Built 2026-10-17 (17 October 2026)

Des Moines Wsfo-Johnston Weather Records (USC00132209)

Record envelope, standing records and threshold days for Des Moines Wsfo-Johnston (USC00132209), Iowa, United States, with 32 years of record.

Key Facts for Des Moines Wsfo-Johnston

  • Des Moines Wsfo-Johnston (USC00132209) is a weather station in Iowa, United States at 41.74 latitude and -93.72 longitude, 292 m (959 ft) above sea level.
  • The station reports from 1995 to 2026, 32 years of record.
  • 1,464 records set at Des Moines Wsfo-Johnston still stand.
  • Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
  • Des Moines Wsfo-Johnston set a daily record high maximum temperature of 31.1 C (88.0 F) on 12 October 2026 (provisional).

Provisional Records

Records set in the last 60 days are provisional until they clear the revision window.

About the Station

  • Location: Iowa, United States, 41.74 latitude, -93.72 longitude.
  • Elevation: 292 m (959 ft).
  • Period of record: 1995 to 2026, 32 years.
  • Eligible elements: tmax, tmin, prcp, snow, snwd.

Daily Record Envelope and 2026

27 days at or beyond a record
Daily record high and record low at Des Moines Wsfo-Johnston, with 2026 drawn through them The band shows the record high and record low for each calendar day at Des Moines Wsfo-Johnston. The lines show the 2026 daily maximum and minimum. 27 days in 2026 matched or passed a record. Temperatures are in degrees Celsius. -40-2002040 JanFebMarAprMayJunJulAugSepOctNovDec
The band shows the record high and record low for each calendar day at Des Moines Wsfo-Johnston. The lines show the 2026 daily maximum and minimum. 27 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.
Daily record high and record low at Des Moines Wsfo-Johnston, with 2026 drawn through them
MonthHighest record highLowest record low2026 highest maximum2026 lowest minimum
Jan19.4 C (66.9 F)-30.6 C (-23.1 F)16.7 C (62.1 F)-24.4 C (-11.9 F)
Feb25.0 C (77.0 F)-32.8 C (-27.0 F)20.0 C (68.0 F)-18.9 C (-2.0 F)
Mar33.3 C (91.9 F)-24.4 C (-11.9 F)33.3 C (91.9 F)-14.4 C (6.1 F)
Apr31.7 C (89.1 F)-10.6 C (12.9 F)31.1 C (88.0 F)-0.6 C (30.9 F)
May35.6 C (96.1 F)-2.2 C (28.0 F)31.1 C (88.0 F)1.1 C (34.0 F)
Jun37.8 C (100.0 F)5.0 C (41.0 F)32.8 C (91.0 F)11.1 C (52.0 F)
Jul40.0 C (104.0 F)9.4 C (48.9 F)36.7 C (98.1 F)14.4 C (57.9 F)
Aug39.4 C (102.9 F)7.8 C (46.0 F)33.9 C (93.0 F)13.9 C (57.0 F)
Sep38.3 C (100.9 F)-1.1 C (30.0 F)35.0 C (95.0 F)10.6 C (51.1 F)
Oct33.9 C (93.0 F)-8.9 C (16.0 F)31.1 C (88.0 F)7.2 C (45.0 F)
Nov27.2 C (81.0 F)-19.4 C (-2.9 F)n/an/a
Dec22.8 C (73.0 F)-28.3 C (-18.9 F)n/an/a

Which Years Hold Standing Records

1,464 standing records
Standing records at Des Moines Wsfo-Johnston by the year they were set 1,464 records at Des Moines Wsfo-Johnston still stand. 2000 holds the most, with 74. 0204060801995: 101996: 691997: 551998: 531999: 452000: 742001: 542002: 402003: 462004: 552005: 512006: 502007: 342008: 362009: 492010: 322011: 382012: 742013: 492014: 512015: 422016: 302017: 492018: 452019: 402020: 372021: 472022: 482023: 432024: 452025: 332026: 4019951999200320072011201520192023
1,464 records at Des Moines Wsfo-Johnston still stand. 2000 holds the most, with 74.
Standing records at Des Moines Wsfo-Johnston by the year they were set
Year setStanding records
199510
199669
199755
199853
199945
200074
200154
200240
200346
200455
200551
200650
200734
200836
200949
201032
201138
201274
201349
201451
201542
201630
201749
201845
201940
202037
202147
202248
202343
202445
202533
202640

