Rapid City, SD

South Dakota · Records since 1942–2026

☀️ 79Β°F Feels like 72Β°
Currently in Rapid City
As of 12:30 PM MDT

Records for September 11

🔥 Record High

100Β°F

September 11, 2025

+22Β° from 78Β° normal

❄ Record Low

29Β°F

September 11, 1989

-19Β° from 48Β° normal
🌞 Normal high: 78Β°F 🌑 Normal low: 48Β°F 1991–2020 normals

All-Time Records β€” Rapid City

🔥
112°F
Hottest Day Ever
Jul 25, 2026
-31°F
Coldest Day Ever
Feb 2, 1996
🌧
3.78"
Wettest Day Ever
Jun 15, 1963
20.0"
Most Snow in One Day
Apr 9, 2013

First & Last Dates β€” Rapid City

How early and how late each seasonal turning point has ever arrived, across the full period of record

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Range ever recorded Normal date (1991–2020)
186 days
Longest growing season
1977
110 days
Shortest growing season
1949
135 days
Normal growing season
1991–2020 average

Top 10 Record Highs β€” September 11

# Temp Date
🏆 100Β°F September 11, 2025
2 97Β°F September 11, 2024
3 94Β°F September 11, 1990
4 94Β°F September 11, 1948
5 93Β°F September 11, 1993
6 93Β°F September 11, 1967
7 93Β°F September 11, 1962
8 93Β°F September 11, 1959
9 92Β°F September 11, 2011
10 92Β°F September 11, 1976

Top 5 Record Lows β€” September 11

# Temp Date
🥶 29Β°F September 11, 1989
2 33Β°F September 11, 2014
3 37Β°F September 11, 2022
4 37Β°F September 11, 1955
5 37Β°F September 11, 1949
About this data — Records are sourced from the NOAA Threadex dataset via RCC ACIS, a quality-controlled record for long-term climate stations. Threadex adjusts for station relocations and observation-time changes, making records comparable across all years since 1942–2026. Climate normals represent the 1991–2020 average.

Heat Wave Summary β€” Rapid City

threshold: 96Β°F (90th percentile of historical Jun–Aug highs)
3.7
Avg heat wave length
days (historical)
103Β°
Avg peak temp
during heat waves
7
Dangerous nights 2026
Overnights β‰₯ 70Β°F
2
Heat waves 2026
so far

Days β‰₯ 90Β°F Per Year

1942–2026
54
2026 so far
32
Avg/year 1970–2025
35
Avg/year (last 10 complete)
59
Most in a year (1988)

Average Daily High by Decade

Full year Β· complete decades only


Longest Heat Waves β€” Rapid City

# Dates Days Peak Avg High Avg Overnight Low
🏆 Jul 25, 1987 – Aug 2, 1987 9 105Β°F (Jul 25) 102Β°F 68Β°F
2 Jul 18, 2012 – Jul 24, 2012 7 107Β°F (Jul 19) 100Β°F 65Β°F
3 Jul 10, 2026 – Jul 16, 2026 7 105Β°F (Jul 12) 101Β°F 66Β°F
4 Jul 26, 1988 – Aug 1, 1988 7 104Β°F (Jul 30) 101Β°F 64Β°F
5 Aug 2, 2001 – Aug 8, 2001 7 104Β°F (Aug 7) 100Β°F 66Β°F
6 Aug 22, 1991 – Aug 28, 1991 7 103Β°F (Aug 25) 100Β°F 63Β°F
7 Jul 24, 2026 – Jul 29, 2026 6 112Β°F (Jul 25) 103Β°F 66Β°F
8 Jul 8, 1954 – Jul 13, 1954 6 109Β°F (Jul 12) 102Β°F 68Β°F
9 Jul 18, 1964 – Jul 23, 1964 6 104Β°F (Jul 21) 100Β°F 66Β°F
10 Jul 29, 1955 – Aug 3, 1955 6 102Β°F (Aug 1) 99Β°F 68Β°F

Heat Waves Per Year


Warm Summer Nights (Jun–Aug)

