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Rapid City WFO Weather Records (USC00396948)

Record envelope, standing records and threshold days for Rapid City WFO (USC00396948), South Dakota, United States, with 31 years of record.

Key Facts for Rapid City WFO

  • Rapid City WFO (USC00396948) is a weather station in South Dakota, United States at 44.07 latitude and -103.21 longitude, 1,030 m (3,379 ft) above sea level.
  • The station reports from 1996 to 2026, 31 years of record.
  • 1,464 records set at Rapid City WFO still stand.
  • Records are tracked for tmax, tmin, prcp, snow, snwd: an element needs 30 years of data to be eligible.
  • Rapid City WFO set a daily record high maximum temperature of 32.2 C (90.0 F) on 10 October 2026 (provisional).

Provisional Records

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

About the Station

  • Location: South Dakota, United States, 44.07 latitude, -103.21 longitude.
  • Elevation: 1,030 m (3,379 ft).
  • Period of record: 1996 to 2026, 31 years.
  • Eligible elements: tmax, tmin, prcp, snow, snwd.

Daily Record Envelope and 2026

33 days at or beyond a record
Daily record high and record low at Rapid City WFO, with 2026 drawn through them The band shows the record high and record low for each calendar day at Rapid City WFO. The lines show the 2026 daily maximum and minimum. 33 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 Rapid City WFO. The lines show the 2026 daily maximum and minimum. 33 days in 2026 matched or passed a record. Temperatures are in degrees Celsius.
Daily record high and record low at Rapid City WFO, with 2026 drawn through them
MonthHighest record highLowest record low2026 highest maximum2026 lowest minimum
Jan22.8 C (73.0 F)-30.6 C (-23.1 F)16.7 C (62.1 F)-24.4 C (-11.9 F)
Feb22.8 C (73.0 F)-30.6 C (-23.1 F)20.6 C (69.1 F)-16.1 C (3.0 F)
Mar29.4 C (84.9 F)-26.7 C (-16.1 F)29.4 C (84.9 F)-12.8 C (9.0 F)
Apr32.8 C (91.0 F)-15.6 C (3.9 F)32.8 C (91.0 F)-4.4 C (24.1 F)
May35.0 C (95.0 F)-3.9 C (25.0 F)32.8 C (91.0 F)-0.6 C (30.9 F)
Jun41.1 C (106.0 F)-0.6 C (30.9 F)36.7 C (98.1 F)8.9 C (48.0 F)
Jul43.3 C (109.9 F)8.3 C (46.9 F)43.3 C (109.9 F)15.0 C (59.0 F)
Aug41.1 C (106.0 F)7.2 C (45.0 F)38.9 C (102.0 F)11.1 C (52.0 F)
Sep38.9 C (102.0 F)-1.7 C (28.9 F)35.0 C (95.0 F)8.9 C (48.0 F)
Oct34.4 C (93.9 F)-15.6 C (3.9 F)32.8 C (91.0 F)3.9 C (39.0 F)
Nov28.3 C (82.9 F)-22.2 C (-8.0 F)n/an/a
Dec23.3 C (73.9 F)-28.3 C (-18.9 F)n/an/a

Which Years Hold Standing Records

1,464 standing records
Standing records at Rapid City WFO by the year they were set 1,464 records at Rapid City WFO still stand. 1996 holds the most, with 93. 02550751001996: 931997: 461998: 391999: 532000: 592001: 402002: 492003: 542004: 422005: 682006: 542007: 432008: 412009: 452010: 342011: 422012: 502013: 402014: 542015: 352016: 472017: 482018: 402019: 412020: 562021: 552022: 342023: 312024: 362025: 532026: 4219962000200420082012201620202024
1,464 records at Rapid City WFO still stand. 1996 holds the most, with 93.
Standing records at Rapid City WFO by the year they were set
Year setStanding records
199693
199746
199839
199953
200059
200140
200249
200354
200442
200568
200654
200743
200841
200945
201034
201142
201250
201340
201454
201535
201647
201748
201840
201941
202056
202155
202234
202331
202436
202553
202642