Wettest Day of Each Month

Jul: 113.0 mm (4.4 in)
Record daily precipitation for each month at Des Moines Wsfo-Johnston The wettest day on record for each calendar month at Des Moines Wsfo-Johnston. The most was 113.0 mm (4.4 in) on 24 July 1997. 050100150 Jan: 33.5 mm (1.3 in), 2 January 2023 Jan Feb: 36.1 mm (1.4 in), 24 February 2007 Feb Mar: 48.5 mm (1.9 in), 30 March 1998 Mar Apr: 78.2 mm (3.1 in), 14 April 2012 Apr May: 85.1 mm (3.4 in), 21 May 2024 May Jun: 109.2 mm (4.3 in), 25 June 2005 Jun Jul: 113.0 mm (4.4 in), 24 July 1997 Jul Aug: 100.8 mm (4.0 in), 10 August 2010 Aug Sep: 92.5 mm (3.6 in), 25 September 2017 Sep Oct: 71.1 mm (2.8 in), 24 October 2021 Oct Nov: 90.2 mm (3.6 in), 3 November 2003 Nov Dec: 60.2 mm (2.4 in), 13 December 2015 Dec
The wettest day on record for each calendar month at Des Moines Wsfo-Johnston. The most was 113.0 mm (4.4 in) on 24 July 1997.
Record daily precipitation for each month at Des Moines Wsfo-Johnston
MonthRecord daily precipitation (mm)Date
Jan33.5 mm (1.3 in)2 January 2023
Feb36.1 mm (1.4 in)24 February 2007
Mar48.5 mm (1.9 in)30 March 1998
Apr78.2 mm (3.1 in)14 April 2012
May85.1 mm (3.4 in)21 May 2024
Jun109.2 mm (4.3 in)25 June 2005
Jul113.0 mm (4.4 in)24 July 1997
Aug100.8 mm (4.0 in)10 August 2010
Sep92.5 mm (3.6 in)25 September 2017
Oct71.1 mm (2.8 in)24 October 2021
Nov90.2 mm (3.6 in)3 November 2003
Dec60.2 mm (2.4 in)13 December 2015

Period of Record Coverage

1995 to 2026
Days with data per year at Des Moines Wsfo-Johnston 32 years of record at Des Moines Wsfo-Johnston, 1995 to 2026. 2 years have data for under 90 percent of days and are left out of rankings: 1995, 2026. 1995: 91 of 365 days1996: 362 of 366 days1997: 363 of 365 days1998: 364 of 365 days1999: 364 of 365 days2000: 363 of 366 days2001: 363 of 365 days2002: 364 of 365 days2003: 364 of 365 days2004: 364 of 366 days2005: 356 of 365 days2006: 362 of 365 days2007: 361 of 365 days2008: 365 of 366 days2009: 364 of 365 days2010: 365 of 365 days2011: 364 of 365 days2012: 335 of 366 days2013: 365 of 365 days2014: 364 of 365 days2015: 365 of 365 days2016: 366 of 366 days2017: 365 of 365 days2018: 363 of 365 days2019: 365 of 365 days2020: 362 of 366 days2021: 365 of 365 days2022: 365 of 365 days2023: 365 of 365 days2024: 366 of 366 days2025: 364 of 365 days2026: 280 of 365 days1995200020052010201520202025
32 years of record at Des Moines Wsfo-Johnston, 1995 to 2026. 2 years have data for under 90 percent of days and are left out of rankings: 1995, 2026.
Days with data per year at Des Moines Wsfo-Johnston
YearDays with dataShare of yearComplete
19959125%No
199636299%Yes
199736399%Yes
1998364100%Yes
1999364100%Yes
200036399%Yes
200136399%Yes
2002364100%Yes
2003364100%Yes
200436499%Yes
200535698%Yes
200636299%Yes
200736199%Yes
2008365100%Yes
2009364100%Yes
2010365100%Yes
2011364100%Yes
201233592%Yes
2013365100%Yes
2014364100%Yes
2015365100%Yes
2016366100%Yes
2017365100%Yes
201836399%Yes
2019365100%Yes
202036299%Yes
2021365100%Yes
2022365100%Yes
2023365100%Yes
2024366100%Yes
2025364100%Yes
202628077%No