Nights where the overnight low exceeded the 1991–2020 normal low

59
2026 total
above-normal nights
44.8
Avg / summer
1970–2020
74
Most in a summer
2007

Above-Normal Summer Nights Per Year

Average June–August Low by Decade

Overnight lows Β· complete decades only

Precipitation

Annual totals and trend across the full period of record · see this year's standing →

Monthly Precipitation β€” Last 24 Months

Blue = actual Β· dashed line = monthly normal

Annual Precipitation Per Year (1942–2026)

Blue = above average Β· tan = below average Β· gold = 2026 (partial)
Since 1942, annual totals have trended +0.19" per decade, about +1.6" across the record.

Heavy Rain Days Per Year (β‰₯ 1.0")

Compare year-to-year changes in days with heavy rainfall (β‰₯ 1.0")

This Year β€” 2026

How Rapid City is tracking against normal, year to date

Daily High Temperature vs Normal

Above normal Below normal

172 of 253 days with data were above the 1991–2020 normal high for their date.


Precipitation, Year to Date

9.81"
2026 YTD
Normal: 14.39"
-4.58"
0.19"
September so far
September normal: 1.22"
-1.03"
3
2026 heavy rain days
Days with β‰₯ 1.0"

Accumulation vs. Normal

Running total since Jan 1 against the normal pace for the same date · Rapid City is 4.58" behind the normal pace

Period Review β€” Jun 1 – Aug 31, 2026

Any window, evaluated against every other year on record — 92 days

72.5Β°F
Average temperature
9th-warmest of 84
+2.9Β°
vs. average
Normal: 69.6Β°F (1991–2020)
4.06"
Precipitation
16th-driest of 84
-2.67"
vs. average
Normal: 6.73" · 60% of normal

Average Temperature by Year β€” Jun 1 – Aug 31

1943–2026 · 2026 highlighted · trend +0.16Β° per decade (warming since 1943)

Precipitation by Year β€” Jun 1 – Aug 31

1943–2026 · 2026 highlighted · trend -0.06" per decade (drier since 1943)


Warmest Jun 1 – Aug 31 on Record

# Year Avg Temp
1 1988 74.7Β°F
2 2007 74.4Β°F
3 2006 74.2Β°F
4 1961 73.9Β°F
5 2012 73.7Β°F
6 1959 73.2Β°F
7 2002 73.1Β°F
8 2021 72.5Β°F
9 2026 72.5Β°F
10 1963 72.1Β°F

Coolest Jun 1 – Aug 31 on Record

# Year Avg Temp
1 1992 64.2Β°F
2 1993 64.7Β°F
3 2009 65.3Β°F
4 1945 66.0Β°F
5 1951 66.1Β°F
6 1950 66.2Β°F
7 1968 66.4Β°F
8 1972 66.5Β°F
9 1944 66.6Β°F
10 2014 66.7Β°F

Wettest Jun 1 – Aug 31 on Record

# Year Total
1 2015 14.54"
2 2018 13.14"
3 1968 11.90"
4 2019 11.36"
5 2014 11.21"
6 1997 11.03"
7 1948 10.57"
8 1945 10.10"
9 1979 10.03"
10 1944 9.96"

Driest Jun 1 – Aug 31 on Record

# Year Total
1 1994 2.23"
2 2002 2.31"
3 1973 2.84"
4 2024 2.87"
5 1974 3.15"
6 1961 3.30"
7 2003 3.40"
8 2006 3.45"
9 1988 3.45"
10 1989 3.56"
About this data. Pick any start and end date and this becomes the same kind of review as the Month and Fall tabs, just for exactly the window you asked for — the generalized version of the same engine, evaluated across every year on record. Average temperature is the mean of each day's (high + low) / 2; precipitation is the sum of daily totals. A year missing more than about a fifth of the window's days is excluded from the temperature ranking; any missing day excludes a year from the precipitation ranking, since an unreported day is unreported rain. Ranges that cross from December into January aren't supported yet. Normals are the 1991–2020 mean for the same window.