Andover, South Dakota climate: Normal weather by month, frost dates and records
Andover's normal year runs from 5°F January nights to 82°F July afternoons, with 24.0 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 6.8°C, January lows of −15°C, July highs of 28°C, 609 mm of precipitation a year.
- NOAA stationAndover #2
- Station IDUSC00390120
- Location45.41°N 97.91°W
- Elevation1,478 ft (451 m)
- From the centerunder 1 mile
- Population68
On October 22, the normal high in Andover is 54°F and the normal low 34°F.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Andover.
- Jan 22° 5°
- Feb 27° 9°
- Mar 40° 21°
- Apr 56° 33°
- May 68° 46°
- Jun 77° 56°
- Jul 82° 61°
- Aug 80° 59°
- Sep 73° 50°
- Oct 58° 37°
- Nov 41° 23°
- Dec 28° 11°
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 Andover each month?
July is the warmest month, with normal highs of 82°F; January the coldest, with normal lows of 5°F. The most precipitation falls in June (3.92 in), the least in January (0.57 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 22°F | 5°F | 13.0°F | 0.57 | – | <1 | 31 | 9 h |
| February | 27°F | 9°F | 17.9°F | 0.57 | – | <1 | 27 | 10 h 20 min |
| March | 40°F | 21°F | 30.9°F | 0.92 | – | <1 | 25 | 11 h 50 min |
| April | 56°F | 33°F | 44.4°F | 2.00 | – | <1 | 14 | 13 h 30 min |
| May | 68°F | 46°F | 57.0°F | 3.19 | – | 1 | 3 | 14 h 50 min |
| June | 77°F | 56°F | 66.8°F | 3.92 | – | 2 | <1 | 15 h 40 min |
| July | 82°F | 61°F | 71.5°F | 3.81 | – | 5 | <1 | 15 h 20 min |
| August | 80°F | 59°F | 69.8°F | 2.74 | – | 3 | <1 | 14 h 10 min |
| September | 73°F | 50°F | 61.4°F | 2.47 | – | 1 | <1 | 12 h 40 min |
| October | 58°F | 37°F | 47.1°F | 2.20 | – | <1 | 11 | 11 h |
| November | 41°F | 23°F | 32.1°F | 0.78 | – | <1 | 23 | 9 h 30 min |
| December | 28°F | 11°F | 19.0°F | 0.81 | – | <1 | 31 | 8 h 50 min |
| Year (annual) | 54°F | 34°F | 44.2°F | 23.98 | – | 11 | 165 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | −6°C | −15°C | −10.6°C | 14 mm |
| February | −3°C | −13°C | −7.8°C | 14 mm |
| March | 5°C | −6°C | −0.6°C | 23 mm |
| April | 13°C | 1°C | 6.9°C | 51 mm |
| May | 20°C | 8°C | 13.9°C | 81 mm |
| June | 25°C | 13°C | 19.3°C | 100 mm |
| July | 28°C | 16°C | 21.9°C | 97 mm |
| August | 27°C | 15°C | 21.0°C | 70 mm |
| September | 23°C | 10°C | 16.3°C | 63 mm |
| October | 14°C | 3°C | 8.4°C | 56 mm |
| November | 5°C | −5°C | 0.1°C | 20 mm |
| December | −2°C | −12°C | −7.2°C | 21 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Webster (19 miles away), gets 43 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00390120; 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 Andover?
Normal highs sit between 65°F and 85°F in May, June, July, August and September.
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 USC00390120.
When is the last frost in Andover?
In Andover, the last spring frost (32°F) comes after May 6 in half of years and after May 21 in one year in ten; the first autumn frost comes before October 4 in half of years and before September 21 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 61 year in 10 after May 21; 9 in 10 after April 22
- First autumn frost, half of years before
- October 41 year in 10 before September 21; 9 in 10 before October 19
NOAA puts the median frost-free season at 150 days, and the season without a hard freeze (28°F) at 168 days.