Latest Records

20
Latest records at Des Moines Wsfo-Johnston
DateStationRecordValueBeat old record byOld record stoodSignificance
12 October 2026Des Moines Wsfo-Johnston, USdaily high max (Provisional)31.1 C (88.0 F)1.1 C (2.0 F)27 years12 of 100 (Routine)
11 October 2026Des Moines Wsfo-Johnston, USdaily high max (Provisional)31.1 C (88.0 F)1.1 C (2.0 F)1 year4 of 100 (Routine)
10 October 2026Des Moines Wsfo-Johnston, USdaily high min (Provisional)17.8 C (64.0 F)3.4 C (6.1 F)15 years13 of 100 (Routine)
10 October 2026Des Moines Wsfo-Johnston, USdaily high max (Provisional)30.0 C (86.0 F)1.1 C (2.0 F)1 year4 of 100 (Routine)
8 October 2026Des Moines Wsfo-Johnston, USdaily rain (Provisional)22.6 mm (0.9 in)2.0 mm (0.08 in)19 years9 of 100 (Routine)
30 September 2026Des Moines Wsfo-Johnston, USdaily rain (Provisional)21.8 mm (0.9 in)1.0 mm (0.04 in)4 years4 of 100 (Routine)
15 September 2026Des Moines Wsfo-Johnston, USdaily rain (Provisional)55.9 mm (2.2 in)24.1 mm (0.9 in)9 years23 of 100 (Routine)
14 September 2026Des Moines Wsfo-Johnston, USdaily rain (Provisional)20.8 mm (0.8 in)15.5 mm (0.6 in)7 years16 of 100 (Routine)
5 September 2026Des Moines Wsfo-Johnston, USdaily high min (Provisional)23.9 C (75.0 F)2.2 C (4.0 F)11 years10 of 100 (Routine)
4 September 2026Des Moines Wsfo-Johnston, USdaily high min (Provisional)23.3 C (73.9 F)1.1 C (2.0 F)12 years8 of 100 (Routine)
3 September 2026Des Moines Wsfo-Johnston, USdaily high min (Provisional)22.8 C (73.0 F)1.7 C (3.1 F)11 years9 of 100 (Routine)
2 September 2026Des Moines Wsfo-Johnston, USdaily high min (Provisional)23.3 C (73.9 F)2.2 C (4.0 F)25 years14 of 100 (Routine)
1 September 2026Des Moines Wsfo-Johnston, USdaily high max (Tie, Provisional)35.0 C (95.0 F)tie15 years1 of 100 (Routine)
31 August 2026Des Moines Wsfo-Johnston, USdaily high min (Provisional)23.3 C (73.9 F)2.7 C (4.9 F)25 years18 of 100 (Routine)
15 August 2026Des Moines Wsfo-Johnston, USdaily high min22.8 C (73.0 F)0.6 C (1.1 F)19 years9 of 100 (Routine)
14 August 2026Des Moines Wsfo-Johnston, USdaily rain30.0 mm (1.2 in)17.8 mm (0.7 in)1 year15 of 100 (Routine)
13 August 2026Des Moines Wsfo-Johnston, USdaily rain42.4 mm (1.7 in)28.2 mm (1.1 in)24 years29 of 100 (Routine)
9 August 2026Des Moines Wsfo-Johnston, USdaily high min (Tie)21.7 C (71.1 F)tie4 years1 of 100 (Routine)
5 August 2026Des Moines Wsfo-Johnston, USdaily low max20.6 C (69.1 F)2.7 C (4.9 F)21 years16 of 100 (Routine)
4 August 2026Des Moines Wsfo-Johnston, USdaily low max22.8 C (73.0 F)1.1 C (2.0 F)21 years12 of 100 (Routine)