All-Time Record Progression

1 new records
When Rapid City WFO set new all-time records 1 all-time records were set at Rapid City WFO between 25 July 2026 and 25 July 2026. Each dot is a new record. Record high maximum temperature25 July 2026: Record high maximum temperature 43.3 C (109.9 F)
1 all-time records were set at Rapid City WFO between 25 July 2026 and 25 July 2026. Each dot is a new record.
When Rapid City WFO set new all-time records
DateKindDetail
2026-07-25Record high maximum temperatureRecord high maximum temperature 43.3 C (109.9 F)

Wettest Day of Each Month

May: 77.0 mm (3.0 in)
Record daily precipitation for each month at Rapid City WFO The wettest day on record for each calendar month at Rapid City WFO. The most was 77.0 mm (3.0 in) on 22 May 2008. 020406080 Jan: 7.6 mm (0.30 in), 3 January 1996 Jan Feb: 18.0 mm (0.7 in), 3 February 1997 Feb Mar: 24.9 mm (1.0 in), 16 March 2018 Mar Apr: 40.6 mm (1.6 in), 6 April 2024 Apr May: 77.0 mm (3.0 in), 22 May 2008 May Jun: 59.2 mm (2.3 in), 2 June 1997 Jun Jul: 56.4 mm (2.2 in), 24 July 2022 Jul Aug: 51.1 mm (2.0 in), 13 August 1997 Aug Sep: 65.5 mm (2.6 in), 29 September 2014 Sep Oct: 66.8 mm (2.6 in), 12 October 2023 Oct Nov: 24.4 mm (1.0 in), 30 November 2019 Nov Dec: 14.5 mm (0.6 in), 1 December 2018 Dec
The wettest day on record for each calendar month at Rapid City WFO. The most was 77.0 mm (3.0 in) on 22 May 2008.
Record daily precipitation for each month at Rapid City WFO
MonthRecord daily precipitation (mm)Date
Jan7.6 mm (0.30 in)3 January 1996
Feb18.0 mm (0.7 in)3 February 1997
Mar24.9 mm (1.0 in)16 March 2018
Apr40.6 mm (1.6 in)6 April 2024
May77.0 mm (3.0 in)22 May 2008
Jun59.2 mm (2.3 in)2 June 1997
Jul56.4 mm (2.2 in)24 July 2022
Aug51.1 mm (2.0 in)13 August 1997
Sep65.5 mm (2.6 in)29 September 2014
Oct66.8 mm (2.6 in)12 October 2023
Nov24.4 mm (1.0 in)30 November 2019
Dec14.5 mm (0.6 in)1 December 2018

Period of Record Coverage

1996 to 2026
Days with data per year at Rapid City WFO 31 years of record at Rapid City WFO, 1996 to 2026. 1 years have data for under 90 percent of days and are left out of rankings: 2026. 1996: 365 of 366 days1997: 364 of 365 days1998: 364 of 365 days1999: 362 of 365 days2000: 365 of 366 days2001: 365 of 365 days2002: 365 of 365 days2003: 364 of 365 days2004: 366 of 366 days2005: 365 of 365 days2006: 364 of 365 days2007: 365 of 365 days2008: 366 of 366 days2009: 365 of 365 days2010: 364 of 365 days2011: 365 of 365 days2012: 366 of 366 days2013: 335 of 365 days2014: 365 of 365 days2015: 365 of 365 days2016: 366 of 366 days2017: 365 of 365 days2018: 365 of 365 days2019: 365 of 365 days2020: 366 of 366 days2021: 365 of 365 days2022: 365 of 365 days2023: 365 of 365 days2024: 366 of 366 days2025: 365 of 365 days2026: 285 of 365 days200020052010201520202025
31 years of record at Rapid City WFO, 1996 to 2026. 1 years have data for under 90 percent of days and are left out of rankings: 2026.
Days with data per year at Rapid City WFO
YearDays with dataShare of yearComplete
1996365100%Yes
1997364100%Yes
1998364100%Yes
199936299%Yes
2000365100%Yes
2001365100%Yes
2002365100%Yes
2003364100%Yes
2004366100%Yes
2005365100%Yes
2006364100%Yes
2007365100%Yes
2008366100%Yes
2009365100%Yes
2010364100%Yes
2011365100%Yes
2012366100%Yes
201333592%Yes
2014365100%Yes
2015365100%Yes
2016366100%Yes
2017365100%Yes
2018365100%Yes
2019365100%Yes
2020366100%Yes
2021365100%Yes
2022365100%Yes
2023365100%Yes
2024366100%Yes
2025365100%Yes
202628578%No

