Kennebec, South Dakota climate: Normal weather by month, frost dates and records
Kennebec's normal year runs from 9°F January nights to 90°F July afternoons, with 20.8 inches of precipitation and 40 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 8.9°C, January lows of −13°C, July highs of 32°C, 528 mm of precipitation a year.
- NOAA stationKennebec
- Station IDUSC00394516
- Location43.90°N 99.86°W
- Elevation1,681 ft (512 m)
- From the centerunder 1 mile
- Population285
On October 22, the normal high in Kennebec is 60°F and the normal low 33°F, and the chance of measurable rain or snow is 19%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Kennebec.
- Jan 32° 9°
- Feb 36° 13°
- Mar 49° 23°
- Apr 62° 33°
- May 72° 45°
- Jun 82° 56°
- Jul 90° 61°
- Aug 88° 59°
- Sep 80° 50°
- Oct 64° 36°
- Nov 47° 22°
- Dec 34° 13°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Kennebec each month?
July is the warmest month, with normal highs of 90°F; January the coldest, with normal lows of 9°F. The most precipitation falls in June (3.48 in), the least in January (0.45 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 32°F | 9°F | 20.4°F | 0.45 | 5.5 | 4 | <1 | 31 | 9 h 10 min |
| February | 36°F | 13°F | 24.6°F | 0.59 | 7.6 | 5 | <1 | 27 | 10 h 30 min |
| March | 49°F | 23°F | 35.9°F | 0.96 | 5.5 | 5 | <1 | 25 | 11 h 50 min |
| April | 62°F | 33°F | 47.3°F | 2.34 | 6.2 | 9 | <1 | 14 | 13 h 20 min |
| May | 72°F | 45°F | 58.6°F | 3.29 | 0.0 | 10 | 2 | 3 | 14 h 40 min |
| June | 82°F | 56°F | 69.0°F | 3.48 | 0.0 | 10 | 6 | <1 | 15 h 30 min |
| July | 90°F | 61°F | 75.6°F | 2.84 | 0.0 | 8 | 16 | <1 | 15 h 10 min |
| August | 88°F | 59°F | 73.5°F | 2.31 | 0.0 | 7 | 13 | <1 | 14 h |
| September | 80°F | 50°F | 64.9°F | 1.72 | 0.0 | 6 | 6 | 1 | 12 h 40 min |
| October | 64°F | 36°F | 49.7°F | 1.63 | 1.6 | 7 | 1 | 11 | 11 h 10 min |
| November | 47°F | 22°F | 34.7°F | 0.71 | 6.0 | 5 | <1 | 25 | 9 h 40 min |
| December | 34°F | 13°F | 23.4°F | 0.47 | 7.2 | 5 | <1 | 30 | 9 h |
| Year (annual) | 61°F | 35°F | 48.1°F | 20.79 | 39.6 | 80 | 44 | 166 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 0°C | −13°C | −6.4°C | 11 mm | 14 cm |
| February | 2°C | −11°C | −4.1°C | 15 mm | 19 cm |
| March | 9°C | −5°C | 2.2°C | 24 mm | 14 cm |
| April | 16°C | 0°C | 8.5°C | 59 mm | 16 cm |
| May | 22°C | 7°C | 14.8°C | 84 mm | 0 cm |
| June | 28°C | 13°C | 20.6°C | 88 mm | 0 cm |
| July | 32°C | 16°C | 24.2°C | 72 mm | 0 cm |
| August | 31°C | 15°C | 23.1°C | 59 mm | 0 cm |
| September | 27°C | 10°C | 18.3°C | 44 mm | 0 cm |
| October | 18°C | 2°C | 9.8°C | 41 mm | 4 cm |
| November | 8°C | −5°C | 1.5°C | 18 mm | 15 cm |
| December | 1°C | −11°C | −4.8°C | 12 mm | 18 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00394516; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Kennebec?
Normal highs sit between 65°F and 85°F in May, June and September. Of those, September has the fewest days with rain (6).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00394516.
When is the last frost in Kennebec?
In Kennebec, the last spring frost (32°F) comes after May 12 in half of years and after May 26 in one year in ten; the first autumn frost comes before September 28 in half of years and before September 15 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- May 121 year in 10 after May 26; 9 in 10 after April 29
- First autumn frost, half of years before
- September 281 year in 10 before September 15; 9 in 10 before October 10
NOAA puts the median frost-free season at 137 days, and the season without a hard freeze (28°F) at 154 days.