Climate Trend

29 complete years, 1996 to 2025
Annual mean temperature at Des Moines Wsfo-Johnston as warming stripes, 1996 to 2025 One stripe for each of 29 complete years at Des Moines Wsfo-Johnston, 1996 to 2025. Blue stripes are years cooler than the station's own mean of 10.2 C (50.3 F); red stripes are warmer. The coolest year was 2014, at 8.1 C (46.6 F), and the warmest was 2024, at 11.9 C (53.5 F). The strongest colour marks a difference of 2.1 C (3.8 F). 1996: 8.2 C, -2.0 C from the station mean1997: 9.3 C, -0.9 C from the station mean1998: 11.3 C, +1.1 C from the station mean1999: 10.7 C, +0.5 C from the station mean2000: 10.2 C, 0.0 C from the station mean2001: 10.5 C, +0.3 C from the station mean2002: 10.6 C, +0.4 C from the station mean2003: 9.4 C, -0.8 C from the station mean2004: 9.6 C, -0.6 C from the station mean2005: 10.7 C, +0.5 C from the station mean2006: 11.5 C, +1.3 C from the station mean2007: 10.2 C, 0.0 C from the station mean2008: 8.5 C, -1.7 C from the station mean2009: 9.1 C, -1.1 C from the station mean2010: 9.6 C, -0.5 C from the station mean2011: 10.1 C, -0.1 C from the station mean2013: 9.3 C, -0.9 C from the station mean2014: 8.1 C, -2.1 C from the station mean2015: 10.2 C, 0.0 C from the station mean2016: 11.7 C, +1.5 C from the station mean2017: 11.3 C, +1.1 C from the station mean2018: 9.9 C, -0.3 C from the station mean2019: 9.4 C, -0.8 C from the station mean2020: 10.6 C, +0.4 C from the station mean2021: 11.2 C, +1.0 C from the station mean2022: 10.0 C, -0.2 C from the station mean2023: 11.4 C, +1.2 C from the station mean2024: 11.9 C, +1.7 C from the station mean2025: 11.0 C, +0.8 C from the station mean1996200020052010201520202025
One stripe for each of 29 complete years at Des Moines Wsfo-Johnston, 1996 to 2025. Blue stripes are years cooler than the station's own mean of 10.2 C (50.3 F); red stripes are warmer. The coolest year was 2014, at 8.1 C (46.6 F), and the warmest was 2024, at 11.9 C (53.5 F). The strongest colour marks a difference of 2.1 C (3.8 F).
Annual mean temperature at Des Moines Wsfo-Johnston as warming stripes, 1996 to 2025
YearAnnual mean temperatureDifference from the station mean
19968.2 C-2.04 C
19979.3 C-0.91 C
199811.3 C+1.08 C
199910.7 C+0.54 C
200010.2 C+0.03 C
200110.5 C+0.32 C
200210.6 C+0.38 C
20039.4 C-0.76 C
20049.6 C-0.58 C
200510.7 C+0.52 C
200611.5 C+1.30 C
200710.2 C+0.01 C
20088.5 C-1.73 C
20099.1 C-1.13 C
20109.6 C-0.55 C
201110.1 C-0.07 C
20139.3 C-0.86 C
20148.1 C-2.07 C
201510.2 C+0.01 C
201611.7 C+1.46 C
201711.3 C+1.14 C
20189.9 C-0.28 C
20199.4 C-0.77 C
202010.6 C+0.37 C
202111.2 C+1.03 C
202210.0 C-0.22 C
202311.4 C+1.17 C
202411.9 C+1.74 C
202511.0 C+0.79 C

This station does not have enough complete years (30 are needed) to fit a temperature trend.

A year is complete when all 12 months have at least 20 days of both daily maximum and daily minimum readings. The annual mean is the mean of the monthly means. The trend describes this one station over this period; it does not say what caused the change.