Latest Records

20
Latest records at Rapid City WFO
DateStationRecordValueBeat old record byOld record stoodSignificance
10 October 2026Rapid City WFO, USdaily high max (Provisional)32.2 C (90.0 F)1.6 C (2.9 F)11 years8 of 100 (Routine)
9 October 2026Rapid City WFO, USdaily high max (Provisional)32.8 C (91.0 F)0.6 C (1.1 F)23 years9 of 100 (Routine)
6 October 2026Rapid City WFO, USdaily high min (Provisional)16.1 C (61.0 F)4.4 C (7.9 F)23 years17 of 100 (Routine)
5 October 2026Rapid City WFO, USdaily high max (Tie, Provisional)31.7 C (89.1 F)tie4 years1 of 100 (Routine)
20 September 2026Rapid City WFO, USdaily rain (Provisional)19.1 mm (0.8 in)9.4 mm (0.37 in)7 years17 of 100 (Routine)
5 September 2026Rapid City WFO, USdaily high min (Tie, Provisional)21.1 C (70.0 F)tie4 years1 of 100 (Routine)
18 August 2026Rapid City WFO, USdaily rain (Provisional)19.1 mm (0.8 in)13.5 mm (0.5 in)29 years20 of 100 (Routine)
16 August 2026Rapid City WFO, USdaily rain49.5 mm (1.9 in)48.0 mm (1.9 in)16 years47 of 100 (Notable)
15 August 2026Rapid City WFO, USdaily rain6.9 mm (0.27 in)1.6 mm (0.06 in)16 years9 of 100 (Routine)
5 August 2026Rapid City WFO, USdaily low min (Tie)11.1 C (52.0 F)tie20 years2 of 100 (Routine)
2 August 2026Rapid City WFO, USdaily high max (Tie)38.9 C (102.0 F)tie1 year0 of 100 (Routine)
26 July 2026Rapid City WFO, USdaily high min23.3 C (73.9 F)1.6 C (2.9 F)23 years14 of 100 (Routine)
26 July 2026Rapid City WFO, USdaily high max39.4 C (102.9 F)2.2 C (4.0 F)4 years8 of 100 (Routine)
25 July 2026Rapid City WFO, USall-time high max43.3 C (109.9 F)2.2 C (4.0 F)20 years33 of 100 (Routine)
19 July 2026Rapid City WFO, USdaily high min24.4 C (75.9 F)0.5 C (0.9 F)15 years8 of 100 (Routine)
17 July 2026Rapid City WFO, USdaily high min23.3 C (73.9 F)0.5 C (0.9 F)15 years8 of 100 (Routine)
14 July 2026Rapid City WFO, USdaily high min22.2 C (72.0 F)0.5 C (0.9 F)28 years12 of 100 (Routine)
14 July 2026Rapid City WFO, USdaily high max38.9 C (102.0 F)0.6 C (1.1 F)13 years8 of 100 (Routine)
13 July 2026Rapid City WFO, USdaily high max (Tie)38.9 C (102.0 F)tie23 years2 of 100 (Routine)
12 July 2026Rapid City WFO, USdaily high max40.6 C (105.1 F)2.8 C (5.0 F)1 year9 of 100 (Routine)

