Built 2026-10-17 (17 October 2026)

Rathbun Dam Weather Records (USC00136910)

Record envelope, standing records and threshold days for Rathbun Dam (USC00136910), Iowa, United States, with 57 years of record.

Key Facts for Rathbun Dam

  • Rathbun Dam (USC00136910) is a weather station in Iowa, United States at 40.82 latitude and -92.90 longitude, 296 m (970 ft) above sea level.
  • The station reports from 1970 to 2026, 57 years of record.
  • 1,464 records set at Rathbun Dam still stand.
  • Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
  • Rathbun Dam set a daily record precipitation of 32.8 mm (1.3 in) on 30 September 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, 40.82 latitude, -92.90 longitude.
  • Elevation: 296 m (970 ft).
  • Period of record: 1970 to 2026, 57 years.
  • Eligible elements: tmax, tmin, prcp, snow, snwd.

Daily Record Envelope and 2026

19 days at or beyond a record
Daily record high and record low at Rathbun Dam, with 2026 drawn through them The band shows the record high and record low for each calendar day at Rathbun Dam. The lines show the 2026 daily maximum and minimum. 19 days in 2026 matched or passed a record. Temperatures are in degrees Celsius. -40-200204060 JanFebMarAprMayJunJulAugSepOctNovDec
The band shows the record high and record low for each calendar day at Rathbun Dam. The lines show the 2026 daily maximum and minimum. 19 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.
Daily record high and record low at Rathbun Dam, with 2026 drawn through them
MonthHighest record highLowest record low2026 highest maximum2026 lowest minimum
Jan19.4 C (66.9 F)-33.3 C (-27.9 F)17.8 C (64.0 F)-23.9 C (-11.0 F)
Feb24.4 C (75.9 F)-32.2 C (-26.0 F)21.7 C (71.1 F)-17.8 C (0.0 F)
Mar32.8 C (91.0 F)-23.9 C (-11.0 F)32.8 C (91.0 F)-14.4 C (6.1 F)
Apr31.7 C (89.1 F)-11.1 C (12.0 F)30.6 C (87.1 F)-0.6 C (30.9 F)
May36.1 C (97.0 F)-2.2 C (28.0 F)30.6 C (87.1 F)2.8 C (37.0 F)
Jun39.4 C (102.9 F)5.0 C (41.0 F)32.2 C (90.0 F)12.8 C (55.0 F)
Jul41.1 C (106.0 F)6.1 C (43.0 F)36.1 C (97.0 F)16.7 C (62.1 F)
Aug40.0 C (104.0 F)6.1 C (43.0 F)33.9 C (93.0 F)14.4 C (57.9 F)
Sep37.2 C (99.0 F)-1.1 C (30.0 F)36.1 C (97.0 F)10.6 C (51.1 F)
Oct33.3 C (91.9 F)-8.9 C (16.0 F)31.1 C (88.0 F)7.2 C (45.0 F)
Nov26.1 C (79.0 F)-22.2 C (-8.0 F)n/an/a
Dec23.3 C (73.9 F)-32.2 C (-26.0 F)n/an/a

Which Years Hold Standing Records

1,464 standing records
Standing records at Rathbun Dam by the year they were set 1,464 records at Rathbun Dam still stand. 2012 holds the most, with 50. 02040601970: 211971: 381972: 371973: 141974: 451975: 301976: 371977: 291978: 331979: 321980: 311981: 161982: 261983: 351984: 241985: 301986: 301987: 251988: 381989: 471990: 371991: 471992: 271993: 181994: 211995: 151996: 351997: 231998: 321999: 222000: 382001: 272002: 212003: 202004: 222005: 102006: 232007: 182008: 142009: 222010: 122011: 222012: 502013: 192014: 252015: 162016: 122017: 252018: 342019: 182020: 122021: 172022: 222023: 142024: 142025: 172026: 251970197619821988199420002006201220182024
1,464 records at Rathbun Dam still stand. 2012 holds the most, with 50.
Standing records at Rathbun Dam by the year they were set
Year setStanding records
197021
197138
197237
197314
197445
197530
197637
197729
197833
197932
198031
198116
198226
198335
198424
198530
198630
198725
198838
198947
199037
199147
199227
199318
199421
199515
199635
199723
199832
199922
200038
200127
200221
200320
200422
200510
200623
200718
200814
200922
201012
201122
201250
201319
201425
201516
201612
201725
201834
201918
202012
202117
202222
202314
202414
202517
202625