Extremes by Year

1995 to 2026
Yearly extremes at Des Moines Wsfo-Johnston: the record and the median year
MeasureRecordYear of the recordMedian yearYears with a value
Hottest day (TXx)40.0 C (104.0 F)201235.9 C (96.5 F)32
Coldest night (TNn)-32.8 C (-27.0 F)1996-25.6 C (-14.1 F)32
Wettest day (Rx1day)113.0 mm (4.4 in)199769.9 mm (2.8 in)32
Wettest five days (Rx5day)220.5 mm (8.7 in)2010109.8 mm (4.3 in)32
Longest dry spell (CDD)56 days200223 days32

Hottest day (TXx)

Hottest day (TXx) at Des Moines Wsfo-Johnston by year The hottest day of the year at Des Moines Wsfo-Johnston, 1995 to 2026. The record is 40.0 C (104.0 F) in 2012, marked on the chart; the median year is 35.9 C (96.5 F). 25303540200020102020Record: 40.0 C (104.0 F) in 2012
The hottest day of the year at Des Moines Wsfo-Johnston, 1995 to 2026. The record is 40.0 C (104.0 F) in 2012, marked on the chart; the median year is 35.9 C (96.5 F).
Hottest day (TXx) at Des Moines Wsfo-Johnston by year
YearHottest day (TXx)
199529.4 C (84.9 F)
199633.9 C (93.0 F)
199735.0 C (95.0 F)
199836.1 C (97.0 F)
199937.2 C (99.0 F)
200037.2 C (99.0 F)
200137.8 C (100.0 F)
200236.7 C (98.1 F)
200337.8 C (100.0 F)
200432.2 C (90.0 F)
200535.6 C (96.1 F)
200637.2 C (99.0 F)
200734.4 C (93.9 F)
200835.0 C (95.0 F)
200935.0 C (95.0 F)
201034.4 C (93.9 F)
201136.7 C (98.1 F)
201240.0 C (104.0 F)
201339.4 C (102.9 F)
201432.2 C (90.0 F)
201533.3 C (91.9 F)
201634.4 C (93.9 F)
201736.1 C (97.0 F)
201835.6 C (96.1 F)
201935.0 C (95.0 F)
202035.6 C (96.1 F)
202137.8 C (100.0 F)
202237.8 C (100.0 F)
202336.7 C (98.1 F)
202436.7 C (98.1 F)
202534.4 C (93.9 F)
202636.7 C (98.1 F)

Coldest night (TNn)

Coldest night (TNn) at Des Moines Wsfo-Johnston by year The coldest night of the year at Des Moines Wsfo-Johnston, 1995 to 2026. The record is -32.8 C (-27.0 F) in 1996, marked on the chart; the median year is -25.6 C (-14.1 F). -35-30-25-20-15200020102020Record: -32.8 C (-27.0 F) in 1996
The coldest night of the year at Des Moines Wsfo-Johnston, 1995 to 2026. The record is -32.8 C (-27.0 F) in 1996, marked on the chart; the median year is -25.6 C (-14.1 F).
Coldest night (TNn) at Des Moines Wsfo-Johnston by year
YearColdest night (TNn)
1995-21.7 C (-7.1 F)
1996-32.8 C (-27.0 F)
1997-26.1 C (-15.0 F)
1998-26.1 C (-15.0 F)
1999-26.7 C (-16.1 F)
2000-26.7 C (-16.1 F)
2001-23.9 C (-11.0 F)
2002-20.0 C (-4.0 F)
2003-23.9 C (-11.0 F)
2004-24.4 C (-11.9 F)
2005-25.0 C (-13.0 F)
2006-23.9 C (-11.0 F)
2007-25.0 C (-13.0 F)
2008-26.7 C (-16.1 F)
2009-30.6 C (-23.1 F)
2010-30.6 C (-23.1 F)
2011-25.6 C (-14.1 F)
2012-18.3 C (-0.9 F)
2013-25.6 C (-14.1 F)
2014-26.1 C (-15.0 F)
2015-24.4 C (-11.9 F)
2016-26.7 C (-16.1 F)
2017-28.3 C (-18.9 F)
2018-30.0 C (-22.0 F)
2019-30.0 C (-22.0 F)
2020-23.9 C (-11.0 F)
2021-28.9 C (-20.0 F)
2022-24.4 C (-11.9 F)
2023-20.6 C (-5.1 F)
2024-27.8 C (-18.0 F)
2025-25.6 C (-14.1 F)
2026-24.4 C (-11.9 F)

