.8
19554224.8
1956824.8
1957924.8
1958224.8
19591924.8
19601015.5
19611215.5
19621615.5
19631915.5
19643115.5
19651315.5
19661715.5
19671115.5
19681615.5
19691015.5
19701412.5
19711112.5
1972912.5
19731712.5
19741412.5
19751312.5
19761312.5
19771312.5
19781712.5
1979412.5
19801314.3
1981814.3
1982714.3
19832914.3
First to last qualifying date each year at Harrow Cda For each year, a bar from the first to the last day at Harrow Cda meeting 30 C (86 F). 1918: 22 May 1918 to 27 August 19181919: 2 June 1919 to 10 September 19191920: 10 June 1920 to 26 September 19201921: 22 May 1921 to 11 September 19211922: 7 June 1922 to 10 September 19221923: 1 June 1923 to 3 September 19231924: 20 June 1924 to 31 August 19241925: 23 May 1925 to 11 September 19251926: 7 May 1926 to 16 August 19261927: 25 June 1927 to 17 September 19271928: 7 July 1928 to 11 September 19281929: 29 May 1929 to 4 September 19291930: 10 April 1930 to 14 September 19301931: 29 May 1931 to 21 September 19311932: 25 May 1932 to 19 September 19321933: 24 May 1933 to 8 September 19331934: 19 May 1934 to 19 August 19341935: 4 July 1935 to 18 September 19351936: 9 May 1936 to 23 September 19361937: 31 May 1937 to 4 September 19371938: 22 June 1938 to 4 September 19381939: 31 May 1939 to 8 October 19391940: 7 June 1940 to 20 September 19401941: 5 May 1941 to 16 September 19411942: 30 April 1942 to 15 September 19421943: 4 June 1943 to 2 September 19431944: 26 May 1944 to 5 September 19441945: 23 June 1945 to 8 September 19451946: 11 June 1946 to 6 October 19461947: 10 June 1947 to 19 September 19471948: 3 June 1948 to 19 September 19481949: 4 May 1949 to 27 August 19491950: 7 June 1950 to 28 August 19501951: 15 May 1951 to 5 October 19511952: 5 May 1952 to 1 October 19521953: 4 June 1953 to 4 September 19531954: 9 June 1954 to 5 September 19541955: 3 May 1955 to 19 September 19551956: 10 June 1956 to 27 July 19561957: 16 June 1957 to 9 August 19571958: 2 July 1958 to 10 July 19581959: 8 June 1959 to 9 September 19591960: 4 June 1960 to 8 September 19601961: 12 June 1961 to 13 September 19611962: 14 May 1962 to 4 August 19621963: 9 May 1963 to 19 September 19631964: 22 May 1964 to 10 September 19641965: 6 June 1965 to 15 August 19651966: 27 May 1966 to 2 September 19661967: 27 May 1967 to 24 July 19671968: 7 June 1968 to 24 August 19681969: 29 May 1969 to 31 August 19691970: 22 May 1970 to 21 September 19701971: 19 June 1971 to 8 September 19711972: 14 June 1972 to 23 July 19721973: 10 June 1973 to 4 September 19731974: 3 July 1974 to 20 August 19741975: 19 May 1975 to 2 August 19751976: 8 June 1976 to 8 September 19761977: 13 May 1977 to 20 July 19771978: 27 June 1978 to 20 September 19781979: 15 June 1979 to 7 August 19791980: 5 May 1980 to 8 August 19801981: 15 June 1981 to 18 July 19811982: 7 July 1982 to 13 September 19821983: 12 June 1983 to 10 September 198319181927193619451954196319721981JanFebMarAprMayJunJulAugSepOctNovDec
For each year, a bar from the first to the last day at Harrow Cda meeting 30 C (86 F).
First to last qualifying date each year at Harrow Cda
YearFirst dateLast date
19181918-05-221918-08-27
19191919-06-021919-09-10
19201920-06-101920-09-26
19211921-05-221921-09-11
19221922-06-071922-09-10
19231923-06-011923-09-03
19241924-06-201924-08-31
19251925-05-231925-09-11
19261926-05-071926-08-16
19271927-06-251927-09-17
19281928-07-071928-09-11
19291929-05-291929-09-04
19301930-04-101930-09-14
19311931-05-291931-09-21
19321932-05-251932-09-19
19331933-05-241933-09-08
19341934-05-191934-08-19
19351935-07-041935-09-18
19361936-05-091936-09-23
19371937-05-311937-09-04
19381938-06-221938-09-04
19391939-05-311939-10-08
19401940-06-071940-09-20
19411941-05-051941-09-16
19421942-04-301942-09-15
19431943-06-041943-09-02
19441944-05-261944-09-05
19451945-06-231945-09-08
19461946-06-111946-10-06
19471947-06-101947-09-19
19481948-06-031948-09-19
19491949-05-041949-08-27
19501950-06-071950-08-28
19511951-05-151951-10-05
19521952-05-051952-10-01
19531953-06-041953-09-04
19541954-06-091954-09-05
19551955-05-031955-09-19
19561956-06-101956-07-27
19571957-06-161957-08-09
19581958-07-021958-07-10
19591959-06-081959-09-09
19601960-06-041960-09-08
19611961-06-121961-09-13
19621962-05-141962-08-04
19631963-05-091963-09-19
19641964-05-221964-09-10
19651965-06-061965-08-15
19661966-05-271966-09-02
19671967-05-271967-07-24
19681968-06-071968-08-24
19691969-05-291969-08-31
19701970-05-221970-09-21
19711971-06-191971-09-08
19721972-06-141972-07-23
19731973-06-101973-09-04
19741974-07-031974-08-20
19751975-05-191975-08-02
19761976-06-081976-09-08
19771977-05-131977-07-20
19781978-06-271978-09-20
19791979-06-151979-08-07
19801980-05-051980-08-08
19811981-06-151981-07-18
19821982-07-071982-09-13
19831983-06-121983-09-10

Every Fixed Threshold

Fixed thresholds at Harrow Cda
ThresholdYears with a qualifying dayMost days in a yearYearLatest year days
30 C (86 F): Days6658194429
35 C (95 F): Days311019362
40 C (104 F): Days2119181
90 F (32.2 C): Days623819446
100 F (37.8 C): Days3419361
0 C (32 F): Ice days (max6680196048
0 C (32 F): Frost days (min661631926123
-10 C (14 F): Days with min6661197822
-20 C (-4 F): Days with min411019184
20 C (68 F): Tropical nights (min6640192138
25 C (77 F): Days with min9219421
10 mm (0.39 in): Days with 10 mm or more rain6541195733
25 mm (0.98 in): Days with 25 mm or more rain621219817
50 mm (1.97 in): Days with 50 mm or more rain18219621
10 cm (3.9 in): Days with 10 cm or more snowfall57519211
25 cm (9.8 in): Days with 25 cm or more snowfall9319823

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1918.

Download the Data

  • Data for Harrow Cda threshold days by year: CSV or JSON. Field meanings are on the data page.

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 (17 October 2026). Threshold counts are computed by this site.

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