All-Time Record Progression

2 new records
When Rathbun Dam set new all-time records 2 all-time records were set at Rathbun Dam between 24 August 2007 and 24 July 2012. Each dot is a new record. Record daily precipitationRecord high maximum temperature24 August 2007: Record daily precipitation 313.4 mm (12.3 in)24 July 2012: Record high maximum temperature 41.1 C (106.0 F)2010
2 all-time records were set at Rathbun Dam between 24 August 2007 and 24 July 2012. Each dot is a new record.
When Rathbun Dam set new all-time records
DateKindDetail
2007-08-24Record daily precipitationRecord daily precipitation 313.4 mm (12.3 in)
2012-07-24Record high maximum temperatureRecord high maximum temperature 41.1 C (106.0 F)

Wettest Day of Each Month

Aug: 313.4 mm (12.3 in)
Record daily precipitation for each month at Rathbun Dam The wettest day on record for each calendar month at Rathbun Dam. The most was 313.4 mm (12.3 in) on 24 August 2007. 0100200300400 Jan: 33.8 mm (1.3 in), 31 January 2025 Jan Feb: 52.6 mm (2.1 in), 21 February 1997 Feb Mar: 56.4 mm (2.2 in), 6 March 2026 Mar Apr: 146.1 mm (5.8 in), 18 April 2013 Apr May: 77.5 mm (3.1 in), 14 May 1970 May Jun: 116.6 mm (4.6 in), 25 June 2015 Jun Jul: 175.0 mm (6.9 in), 5 July 2010 Jul Aug: 313.4 mm (12.3 in), 24 August 2007 Aug Sep: 114.3 mm (4.5 in), 7 September 2015 Sep Oct: 84.6 mm (3.3 in), 4 October 2013 Oct Nov: 63.5 mm (2.5 in), 2 November 1971 Nov Dec: 62.7 mm (2.5 in), 8 December 1980 Dec
The wettest day on record for each calendar month at Rathbun Dam. The most was 313.4 mm (12.3 in) on 24 August 2007.
Record daily precipitation for each month at Rathbun Dam
MonthRecord daily precipitation (mm)Date
Jan33.8 mm (1.3 in)31 January 2025
Feb52.6 mm (2.1 in)21 February 1997
Mar56.4 mm (2.2 in)6 March 2026
Apr146.1 mm (5.8 in)18 April 2013
May77.5 mm (3.1 in)14 May 1970
Jun116.6 mm (4.6 in)25 June 2015
Jul175.0 mm (6.9 in)5 July 2010
Aug313.4 mm (12.3 in)24 August 2007
Sep114.3 mm (4.5 in)7 September 2015
Oct84.6 mm (3.3 in)4 October 2013
Nov63.5 mm (2.5 in)2 November 1971
Dec62.7 mm (2.5 in)8 December 1980