Wettest day (Rx1day)

Wettest day (Rx1day) at Des Moines Wsfo-Johnston by year The wettest day of the year at Des Moines Wsfo-Johnston, 1995 to 2026. The record is 113.0 mm (4.4 in) in 1997, marked on the chart; the median year is 69.9 mm (2.8 in). 0255075100125200020102020Record: 113.0 mm (4.4 in) in 1997
The wettest day of the year at Des Moines Wsfo-Johnston, 1995 to 2026. The record is 113.0 mm (4.4 in) in 1997, marked on the chart; the median year is 69.9 mm (2.8 in).
Wettest day (Rx1day) at Des Moines Wsfo-Johnston by year
YearWettest day (Rx1day)
199519.3 mm (0.8 in)
199655.1 mm (2.2 in)
1997113.0 mm (4.4 in)
199888.1 mm (3.5 in)
199959.7 mm (2.4 in)
200029.5 mm (1.2 in)
200141.9 mm (1.6 in)
200246.5 mm (1.8 in)
200390.2 mm (3.6 in)
200481.5 mm (3.2 in)
2005109.2 mm (4.3 in)
200651.8 mm (2.0 in)
200770.4 mm (2.8 in)
200882.8 mm (3.3 in)
200959.9 mm (2.4 in)
2010100.8 mm (4.0 in)
201182.3 mm (3.2 in)
201278.2 mm (3.1 in)
201356.1 mm (2.2 in)
201469.1 mm (2.7 in)
201583.1 mm (3.3 in)
201652.1 mm (2.1 in)
201792.5 mm (3.6 in)
201890.9 mm (3.6 in)
201962.2 mm (2.4 in)
202069.3 mm (2.7 in)
202171.1 mm (2.8 in)
202263.2 mm (2.5 in)
202356.6 mm (2.2 in)
202485.1 mm (3.4 in)
202556.9 mm (2.2 in)
202696.3 mm (3.8 in)

Wettest five days (Rx5day)

Wettest five days (Rx5day) at Des Moines Wsfo-Johnston by year The wettest five days of the year at Des Moines Wsfo-Johnston, 1995 to 2026. The record is 220.5 mm (8.7 in) in 2010, marked on the chart; the median year is 109.8 mm (4.3 in). 050100150200250200020102020Record: 220.5 mm (8.7 in) in 2010
The wettest five days of the year at Des Moines Wsfo-Johnston, 1995 to 2026. The record is 220.5 mm (8.7 in) in 2010, marked on the chart; the median year is 109.8 mm (4.3 in).
Wettest five days (Rx5day) at Des Moines Wsfo-Johnston by year
YearWettest five days (Rx5day)
199539.7 mm (1.6 in)
199674.9 mm (2.9 in)
1997135.3 mm (5.3 in)
1998120.3 mm (4.7 in)
199979.1 mm (3.1 in)
200051.6 mm (2.0 in)
200189.7 mm (3.5 in)
200283.6 mm (3.3 in)
2003119.4 mm (4.7 in)
2004119.3 mm (4.7 in)
2005125.9 mm (5.0 in)
200664.8 mm (2.6 in)
2007126.4 mm (5.0 in)
2008159.5 mm (6.3 in)
200981.3 mm (3.2 in)
2010220.5 mm (8.7 in)
201197.0 mm (3.8 in)
201296.9 mm (3.8 in)
2013106.2 mm (4.2 in)
2014160.8 mm (6.3 in)
2015110.2 mm (4.3 in)
2016109.9 mm (4.3 in)
201793.5 mm (3.7 in)
2018159.6 mm (6.3 in)
2019120.4 mm (4.7 in)
202090.5 mm (3.6 in)
2021117.4 mm (4.6 in)
202292.2 mm (3.6 in)
202399.0 mm (3.9 in)
2024109.7 mm (4.3 in)
2025110.7 mm (4.4 in)
2026128.4 mm (5.1 in)