A hard freeze (28°F) comes after May 3 in half of springs and before October 5 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Kennebec in zone 5a in ZIP code 57544, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Kennebec's NOAA station is in zone 4b: the coldest night of a typical year reaches −21°F (30 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in South Dakota · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00394516; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get in Kennebec?
In a normal year in Kennebec, 44 days a year reach 90°F (8 of them 100°F or more), 166 nights fall to 32°F or colder and 80 days bring measurable precipitation.
- Days at 90°F or more
- 44a normal year
- Days at 100°F or more
- 8a normal year
- Nights at 32°F or colder
- 166a normal year
- Days that stay below freezing
- 49high of 32°F or less
- Days with 0.01 inch of precipitation
- 80a normal year
- Days with 1 inch of snow or more
- 14a normal year
The highest temperature in this station's record (since 1893) is 119°F, on July 5, 1936; the lowest is −45°F, on February 9, 1899.
The wettest calendar year on that record is 2019, with 35.74 in; the snowiest season is 2000–01, with 73.2 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00394516; records: ACIS (NOAA Regional Climate Centers), station USC00394516. Records use complete months only; a month missing more than three days is left out.
How sunny is Kennebec?
Over a year 78% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Kennebec, 4.2 kWh per square metre a day. July is the sunniest month (86%) and April the cloudiest (72%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 75% | 2.0 |
| February | 76% | 3.0 |
| March | 72% | 3.9 |
| April | 72% | 5.0 |
| May | 74% | 5.9 |
| June | 80% | 6.7 |
| July | 86% | 6.9 |
| August | 84% | 5.8 |
| September | 82% | 4.6 |
| October | 76% | 3.1 |
| November | 75% | 2.1 |
| December | 72% | 1.6 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Kennebec need?
A normal year in Kennebec brings 7,042 heating degree days, 31% more than the median U.S. place (5,373), and 929 cooling degree days, 2% more than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 3,084 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,383 | 0 |
| February | 1,132 | 0 |
| March | 904 | 0 |
| April | 536 | 3 |
| May | 238 | 41 |
| June | 40 | 160 |
| July | 5 | 332 |
| August | 13 | 276 |
| September | 111 | 108 |
| October | 483 | 9 |
| November | 909 | 0 |
| December | 1,289 | 0 |
| Year (annual) | 7,042 | 929 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00394516. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Kennebec been warmer than normal lately?
2025 averaged 50.3°F, 2.2°F above the 1991-2020 normal of 48.1°F. 4 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 50.4°F | +2.3°F | 21.30 | 30.1 |
| 2022 | 48.1°F | at normal | 19.17 | – |
| 2023 | 48.8°F | +0.7°F | 26.30 | – |
| 2024 | 50.3°F | +2.2°F | 16.35 | – |
| 2025 | 50.3°F | +2.2°F | 21.86 | – |
Over 88 complete years from 1893 to 2025, the station's annual mean temperature rose at a fitted 3.0°F per century (+0.17°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00394516; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Kennebec's climate compare?
Kennebec is warmer than 88 of the other 99 places with their own NOAA record in South Dakota, and wetter than 32. Across the 7,247 U.S. stations with normals, its annual mean of 48.1°F is warmer than 32%.
In the Köppen classification computed from these normals, Kennebec is Dfa: continental, no dry season, hot summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Kennebec share this climate record?
Reliance has no NOAA station with 1991-2020 normals of its own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Reliance, SD127 people · 13 mi E
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Kennebec's climate
What is the coldest month in Kennebec?
January, with a normal high of 32°F and a normal low of 9°F. The warmest is July (90°F by day, 61°F at night).
Does it snow in Kennebec?
Yes: 40 inches in a normal year, falling on 18 days with 0.1 inch or more, the most in February (7.6 inches).
What is the rainiest month in Kennebec?
June, with 3.48 in of precipitation in a normal year; the driest is January with 0.45 in.
What plant hardiness zone is Kennebec in?
The USDA's 2023 map puts Kennebec in zone 5a in ZIP code 57544, the nearest ZIP area. By the same method at Kennebec's NOAA station, the coldest night of a typical year reaches −21°F (30 years, 1991-2020): zone 4b.
How late can frost come in Kennebec?
In half of years the last 32°F night comes after May 12; in one year in ten it comes after May 26. Waiting until May 26 leaves about a one-in-ten chance of a later frost.
Nearby and next
- South Dakota climateThe statewide normals and every place in the state
- Presho, SD16 miles from this station, 45.7°F a year
- Lake Sharpe Project, SD23 miles from this station, 46.7°F a year
- Pierre (24 mi S), SD26 miles from this station, 47.0°F a year
- Chamberlain, SD29 miles from this station, 48.2°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made