Daily records
Page built 2026-10-19
Data as of 2025-12-31
Search
Built 2026-10-19 (19 October 2026)

Mason City Threshold Days by Year (USC00255250)

17 fixed thresholds counted per year at Mason City (USC00255250): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Mason City Thresholds

  • Mason City: days with 10 mm (0.39 in) or more of precipitation in 87 years, most in 1915 with 38.
  • Mason City: days with 25 mm (0.98 in) or more of precipitation in 87 years, most in 2008 with 14.
  • Mason City: days with 10 cm (3.9 in) or more of snowfall in 54 years, most in 1944 with 6.
  • Mason City: days with 50 mm (1.97 in) or more of precipitation in 50 years, most in 1915 with 5.
  • 17 fixed thresholds have at least one qualifying day at Mason City.
35 years with a qualifying day
Days at or above 30 C (86 F) per year at Mason City Days per year at Mason City with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 85 in 1900. 02550751001896: 661897: 701898: 721899: 681900: 851901: 711902: 711903: 501904: 411987: 541988: 731989: 421990: 551991: 621992: 271993: 261994: 551995: 531996: 341997: 491998: 581999: 442000: 732001: 672002: 772003: 662004: 462005: 772006: 762007: 552008: 392009: 242013: 592014: 402015: 60189619001904199019941998200220062013
Days per year at Mason City with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 85 in 1900.
Days at or above 30 C (86 F) per year at Mason City
YearDaysDecade average
18966669
18977069
18987269
18996869
19008563.6
19017163.6
19027163.6
19035063.6
19044163.6
19875456.3
19887356.3
19894256.3
19905546.3
19916246.3
19922746.3
19932646.3
19945546.3
19955346.3
19963446.3
19974946.3
19985846.3
19994446.3
20007360
20016760
20027760
20036660
20044660
20057760
20067660
20075560
20083960
20092460
20135953
20144053
20156053
First to last qualifying date each year at Mason City For each year, a bar from the first to the last day at Mason City meeting 30 C (86 F). 1896: 5 May 1896 to 1 October 18961897: 19 May 1897 to 7 October 18971898: 16 April 1898 to 27 September 18981899: 12 April 1899 to 21 October 18991900: 11 May 1900 to 3 October 19001901: 25 April 1901 to 24 September 19011902: 20 April 1902 to 20 October 19021903: 16 June 1903 to 3 October 19031904: 22 May 1904 to 2 October 19041987: 20 April 1987 to 5 October 19871988: 8 April 1988 to 27 September 19881989: 11 March 1989 to 14 October 19891990: 23 April 1990 to 6 October 19901991: 6 April 1991 to 23 October 19911992: 30 April 1992 to 4 October 19921993: 17 June 1993 to 6 October 19931994: 18 April 1994 to 30 September 19941995: 7 June 1995 to 17 October 19951996: 25 April 1996 to 14 October 19961997: 17 May 1997 to 3 October 19971998: 18 May 1998 to 29 September 19981999: 5 June 1999 to 26 September 19992000: 23 May 2000 to 1 October 20002001: 2 May 2001 to 3 October 20012002: 16 April 2002 to 1 October 20022003: 2 April 2003 to 23 October 20032004: 19 April 2004 to 21 September 20042005: 20 May 2005 to 19 October 20052006: 11 April 2006 to 8 October 20062007: 30 April 2007 to 7 October 20072008: 19 May 2008 to 27 September 20082009: 24 April 2009 to 25 August 20092013: 30 April 2013 to 27 September 20132014: 27 May 2014 to 9 September 20142015: 17 March 2015 to 12 October 20151896190119881993199820032008JanFebMarAprMayJunJulAugSepOctNovDec
For each year, a bar from the first to the last day at Mason City meeting 30 C (86 F).
First to last qualifying date each year at Mason City
YearFirst dateLast date
18961896-05-051896-10-01
18971897-05-191897-10-07
18981898-04-161898-09-27
18991899-04-121899-10-21
19001900-05-111900-10-03
19011901-04-251901-09-24
19021902-04-201902-10-20
19031903-06-161903-10-03
19041904-05-221904-10-02
19871987-04-201987-10-05
19881988-04-081988-09-27
19891989-03-111989-10-14
19901990-04-231990-10-06
19911991-04-061991-10-23
19921992-04-301992-10-04
19931993-06-171993-10-06
19941994-04-181994-09-30
19951995-06-071995-10-17
19961996-04-251996-10-14
19971997-05-171997-10-03
19981998-05-181998-09-29
19991999-06-051999-09-26
20002000-05-232000-10-01
20012001-05-022001-10-03
20022002-04-162002-10-01
20032003-04-022003-10-23
20042004-04-192004-09-21
20052005-05-202005-10-19
20062006-04-112006-10-08
20072007-04-302007-10-07
20082008-05-192008-09-27
20092009-04-242009-08-25
20132013-04-302013-09-27
20142014-05-272014-09-09
20152015-03-172015-10-12

Every Fixed Threshold

Fixed thresholds at Mason City
ThresholdYears with a qualifying dayMost days in a yearYearLatest year days
30 C (86 F): Days3585190060
35 C (95 F): Days3233200212
40 C (104 F): Days10420051
90 F (32.2 C): Days3562190032
100 F (37.8 C): Days231519011
0 C (32 F): Ice days (max3559199331
0 C (32 F): Frost days (min311861898146
-10 C (14 F): Days with min3175198946
-20 C (-4 F): Days with min302619967
-30 C (-22 F): Days with min6519965
20 C (68 F): Tropical nights (min302520025
10 mm (0.39 in): Days with 10 mm or more rain8738191518
25 mm (0.98 in): Days with 25 mm or more rain871420086
50 mm (1.97 in): Days with 50 mm or more rain50519151
100 mm (3.94 in): Days with 100 mm or more rain3119571
10 cm (3.9 in): Days with 10 cm or more snowfall54619442
25 cm (9.8 in): Days with 25 cm or more snowfall8119251

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1896.

Download the Data

  • Data for Mason City 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 (2025-12-31).