Longest dry spell (CDD)

Longest dry spell (CDD) at Des Moines Wsfo-Johnston by year The longest dry spell of the year at Des Moines Wsfo-Johnston, 1995 to 2026. The record is 56 days in 2002, marked on the chart; the median year is 23 days. 0204060200020102020Record: 56 days in 2002
The longest dry spell of the year at Des Moines Wsfo-Johnston, 1995 to 2026. The record is 56 days in 2002, marked on the chart; the median year is 23 days.
Longest dry spell (CDD) at Des Moines Wsfo-Johnston by year
YearLongest dry spell (CDD)
199516 days
199623 days
199716 days
199823 days
199933 days
200018 days
200115 days
200256 days
200331 days
200419 days
200525 days
200618 days
200730 days
200813 days
200924 days
201016 days
201121 days
201221 days
201320 days
201422 days
201526 days
201624 days
201735 days
201823 days
201918 days
202020 days
202129 days
202225 days
202326 days
202426 days
202540 days
202641 days

Each chart shows one value per year; the dot marks the record year. TXx is the hottest daily maximum, TNn the coldest daily minimum, Rx1day and Rx5day the largest one-day and five-day rain totals, and CDD the longest run of days with less than 1 mm of rain. A year with missing days can understate an extreme.

Frost Dates and Growing Season

29 years with a frost

Across 29 years with a frost, the median last spring frost at Des Moines Wsfo-Johnston falls on 22 April and the median first autumn frost on 16 October, which leaves a median of 177 days between them.

Fitted over all years, the growing season changes by +2.6 days per decade at this station.

Frost dates and growing season at Des Moines Wsfo-Johnston
MeasureMedian, all yearsEarliest periodRecent period (1996 to 2025)Recent against earliestFitted trend
Last spring frost22 Apriln/a22 Apriln/a-0.8 days per decade
First autumn frost16 Octobern/a16 Octobern/a+1.8 days per decade
Growing days177 daysn/a177 daysn/a+2.6 days per decade

A frost day is a day with a daily minimum at or below 0 C (32 F). The last spring frost and the first autumn frost are the last and first such days of the cold season, and growing days are the days between them. A negative trend for the last spring frost means it comes earlier.

Rainfall Return Levels

30 years, 1996 to 2025

A day with at least 70.7 mm (2.8 in) of rain is expected about once in 2 years. A day with at least 121.2 mm (4.8 in) of rain is expected about once in 100 years.

Rainfall return levels at Des Moines Wsfo-Johnston: the daily rain expected about once in a given number of years
Expected about once inA day with at leastNote
2 years70.7 mm (2.8 in)
5 years88.9 mm (3.5 in)
10 years98.7 mm (3.9 in)
25 years109.1 mm (4.3 in)
50 years115.6 mm (4.6 in)Longer than the 30 years of record
100 years121.2 mm (4.8 in)Longer than the 30 years of record

The levels come from a generalised extreme value (GEV) distribution fitted by L-moments to the wettest-day total of each year, 30 years of values from 1996 to 2025.

A return level is an estimate. It is least reliable for the long periods, 50 and 100 years, and for any period longer than the record behind the fit, where the fit has to reach past the largest day actually observed. It is not a forecast.

The largest wettest-day totals in the fit: 113.0 mm (4.4 in) in 1997; 109.2 mm (4.3 in) in 2005; 100.8 mm (4.0 in) in 2010.

Download the Data

  • Data for Des Moines Wsfo-Johnston standing records by year: CSV or JSON. Field meanings are on the data page.
  • Data for Des Moines Wsfo-Johnston 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 2026-10-15 (15 October 2026). Records are computed by this site and are not official.

Data as of . Last revised (2026-10-15).