Period of Record Coverage

1970 to 2026
Days with data per year at Rathbun Dam 57 years of record at Rathbun Dam, 1970 to 2026. 25 years have data for under 90 percent of days and are left out of rankings: 1970, 1973, 1997, 2004, 2005, 2006, 2007, 2008 and others. 1970: 215 of 365 days1971: 363 of 365 days1972: 335 of 366 days1973: 215 of 365 days1974: 364 of 365 days1975: 365 of 365 days1976: 366 of 366 days1977: 364 of 365 days1978: 364 of 365 days1979: 364 of 365 days1980: 363 of 366 days1981: 365 of 365 days1982: 358 of 365 days1983: 334 of 365 days1984: 365 of 366 days1985: 365 of 365 days1986: 365 of 365 days1987: 362 of 365 days1988: 355 of 366 days1989: 363 of 365 days1990: 365 of 365 days1991: 363 of 365 days1992: 363 of 366 days1993: 364 of 365 days1994: 365 of 365 days1995: 362 of 365 days1996: 346 of 366 days1997: 326 of 365 days1998: 337 of 365 days1999: 330 of 365 days2000: 330 of 366 days2001: 338 of 365 days2002: 353 of 365 days2003: 341 of 365 days2004: 320 of 366 days2005: 318 of 365 days2006: 317 of 365 days2007: 314 of 365 days2008: 316 of 366 days2009: 307 of 365 days2010: 302 of 365 days2011: 294 of 365 days2012: 258 of 366 days2013: 291 of 365 days2014: 290 of 365 days2015: 293 of 365 days2016: 300 of 366 days2017: 289 of 365 days2018: 287 of 365 days2019: 288 of 365 days2020: 283 of 366 days2021: 305 of 365 days2022: 311 of 365 days2023: 289 of 365 days2024: 314 of 366 days2025: 344 of 365 days2026: 253 of 365 days197019801990200020102020
57 years of record at Rathbun Dam, 1970 to 2026. 25 years have data for under 90 percent of days and are left out of rankings: 1970, 1973, 1997, 2004, 2005, 2006, 2007, 2008 and others.
Days with data per year at Rathbun Dam
YearDays with dataShare of yearComplete
197021559%No
197136399%Yes
197233592%Yes
197321559%No
1974364100%Yes
1975365100%Yes
1976366100%Yes
1977364100%Yes
1978364100%Yes
1979364100%Yes
198036399%Yes
1981365100%Yes
198235898%Yes
198333492%Yes
1984365100%Yes
1985365100%Yes
1986365100%Yes
198736299%Yes
198835597%Yes
198936399%Yes
1990365100%Yes
199136399%Yes
199236399%Yes
1993364100%Yes
1994365100%Yes
199536299%Yes
199634695%Yes
199732689%No
199833792%Yes
199933090%Yes
200033090%Yes
200133893%Yes
200235397%Yes
200334193%Yes
200432087%No
200531887%No
200631787%No
200731486%No
200831686%No
200930784%No
201030283%No
201129481%No
201225870%No
201329180%No
201429079%No
201529380%No
201630082%No
201728979%No
201828779%No
201928879%No
202028377%No
202130584%No
202231185%No
202328979%No
202431486%No
202534494%Yes
202625369%No

Latest Records

20
Latest records at Rathbun Dam
DateStationRecordValueBeat old record byOld record stoodSignificance
30 September 2026Rathbun Dam, USdaily rain (Provisional)32.8 mm (1.3 in)0.5 mm (0.02 in)40 years17 of 100 (Routine)
17 September 2026Rathbun Dam, USdaily high min (Provisional)20.0 C (68.0 F)0.6 C (1.1 F)33 years16 of 100 (Routine)
16 September 2026Rathbun Dam, USdaily high min (Provisional)20.0 C (68.0 F)0.6 C (1.1 F)0 years6 of 100 (Routine)
5 September 2026Rathbun Dam, USdaily high max (Provisional)35.6 C (96.1 F)0.6 C (1.1 F)36 years16 of 100 (Routine)
5 September 2026Rathbun Dam, USdaily high min (Tie, Provisional)22.2 C (72.0 F)tie8 years1 of 100 (Routine)
4 September 2026Rathbun Dam, USdaily high min (Provisional)23.9 C (75.0 F)2.8 C (5.0 F)55 years26 of 100 (Routine)
4 September 2026Rathbun Dam, USdaily high max (Provisional)35.6 C (96.1 F)1.7 C (3.1 F)43 years20 of 100 (Routine)
3 September 2026Rathbun Dam, USdaily high min (Tie, Provisional)22.8 C (73.0 F)tie25 years3 of 100 (Routine)
1 September 2026Rathbun Dam, USmonthly high min (Tie, Provisional)24.4 C (75.9 F)tie14 years4 of 100 (Routine)
15 August 2026Rathbun Dam, USdaily rain32.5 mm (1.3 in)4.6 mm (0.18 in)1 year7 of 100 (Routine)
12 August 2026Rathbun Dam, USdaily high min (Tie)23.9 C (75.0 F)tie4 years1 of 100 (Routine)
21 July 2026Rathbun Dam, USdaily rain33.5 mm (1.3 in)3.0 mm (0.12 in)29 years14 of 100 (Routine)
2 July 2026Rathbun Dam, USdaily high min23.9 C (75.0 F)0.6 C (1.1 F)7 years8 of 100 (Routine)
1 July 2026Rathbun Dam, USdaily high min (Tie)24.4 C (75.9 F)tie35 years3 of 100 (Routine)
30 June 2026Rathbun Dam, USmonthly high min (Tie)25.0 C (77.0 F)tie38 years6 of 100 (Routine)
27 June 2026Rathbun Dam, USdaily low max19.4 C (66.9 F)0.6 C (1.1 F)17 years11 of 100 (Routine)
22 June 2026Rathbun Dam, USdaily low max16.1 C (61.0 F)4.5 C (8.1 F)53 years32 of 100 (Routine)
10 June 2026Rathbun Dam, USdaily high min24.4 C (75.9 F)1.6 C (2.9 F)8 years11 of 100 (Routine)
9 June 2026Rathbun Dam, USdaily high min21.1 C (70.0 F)0.5 C (0.9 F)5 years7 of 100 (Routine)
18 May 2026Rathbun Dam, USdaily rain31.5 mm (1.2 in)12.7 mm (0.5 in)8 years16 of 100 (Routine)