Climate Trend

29 complete years, 1996 to 2025
Annual mean temperature at Rapid City WFO as warming stripes, 1996 to 2025 One stripe for each of 29 complete years at Rapid City WFO, 1996 to 2025. Blue stripes are years cooler than the station's own mean of 9.2 C (48.5 F); red stripes are warmer. The coolest year was 1996, at 6.3 C (43.4 F), and the warmest was 2012, at 11.0 C (51.8 F). The strongest colour marks a difference of 2.9 C (5.2 F). 1996: 6.3 C, -2.9 C from the station mean1997: 8.5 C, -0.7 C from the station mean1998: 9.2 C, +0.1 C from the station mean1999: 9.8 C, +0.7 C from the station mean2000: 9.0 C, -0.1 C from the station mean2001: 9.4 C, +0.3 C from the station mean2002: 8.9 C, -0.3 C from the station mean2003: 9.3 C, +0.1 C from the station mean2004: 9.3 C, +0.1 C from the station mean2005: 9.6 C, +0.4 C from the station mean2006: 9.9 C, +0.7 C from the station mean2007: 9.7 C, +0.5 C from the station mean2008: 7.8 C, -1.3 C from the station mean2009: 7.6 C, -1.6 C from the station mean2010: 8.4 C, -0.8 C from the station mean2011: 8.3 C, -0.8 C from the station mean2012: 11.0 C, +1.8 C from the station mean2014: 8.0 C, -1.2 C from the station mean2015: 10.1 C, +1.0 C from the station mean2016: 10.6 C, +1.5 C from the station mean2017: 9.8 C, +0.6 C from the station mean2018: 8.0 C, -1.2 C from the station mean2019: 7.1 C, -2.1 C from the station mean2020: 9.9 C, +0.7 C from the station mean2021: 10.3 C, +1.2 C from the station mean2022: 9.3 C, +0.1 C from the station mean2023: 9.9 C, +0.7 C from the station mean2024: 10.7 C, +1.6 C from the station mean2025: 10.0 C, +0.8 C from the station mean1996200020052010201520202025
One stripe for each of 29 complete years at Rapid City WFO, 1996 to 2025. Blue stripes are years cooler than the station's own mean of 9.2 C (48.5 F); red stripes are warmer. The coolest year was 1996, at 6.3 C (43.4 F), and the warmest was 2012, at 11.0 C (51.8 F). The strongest colour marks a difference of 2.9 C (5.2 F).
Annual mean temperature at Rapid City WFO as warming stripes, 1996 to 2025
YearAnnual mean temperatureDifference from the station mean
19966.3 C-2.85 C
19978.5 C-0.67 C
19989.2 C+0.06 C
19999.8 C+0.67 C
20009.0 C-0.14 C
20019.4 C+0.26 C
20028.9 C-0.29 C
20039.3 C+0.11 C
20049.3 C+0.10 C
20059.6 C+0.43 C
20069.9 C+0.70 C
20079.7 C+0.51 C
20087.8 C-1.33 C
20097.6 C-1.55 C
20108.4 C-0.78 C
20118.3 C-0.83 C
201211.0 C+1.84 C
20148.0 C-1.17 C
201510.1 C+0.98 C
201610.6 C+1.47 C
20179.8 C+0.62 C
20188.0 C-1.15 C
20197.1 C-2.11 C
20209.9 C+0.71 C
202110.3 C+1.16 C
20229.3 C+0.09 C
20239.9 C+0.73 C
202410.7 C+1.58 C
202510.0 C+0.85 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

1996 to 2026
Yearly extremes at Rapid City WFO: the record and the median year
MeasureRecordYear of the recordMedian yearYears with a value
Hottest day (TXx)43.3 C (109.9 F)202638.3 C (100.9 F)31
Coldest night (TNn)-30.6 C (-23.1 F)1996-26.1 C (-15.0 F)31
Wettest day (Rx1day)77.0 mm (3.0 in)200842.7 mm (1.7 in)31
Wettest five days (Rx5day)136.7 mm (5.4 in)199662.7 mm (2.5 in)31
Longest dry spell (CDD)65 days201235 days31

Hottest day (TXx)

Hottest day (TXx) at Rapid City WFO by year The hottest day of the year at Rapid City WFO, 1996 to 2026. The record is 43.3 C (109.9 F) in 2026, marked on the chart; the median year is 38.3 C (100.9 F). 32.53537.54042.545200020052010201520202025Record: 43.3 C (109.9 F) in 2026
The hottest day of the year at Rapid City WFO, 1996 to 2026. The record is 43.3 C (109.9 F) in 2026, marked on the chart; the median year is 38.3 C (100.9 F).
Hottest day (TXx) at Rapid City WFO by year
YearHottest day (TXx)
199635.6 C (96.1 F)
199735.6 C (96.1 F)
199838.9 C (102.0 F)
199936.7 C (98.1 F)
200037.8 C (100.0 F)
200138.3 C (100.9 F)
200240.6 C (105.1 F)
200340.0 C (104.0 F)
200438.3 C (100.9 F)
200540.6 C (105.1 F)
200641.1 C (106.0 F)
200740.6 C (105.1 F)
200836.7 C (98.1 F)
200935.6 C (96.1 F)
201037.8 C (100.0 F)
201138.3 C (100.9 F)
201241.1 C (106.0 F)
201338.3 C (100.9 F)
201436.7 C (98.1 F)
201538.3 C (100.9 F)
201638.3 C (100.9 F)
201738.9 C (102.0 F)
201838.9 C (102.0 F)
201933.9 C (93.0 F)
202038.9 C (102.0 F)
202141.1 C (106.0 F)
202240.6 C (105.1 F)
202338.3 C (100.9 F)
202440.6 C (105.1 F)
202539.4 C (102.9 F)
202643.3 C (109.9 F)

