Selby, South Dakota climate: Normal weather by month, frost dates and records
Selby's normal year runs from 4°F January nights to 84°F July afternoons, with 19.2 inches of precipitation and 33 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 6.5°C, January lows of −16°C, July highs of 29°C, 489 mm of precipitation a year.
- NOAA stationSelby
- Station IDUSC00397545
- Location45.51°N 100.04°W
- Elevation1,908 ft (582 m)
- Population606
On October 22, the normal high in Selby is 54°F and the normal low 31°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 Selby.
- Jan 23° 4°
- Feb 28° 8°
- Mar 41° 19°
- Apr 55° 31°
- May 67° 44°
- Jun 78° 55°
- Jul 84° 60°
- Aug 83° 58°
- Sep 74° 48°
- Oct 58° 34°
- Nov 41° 21°
- Dec 28° 10°
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 Selby each month?
July is the warmest month, with normal highs of 84°F; January the coldest, with normal lows of 4°F. The most precipitation falls in June (3.45 in), the least in January (0.40 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 23°F | 4°F | 13.6°F | 0.40 | 4.0 | 5 | <1 | 31 | 9 h |
| February | 28°F | 8°F | 17.7°F | 0.57 | 7.0 | 5 | <1 | 28 | 10 h 20 min |
| March | 41°F | 19°F | 29.9°F | 0.79 | 5.1 | 6 | <1 | 27 | 11 h 50 min |
| April | 55°F | 31°F | 43.0°F | 1.60 | 4.4 | 7 | <1 | 18 | 13 h 30 min |
| May | 67°F | 44°F | 55.7°F | 2.82 | 0.2 | 10 | 1 | 3 | 14 h 50 min |
| June | 78°F | 55°F | 66.2°F | 3.45 | 0.0 | 11 | 2 | <1 | 15 h 40 min |
| July | 84°F | 60°F | 72.2°F | 2.68 | 0.0 | 8 | 7 | <1 | 15 h 20 min |
| August | 83°F | 58°F | 70.3°F | 2.41 | 0.0 | 8 | 6 | <1 | 14 h 10 min |
| September | 74°F | 48°F | 60.9°F | 1.64 | 0.0 | 6 | 2 | 1 | 12 h 40 min |
| October | 58°F | 34°F | 45.7°F | 1.83 | 1.6 | 7 | <1 | 14 | 11 h |
| November | 41°F | 21°F | 30.7°F | 0.54 | 3.5 | 4 | <1 | 27 | 9 h 30 min |
| December | 28°F | 10°F | 18.8°F | 0.51 | 7.6 | 4 | <1 | 31 | 8 h 40 min |
| Year (annual) | 55°F | 33°F | 43.7°F | 19.24 | 33.4 | 82 | 18 | 179 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −5°C | −16°C | −10.2°C | 10 mm | 10 cm |
| February | −2°C | −14°C | −7.9°C | 14 mm | 18 cm |
| March | 5°C | −7°C | −1.2°C | 20 mm | 13 cm |
| April | 13°C | −1°C | 6.1°C | 41 mm | 11 cm |
| May | 20°C | 7°C | 13.2°C | 72 mm | 1 cm |
| June | 25°C | 13°C | 19.0°C | 88 mm | 0 cm |
| July | 29°C | 16°C | 22.3°C | 68 mm | 0 cm |
| August | 28°C | 14°C | 21.3°C | 61 mm | 0 cm |
| September | 23°C | 9°C | 16.1°C | 42 mm | 0 cm |
| October | 14°C | 1°C | 7.6°C | 46 mm | 4 cm |
| November | 5°C | −6°C | −0.7°C | 14 mm | 9 cm |
| December | −2°C | −12°C | −7.3°C | 13 mm | 19 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00397545; 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 Selby?
Normal highs sit between 65°F and 85°F in May, June, July, August 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 USC00397545.
When is the last frost in Selby?
In Selby, the last spring frost (32°F) comes after May 8 in half of years and after May 21 in one year in ten; the first autumn frost comes before October 1 in half of years and before September 19 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 81 year in 10 after May 21; 9 in 10 after April 26
- First autumn frost, half of years before
- October 11 year in 10 before September 19; 9 in 10 before October 14
NOAA puts the median frost-free season at 145 days, and the season without a hard freeze (28°F) at 162 days.