Climate Trend

30 complete years, 1971 to 2025
Annual mean temperature at Rathbun Dam as warming stripes, 1971 to 2025 One stripe for each of 30 complete years at Rathbun Dam, 1971 to 2025. Blue stripes are years cooler than the station's own mean of 10.0 C (49.9 F); red stripes are warmer. The coolest year was 1978, at 8.3 C (47.0 F), and the warmest was 2024, at 12.2 C (53.9 F). The strongest colour marks a difference of 2.3 C (4.1 F). 1971: 9.8 C, -0.2 C from the station mean1974: 9.3 C, -0.6 C from the station mean1975: 9.9 C, -0.1 C from the station mean1976: 9.4 C, -0.6 C from the station mean1977: 10.0 C, +0.1 C from the station mean1978: 8.3 C, -1.6 C from the station mean1979: 8.4 C, -1.6 C from the station mean1980: 9.6 C, -0.3 C from the station mean1981: 10.5 C, +0.5 C from the station mean1982: 9.0 C, -1.0 C from the station mean1984: 9.7 C, -0.3 C from the station mean1985: 8.4 C, -1.6 C from the station mean1986: 10.3 C, +0.4 C from the station mean1987: 11.4 C, +1.5 C from the station mean1988: 10.2 C, +0.2 C from the station mean1989: 9.1 C, -0.9 C from the station mean1990: 11.0 C, +1.1 C from the station mean1991: 10.7 C, +0.7 C from the station mean1992: 10.2 C, +0.2 C from the station mean1993: 9.1 C, -0.9 C from the station mean1994: 10.0 C, +0.1 C from the station mean1995: 9.6 C, -0.3 C from the station mean1996: 8.7 C, -1.3 C from the station mean1999: 11.1 C, +1.1 C from the station mean2000: 10.5 C, +0.6 C from the station mean2002: 10.7 C, +0.8 C from the station mean2003: 10.1 C, +0.1 C from the station mean2022: 10.1 C, +0.1 C from the station mean2024: 12.2 C, +2.2 C from the station mean2025: 11.4 C, +1.5 C from the station mean197119751980198519901995200020052010201520202025
One stripe for each of 30 complete years at Rathbun Dam, 1971 to 2025. Blue stripes are years cooler than the station's own mean of 10.0 C (49.9 F); red stripes are warmer. The coolest year was 1978, at 8.3 C (47.0 F), and the warmest was 2024, at 12.2 C (53.9 F). The strongest colour marks a difference of 2.3 C (4.1 F).
Annual mean temperature at Rathbun Dam as warming stripes, 1971 to 2025
YearAnnual mean temperatureDifference from the station mean
19719.8 C-0.16 C
19749.3 C-0.62 C
19759.9 C-0.08 C
19769.4 C-0.55 C
197710.0 C+0.06 C
19788.3 C-1.63 C
19798.4 C-1.60 C
19809.6 C-0.34 C
198110.5 C+0.54 C
19829.0 C-0.96 C
19849.7 C-0.26 C
19858.4 C-1.56 C
198610.3 C+0.38 C
198711.4 C+1.48 C
198810.2 C+0.25 C
19899.1 C-0.86 C
199011.0 C+1.08 C
199110.7 C+0.75 C
199210.2 C+0.21 C
19939.1 C-0.90 C
199410.0 C+0.06 C
19959.6 C-0.34 C
19968.7 C-1.25 C
199911.1 C+1.13 C
200010.5 C+0.57 C
200210.7 C+0.78 C
200310.1 C+0.15 C
202210.1 C+0.12 C
202412.2 C+2.21 C
202511.4 C+1.46 C