Coldest night (TNn)

Coldest night (TNn) at Rapid City WFO by year The coldest night of the year at Rapid City WFO, 1996 to 2026. The record is -30.6 C (-23.1 F) in 1996, marked on the chart; the median year is -26.1 C (-15.0 F). -35-30-25-20-15200020052010201520202025Record: -30.6 C (-23.1 F) in 1996
The coldest night of the year at Rapid City WFO, 1996 to 2026. The record is -30.6 C (-23.1 F) in 1996, marked on the chart; the median year is -26.1 C (-15.0 F).
Coldest night (TNn) at Rapid City WFO by year
YearColdest night (TNn)
1996-30.6 C (-23.1 F)
1997-27.2 C (-17.0 F)
1998-26.1 C (-15.0 F)
1999-22.2 C (-8.0 F)
2000-27.8 C (-18.0 F)
2001-21.1 C (-6.0 F)
2002-22.8 C (-9.0 F)
2003-23.9 C (-11.0 F)
2004-23.9 C (-11.0 F)
2005-25.0 C (-13.0 F)
2006-26.7 C (-16.1 F)
2007-26.1 C (-15.0 F)
2008-28.3 C (-18.9 F)
2009-23.3 C (-9.9 F)
2010-25.6 C (-14.1 F)
2011-25.6 C (-14.1 F)
2012-22.2 C (-8.0 F)
2013-25.6 C (-14.1 F)
2014-26.7 C (-16.1 F)
2015-20.6 C (-5.1 F)
2016-26.1 C (-15.0 F)
2017-27.2 C (-17.0 F)
2018-27.8 C (-18.0 F)
2019-25.6 C (-14.1 F)
2020-19.4 C (-2.9 F)
2021-26.7 C (-16.1 F)
2022-27.8 C (-18.0 F)
2023-26.1 C (-15.0 F)
2024-30.6 C (-23.1 F)
2025-28.9 C (-20.0 F)
2026-24.4 C (-11.9 F)

Wettest day (Rx1day)

Wettest day (Rx1day) at Rapid City WFO by year The wettest day of the year at Rapid City WFO, 1996 to 2026. The record is 77.0 mm (3.0 in) in 2008, marked on the chart; the median year is 42.7 mm (1.7 in). 20406080200020052010201520202025Record: 77.0 mm (3.0 in) in 2008
The wettest day of the year at Rapid City WFO, 1996 to 2026. The record is 77.0 mm (3.0 in) in 2008, marked on the chart; the median year is 42.7 mm (1.7 in).
Wettest day (Rx1day) at Rapid City WFO by year
YearWettest day (Rx1day)
199642.4 mm (1.7 in)
199767.3 mm (2.6 in)
199849.8 mm (2.0 in)
199949.8 mm (2.0 in)
200032.8 mm (1.3 in)
200142.7 mm (1.7 in)
200237.6 mm (1.5 in)
200325.9 mm (1.0 in)
200436.8 mm (1.4 in)
200537.1 mm (1.5 in)
200642.4 mm (1.7 in)
200740.9 mm (1.6 in)
200877.0 mm (3.0 in)
200955.1 mm (2.2 in)
201042.9 mm (1.7 in)
201155.6 mm (2.2 in)
201225.9 mm (1.0 in)
201357.2 mm (2.3 in)
201465.5 mm (2.6 in)
201548.8 mm (1.9 in)
201633.3 mm (1.3 in)
201738.1 mm (1.5 in)
201845.5 mm (1.8 in)
201951.6 mm (2.0 in)
202024.6 mm (1.0 in)
202133.5 mm (1.3 in)
202256.4 mm (2.2 in)
202366.8 mm (2.6 in)
202440.6 mm (1.6 in)
202528.4 mm (1.1 in)
202649.5 mm (1.9 in)