A hard freeze (28°F) comes after April 30 in half of springs and before October 9 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Selby in zone 4b in ZIP code 57472, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Selby's NOAA station is in zone 4b: the coldest night of a typical year reaches −23°F (24 complete years).
Frost dates for every NOAA station in South Dakota · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00397545; 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 Selby?
In a normal year in Selby, 18 days a year reach 90°F (1 of them 100°F or more), 179 nights fall to 32°F or colder and 82 days bring measurable precipitation.
- Days at 90°F or more
- 18a normal year
- Days at 100°F or more
- 1a normal year
- Nights at 32°F or colder
- 179a normal year
- Days that stay below freezing
- 79high of 32°F or less
- Days with 0.01 inch of precipitation
- 82a normal year
- Days with 1 inch of snow or more
- 12a normal year
The highest temperature in this station's record (since 1907) is 112°F, on July 16, 2006; the lowest is −41°F, on January 12, 1912.
The wettest calendar year on that record is 2013, with 26.60 in; the snowiest season is 2018–19, with 72.1 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00397545; records: ACIS (NOAA Regional Climate Centers), station USC00397545. Records use complete months only; a month missing more than three days is left out.
How sunny is Selby?
Over a year 78% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Selby, 4.1 kWh per square metre a day. July is the sunniest month (86%) and December the cloudiest (69%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 75% | 1.8 |
| February | 79% | 2.9 |
| March | 73% | 3.8 |
| April | 72% | 5.0 |
| May | 74% | 5.9 |
| June | 80% | 6.7 |
| July | 86% | 6.9 |
| August | 84% | 5.8 |
| September | 81% | 4.4 |
| October | 73% | 2.9 |
| November | 73% | 1.9 |
| December | 69% | 1.4 |
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 Selby need?
A normal year in Selby brings 8,337 heating degree days, 55% more than the median U.S. place (5,373), and 623 cooling degree days, 31% fewer than the median (908). Eight months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,513 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,593 | 0 |
| February | 1,326 | 0 |
| March | 1,088 | 0 |
| April | 663 | 1 |
| May | 312 | 22 |
| June | 70 | 106 |
| July | 14 | 238 |
| August | 28 | 191 |
| September | 183 | 62 |
| October | 601 | 4 |
| November | 1,029 | 0 |
| December | 1,431 | 0 |
| Year (annual) | 8,337 | 623 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00397545. 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 Selby been warmer than normal lately?
2022 averaged 42.2°F, 1.5°F below the 1991-2020 normal of 43.7°F. 1 of the 2 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 46.3°F | +2.6°F | 18.41 | 8.9 |
| 2022 | 42.2°F | −1.5°F | 15.32 | 25.8 |
Over 50 complete years from 1963 to 2022, the station's annual mean temperature rose at a fitted 2.2°F per century (+0.12°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00397545; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Selby's climate compare?
Selby is warmer than 19 of the other 99 places with their own NOAA record in South Dakota, and wetter than 20. Across the 7,247 U.S. stations with normals, its annual mean of 43.7°F is warmer than 14%.
In the Köppen classification computed from these normals, Selby 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 Selby share this climate record?
4 places have no NOAA station with 1991-2020 normals of their 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.
- Java, SD120 people · 7 mi E
- Akaska, SD82 people · 13 mi S
- Mound City, SD66 people · 15 mi N
- Lowry, SD6 people · 14 mi S
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 Selby's climate
What is the coldest month in Selby?
January, with a normal high of 23°F and a normal low of 4°F. The warmest is July (84°F by day, 60°F at night).
Does it snow in Selby?
Yes: 33 inches in a normal year, falling on 22 days with 0.1 inch or more, the most in December (7.6 inches).
What is the rainiest month in Selby?
June, with 3.45 in of precipitation in a normal year; the driest is January with 0.40 in.
What plant hardiness zone is Selby in?
The USDA's 2023 map puts Selby in zone 4b in ZIP code 57472, the nearest ZIP area. By the same method at Selby's NOAA station, the coldest night of a typical year reaches −23°F (24 years, 1991-2020): zone 4b.
How late can frost come in Selby?
In half of years the last 32°F night comes after May 8; in one year in ten it comes after May 21. Waiting until May 21 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
- Mobridge, SD18 miles from this station, 46.4°F a year
- Eureka, SD27 miles from this station, 41.8°F a year
- Pollock, SD30 miles from this station, 44.3°F a year
- Roscoe, SD34 miles from this station, 42.6°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made