The annual mean temperature here has risen by 0.4 C (0.2 to 0.6) per decade over 1971 to 2025. In Fahrenheit: 0.7 F (0.3 to 1.1) per decade. The slope is a straight line fitted to 30 complete years; the brackets give its 95 percent interval.

Fitted temperature trends per decade at Rathbun Dam
MeasurePer decade (C)Per decade (F)PeriodComplete yearsReading
Annual mean temperature0.4 C (0.2 to 0.6) per decade0.7 F (0.3 to 1.1) per decade1971 to 202530Rise
Mean daily maximum0.4 C (0.2 to 0.6) per decade0.7 F (0.3 to 1.2) per decade1971 to 202530Rise
Mean daily minimum0.3 C (0.1 to 0.6) per decade0.6 F (0.2 to 1.1) per decade1971 to 202530Rise

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

1970 to 2026
Yearly extremes at Rathbun Dam: the record and the median year
MeasureRecordYear of the recordMedian yearYears with a value
Hottest day (TXx)41.1 C (106.0 F)201236.1 C (97.0 F)57
Coldest night (TNn)-33.3 C (-27.9 F)1974-25.0 C (-13.0 F)57
Wettest day (Rx1day)313.4 mm (12.3 in)200763.5 mm (2.5 in)57
Wettest five days (Rx5day)397.5 mm (15.6 in)200798.5 mm (3.9 in)57
Longest dry spell (CDD)40 days198923 days57

Hottest day (TXx)

Hottest day (TXx) at Rathbun Dam by year The hottest day of the year at Rathbun Dam, 1970 to 2026. The record is 41.1 C (106.0 F) in 2012, marked on the chart; the median year is 36.1 C (97.0 F). 32.53537.54042.5197019801990200020102020Record: 41.1 C (106.0 F) in 2012
The hottest day of the year at Rathbun Dam, 1970 to 2026. The record is 41.1 C (106.0 F) in 2012, marked on the chart; the median year is 36.1 C (97.0 F).
Hottest day (TXx) at Rathbun Dam by year
YearHottest day (TXx)
197039.4 C (102.9 F)
197136.7 C (98.1 F)
197235.0 C (95.0 F)
197333.9 C (93.0 F)
197436.1 C (97.0 F)
197536.7 C (98.1 F)
197636.7 C (98.1 F)
197737.8 C (100.0 F)
197835.0 C (95.0 F)
197934.4 C (93.9 F)
198040.0 C (104.0 F)
198135.0 C (95.0 F)
198235.0 C (95.0 F)
198340.6 C (105.1 F)
198440.0 C (104.0 F)
198535.0 C (95.0 F)
198638.9 C (102.0 F)
198737.8 C (100.0 F)
198839.4 C (102.9 F)
198936.7 C (98.1 F)
199036.1 C (97.0 F)
199136.7 C (98.1 F)
199232.8 C (91.0 F)
199336.1 C (97.0 F)
199435.0 C (95.0 F)
199537.2 C (99.0 F)
199634.4 C (93.9 F)
199737.2 C (99.0 F)
199836.1 C (97.0 F)
199939.4 C (102.9 F)
200036.7 C (98.1 F)
200136.1 C (97.0 F)
200236.1 C (97.0 F)
200338.9 C (102.0 F)
200432.8 C (91.0 F)
200537.8 C (100.0 F)
200638.3 C (100.9 F)
200737.2 C (99.0 F)
200835.0 C (95.0 F)
200934.4 C (93.9 F)
201034.4 C (93.9 F)
201139.4 C (102.9 F)
201241.1 C (106.0 F)
201338.3 C (100.9 F)
201433.3 C (91.9 F)
201534.4 C (93.9 F)
201636.1 C (97.0 F)
201736.1 C (97.0 F)
201836.7 C (98.1 F)
201934.4 C (93.9 F)
202035.6 C (96.1 F)
202135.6 C (96.1 F)
202235.6 C (96.1 F)
202336.7 C (98.1 F)
202436.7 C (98.1 F)
202535.6 C (96.1 F)
202636.1 C (97.0 F)