Wettest five days (Rx5day)

Wettest five days (Rx5day) at Rapid City WFO by year The wettest five days of the year at Rapid City WFO, 1996 to 2026. The record is 136.7 mm (5.4 in) in 1996, marked on the chart; the median year is 62.7 mm (2.5 in). 050100150200020052010201520202025Record: 136.7 mm (5.4 in) in 1996
The wettest five days of the year at Rapid City WFO, 1996 to 2026. The record is 136.7 mm (5.4 in) in 1996, marked on the chart; the median year is 62.7 mm (2.5 in).
Wettest five days (Rx5day) at Rapid City WFO by year
YearWettest five days (Rx5day)
1996136.7 mm (5.4 in)
1997100.8 mm (4.0 in)
199875.1 mm (3.0 in)
199982.1 mm (3.2 in)
200062.7 mm (2.5 in)
200155.9 mm (2.2 in)
200245.7 mm (1.8 in)
200344.0 mm (1.7 in)
200466.7 mm (2.6 in)
200561.3 mm (2.4 in)
200653.1 mm (2.1 in)
200751.5 mm (2.0 in)
2008134.5 mm (5.3 in)
200959.7 mm (2.4 in)
201063.1 mm (2.5 in)
201196.7 mm (3.8 in)
201239.6 mm (1.6 in)
201379.8 mm (3.1 in)
2014100.8 mm (4.0 in)
201579.6 mm (3.1 in)
201636.9 mm (1.5 in)
201752.6 mm (2.1 in)
2018110.1 mm (4.3 in)
201994.8 mm (3.7 in)
202031.5 mm (1.2 in)
202148.8 mm (1.9 in)
202258.2 mm (2.3 in)
202384.1 mm (3.3 in)
202450.2 mm (2.0 in)
202544.5 mm (1.8 in)
202677.3 mm (3.0 in)

Longest dry spell (CDD)

Longest dry spell (CDD) at Rapid City WFO by year The longest dry spell of the year at Rapid City WFO, 1996 to 2026. The record is 65 days in 2012, marked on the chart; the median year is 35 days. 020406080200020052010201520202025Record: 65 days in 2012
The longest dry spell of the year at Rapid City WFO, 1996 to 2026. The record is 65 days in 2012, marked on the chart; the median year is 35 days.
Longest dry spell (CDD) at Rapid City WFO by year
YearLongest dry spell (CDD)
199628 days
199755 days
199852 days
199946 days
200025 days
200131 days
200239 days
200320 days
200461 days
200528 days
200651 days
200753 days
200826 days
200926 days
201042 days
201123 days
201265 days
201326 days
201428 days
201535 days
201619 days
201733 days
201826 days
201917 days
202035 days
202135 days
202239 days
202350 days
202441 days
202515 days
202638 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 Rapid City WFO falls on 7 May and the median first autumn frost on 9 October, which leaves a median of 160 days between them.

Fitted over all years, the growing season changes by +2.2 days per decade at this station.

Frost dates and growing season at Rapid City WFO
MeasureMedian, all yearsEarliest periodRecent period (1996 to 2025)Recent against earliestFitted trend
Last spring frost7 Mayn/a7 Mayn/a-0.5 days per decade
First autumn frost9 Octobern/a9 Octobern/a+1.7 days per decade
Growing days160 daysn/a160 daysn/a+2.2 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 43.5 mm (1.7 in) of rain is expected about once in 2 years. A day with at least 84.1 mm (3.3 in) of rain is expected about once in 100 years.

Rainfall return levels at Rapid City WFO: the daily rain expected about once in a given number of years
Expected about once inA day with at leastNote
2 years43.5 mm (1.7 in)
5 years55.8 mm (2.2 in)
10 years63.4 mm (2.5 in)
25 years72.2 mm (2.8 in)
50 years78.4 mm (3.1 in)Longer than the 30 years of record
100 years84.1 mm (3.3 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: 77.0 mm (3.0 in) in 2008; 67.3 mm (2.6 in) in 1997; 66.8 mm (2.6 in) in 2023.

Download the Data

  • Data for Rapid City WFO standing records by year: CSV or JSON. Field meanings are on the data page.
  • Data for Rapid City WFO 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 2026-10-14 (14 October 2026). Records are computed by this site and are not official.

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