Coldest night (TNn)

Coldest night (TNn) at Rathbun Dam by year The coldest night of the year at Rathbun Dam, 1970 to 2026. The record is -33.3 C (-27.9 F) in 1974, marked on the chart; the median year is -25.0 C (-13.0 F). -35-30-25-20-15197019801990200020102020Record: -33.3 C (-27.9 F) in 1974
The coldest night of the year at Rathbun Dam, 1970 to 2026. The record is -33.3 C (-27.9 F) in 1974, marked on the chart; the median year is -25.0 C (-13.0 F).
Coldest night (TNn) at Rathbun Dam by year
YearColdest night (TNn)
1970-15.6 C (3.9 F)
1971-30.0 C (-22.0 F)
1972-27.2 C (-17.0 F)
1973-23.9 C (-11.0 F)
1974-33.3 C (-27.9 F)
1975-27.2 C (-17.0 F)
1976-25.0 C (-13.0 F)
1977-28.9 C (-20.0 F)
1978-27.2 C (-17.0 F)
1979-31.1 C (-24.0 F)
1980-24.4 C (-11.9 F)
1981-26.7 C (-16.1 F)
1982-28.3 C (-18.9 F)
1983-28.3 C (-18.9 F)
1984-25.0 C (-13.0 F)
1985-29.4 C (-20.9 F)
1986-24.4 C (-11.9 F)
1987-21.1 C (-6.0 F)
1988-26.7 C (-16.1 F)
1989-32.2 C (-26.0 F)
1990-23.3 C (-9.9 F)
1991-22.2 C (-8.0 F)
1992-20.6 C (-5.1 F)
1993-21.1 C (-6.0 F)
1994-27.2 C (-17.0 F)
1995-22.8 C (-9.0 F)
1996-32.2 C (-26.0 F)
1997-25.6 C (-14.1 F)
1998-22.2 C (-8.0 F)
1999-29.4 C (-20.9 F)
2000-23.9 C (-11.0 F)
2001-26.7 C (-16.1 F)
2002-19.4 C (-2.9 F)
2003-21.7 C (-7.1 F)
2004-23.3 C (-9.9 F)
2005-21.7 C (-7.1 F)
2006-21.1 C (-6.0 F)
2007-22.2 C (-8.0 F)
2008-24.4 C (-11.9 F)
2009-26.1 C (-15.0 F)
2010-26.1 C (-15.0 F)
2011-23.3 C (-9.9 F)
2012-16.7 C (1.9 F)
2013-28.3 C (-18.9 F)
2014-26.7 C (-16.1 F)
2015-26.7 C (-16.1 F)
2016-23.3 C (-9.9 F)
2017-23.9 C (-11.0 F)
2018-28.9 C (-20.0 F)
2019-29.4 C (-20.9 F)
2020-25.0 C (-13.0 F)
2021-25.6 C (-14.1 F)
2022-24.4 C (-11.9 F)
2023-18.3 C (-0.9 F)
2024-28.9 C (-20.0 F)
2025-25.6 C (-14.1 F)
2026-23.9 C (-11.0 F)

Wettest day (Rx1day)

Wettest day (Rx1day) at Rathbun Dam by year The wettest day of the year at Rathbun Dam, 1970 to 2026. The record is 313.4 mm (12.3 in) in 2007, marked on the chart; the median year is 63.5 mm (2.5 in). 0100200300400197019801990200020102020Record: 313.4 mm (12.3 in) in 2007
The wettest day of the year at Rathbun Dam, 1970 to 2026. The record is 313.4 mm (12.3 in) in 2007, marked on the chart; the median year is 63.5 mm (2.5 in).
Wettest day (Rx1day) at Rathbun Dam by year
YearWettest day (Rx1day)
1970113.8 mm (4.5 in)
197163.5 mm (2.5 in)
197262.0 mm (2.4 in)
197361.0 mm (2.4 in)
197493.2 mm (3.7 in)
197546.7 mm (1.8 in)
197655.9 mm (2.2 in)
197773.7 mm (2.9 in)
197899.1 mm (3.9 in)
197932.8 mm (1.3 in)
1980127.8 mm (5.0 in)
1981104.4 mm (4.1 in)
1982124.5 mm (4.9 in)
198352.1 mm (2.1 in)
198466.0 mm (2.6 in)
198594.5 mm (3.7 in)
198672.4 mm (2.9 in)
198753.3 mm (2.1 in)
198848.3 mm (1.9 in)
198980.0 mm (3.1 in)
199081.0 mm (3.2 in)
199146.2 mm (1.8 in)
199297.5 mm (3.8 in)
199364.0 mm (2.5 in)
199458.4 mm (2.3 in)
199539.6 mm (1.6 in)
199650.8 mm (2.0 in)
199760.7 mm (2.4 in)
199894.2 mm (3.7 in)
199961.7 mm (2.4 in)
200063.5 mm (2.5 in)
200151.3 mm (2.0 in)
200248.0 mm (1.9 in)
200395.3 mm (3.8 in)
200468.6 mm (2.7 in)
200550.3 mm (2.0 in)
200640.4 mm (1.6 in)
2007313.4 mm (12.3 in)
200893.7 mm (3.7 in)
200969.9 mm (2.8 in)
2010175.0 mm (6.9 in)
201157.2 mm (2.3 in)
201231.5 mm (1.2 in)
2013146.1 mm (5.8 in)
201468.6 mm (2.7 in)
2015116.6 mm (4.6 in)
201647.0 mm (1.9 in)
201759.4 mm (2.3 in)
201846.0 mm (1.8 in)
201974.9 mm (2.9 in)
202043.7 mm (1.7 in)
202175.7 mm (3.0 in)
202253.6 mm (2.1 in)
202347.2 mm (1.9 in)
202467.8 mm (2.7 in)
202596.5 mm (3.8 in)
202656.4 mm (2.2 in)

Wettest five days (Rx5day)

Wettest five days (Rx5day) at Rathbun Dam by year The wettest five days of the year at Rathbun Dam, 1970 to 2026. The record is 397.5 mm (15.6 in) in 2007, marked on the chart; the median year is 98.5 mm (3.9 in). 0100200300400197019801990200020102020Record: 397.5 mm (15.6 in) in 2007
The wettest five days of the year at Rathbun Dam, 1970 to 2026. The record is 397.5 mm (15.6 in) in 2007, marked on the chart; the median year is 98.5 mm (3.9 in).
Wettest five days (Rx5day) at Rathbun Dam by year
YearWettest five days (Rx5day)
1970182.6 mm (7.2 in)
197184.6 mm (3.3 in)
197277.7 mm (3.1 in)
197385.7 mm (3.4 in)
197493.2 mm (3.7 in)
197567.3 mm (2.6 in)
197688.4 mm (3.5 in)
1977158.0 mm (6.2 in)
1978146.3 mm (5.8 in)
197965.7 mm (2.6 in)
1980205.5 mm (8.1 in)
1981126.8 mm (5.0 in)
1982184.9 mm (7.3 in)
198372.1 mm (2.8 in)
1984120.9 mm (4.8 in)
1985104.9 mm (4.1 in)
1986110.5 mm (4.4 in)
198797.3 mm (3.8 in)
198860.8 mm (2.4 in)
1989128.4 mm (5.1 in)
1990129.0 mm (5.1 in)
199175.6 mm (3.0 in)
1992135.8 mm (5.3 in)
1993149.7 mm (5.9 in)
199461.0 mm (2.4 in)
199580.0 mm (3.1 in)
1996113.8 mm (4.5 in)
199781.8 mm (3.2 in)
1998112.8 mm (4.4 in)
199969.4 mm (2.7 in)
200098.5 mm (3.9 in)
200177.9 mm (3.1 in)
200287.1 mm (3.4 in)
2003113.1 mm (4.5 in)
2004139.8 mm (5.5 in)
200573.1 mm (2.9 in)
200667.7 mm (2.7 in)
2007397.5 mm (15.6 in)
2008167.9 mm (6.6 in)
2009109.5 mm (4.3 in)
2010199.7 mm (7.9 in)
2011109.2 mm (4.3 in)
201252.1 mm (2.1 in)
2013156.6 mm (6.2 in)
2014105.9 mm (4.2 in)
2015166.3 mm (6.5 in)
201667.6 mm (2.7 in)
201769.1 mm (2.7 in)
201862.7 mm (2.5 in)
2019151.9 mm (6.0 in)
2020104.4 mm (4.1 in)
202192.0 mm (3.6 in)
202258.7 mm (2.3 in)
202353.8 mm (2.1 in)
202485.7 mm (3.4 in)
2025101.8 mm (4.0 in)
202698.4 mm (3.9 in)

Longest dry spell (CDD)

Longest dry spell (CDD) at Rathbun Dam by year The longest dry spell of the year at Rathbun Dam, 1970 to 2026. The record is 40 days in 1989, marked on the chart; the median year is 23 days. 010203040197019801990200020102020Record: 40 days in 1989
The longest dry spell of the year at Rathbun Dam, 1970 to 2026. The record is 40 days in 1989, marked on the chart; the median year is 23 days.
Longest dry spell (CDD) at Rathbun Dam by year
YearLongest dry spell (CDD)
197019 days
197130 days
197229 days
197314 days
197425 days
197524 days
197626 days
197721 days
197826 days
197926 days
198026 days
198131 days
198217 days
198325 days
198416 days
198526 days
198634 days
198728 days
198824 days
198940 days
199013 days
199123 days
199222 days
199324 days
199421 days
199523 days
199619 days
199714 days
199823 days
199937 days
200028 days
200135 days
200229 days
200315 days
200421 days
200526 days
200620 days
200724 days
200815 days
200925 days
201026 days
20115 days
201219 days
201331 days
201414 days
201513 days
201616 days
201723 days
201814 days
201913 days
202020 days
202117 days
202212 days
202314 days
202422 days
202530 days
202639 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

30 years with a frost

Across 30 years with a frost, the median last spring frost at Rathbun Dam falls on 18 April and the median first autumn frost on 10 October, which leaves a median of 179 days between them.

Fitted over all years, the growing season changes by +3.0 days per decade at this station.

Frost dates and growing season at Rathbun Dam
MeasureMedian, all yearsEarliest periodRecent period (1971 to 2025)Recent against earliestFitted trend
Last spring frost18 Apriln/a18 Apriln/a-0.6 days per decade
First autumn frost10 Octobern/a10 Octobern/a+2.4 days per decade
Growing days179 daysn/a179 daysn/a+3.0 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

34 years, 1972 to 2025

A day with at least 68.5 mm (2.7 in) of rain is expected about once in 2 years. A day with at least 145.4 mm (5.7 in) of rain is expected about once in 100 years.

Rainfall return levels at Rathbun Dam: the daily rain expected about once in a given number of years
Expected about once inA day with at leastNote
2 years68.5 mm (2.7 in)
5 years91.3 mm (3.6 in)
10 years105.5 mm (4.2 in)
25 years122.4 mm (4.8 in)
50 years134.2 mm (5.3 in)Longer than the 34 years of record
100 years145.4 mm (5.7 in)Longer than the 34 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, 34 years of values from 1972 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: 127.8 mm (5.0 in) in 1980; 124.5 mm (4.9 in) in 1982; 104.4 mm (4.1 in) in 1981.

Download the Data

  • Data for Rathbun Dam standing records by year: CSV or JSON. Field meanings are on the data page.
  • Data for Rathbun Dam 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).