A hard freeze (28°F) comes after April 28 in half of springs and before October 14 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Andover in zone 4b in ZIP code 57422, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Andover's NOAA station is in zone 4a: the coldest night of a typical year reaches −26°F (15 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 USC00390120; 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 Andover?
In a normal year in Andover, 11 days a year reach 90°F and 165 nights fall to 32°F or colder.
- Days at 90°F or more
- 11a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 165a normal year
- Days that stay below freezing
- 79high of 32°F or less
Source: NOAA NCEI 1991-2020 annual normals, station USC00390120.
How sunny is Andover?
Over a year 76% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Andover, 4.0 kWh per square metre a day. July is the sunniest month (83%) and December the cloudiest (65%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 78% | 1.9 |
| February | 82% | 3.0 |
| March | 73% | 3.9 |
| April | 72% | 4.9 |
| May | 71% | 5.6 |
| June | 76% | 6.3 |
| July | 83% | 6.6 |
| August | 81% | 5.5 |
| September | 78% | 4.2 |
| October | 70% | 2.7 |
| November | 70% | 1.8 |
| December | 65% | 1.3 |
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 Andover need?
A normal year in Andover brings 8,121 heating degree days, 51% more than the median U.S. place (5,373), and 593 cooling degree days, 35% fewer 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 2,564 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,610 | 0 |
| February | 1,320 | 0 |
| March | 1,059 | 0 |
| April | 620 | 1 |
| May | 276 | 28 |
| June | 58 | 110 |
| July | 15 | 216 |
| August | 24 | 172 |
| September | 168 | 60 |
| October | 560 | 5 |
| November | 987 | 0 |
| December | 1,424 | 0 |
| Year (annual) | 8,121 | 593 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00390120. 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 Andover been warmer than normal lately?
2025 averaged 46.0°F, 1.8°F above the 1991-2020 normal of 44.2°F. 4 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 47.6°F | +3.4°F | 22.35 |
| 2022 | 43.1°F | −1.1°F | – |
| 2023 | 45.3°F | +1.1°F | 24.24 |
| 2024 | 47.2°F | +3.0°F | 18.21 |
| 2025 | 46.0°F | +1.8°F | 26.75 |
Source: observed years: ACIS, station USC00390120. A year counts only with all twelve months complete.
How does Andover's climate compare?
Andover is warmer than 29 of the other 99 places with their own NOAA record in South Dakota, and wetter than 59. Across the 7,247 U.S. stations with normals, its annual mean of 44.2°F is warmer than 16%.
In the Köppen classification computed from these normals, Andover is Dfb: continental, no dry season, warm 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 Andover 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.
- Groton, SD1,343 people · 10 mi W
- Bristol, SD275 people · 9 mi SE
- Pierpont, SD121 people · 7 mi NE
- Ferney, SD1 people · 11 mi SW
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 Andover's climate
What is the coldest month in Andover?
January, with a normal high of 22°F and a normal low of 5°F. The warmest is July (82°F by day, 61°F at night).
Does it snow in Andover?
Yes. NOAA publishes no 1991-2020 snowfall normal for Andover's NOAA station; the nearest record that keeps one, Webster (19 miles away), records 43 inches of snow in a normal year.
What is the rainiest month in Andover?
June, with 3.92 in of precipitation in a normal year; the driest is January with 0.57 in.
What plant hardiness zone is Andover in?
The USDA's 2023 map puts Andover in zone 4b in ZIP code 57422, the nearest ZIP area. By the same method at Andover's NOAA station, the coldest night of a typical year reaches −26°F (15 years, 1991-2020): zone 4a.
How late can frost come in Andover?
In half of years the last 32°F night comes after May 6; 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
- Webster, SD19 miles from this station, 42.7°F a year
- Conde, SD21 miles from this station, 43.6°F a year
- Aberdeen, SD25 miles from this station, 44.1°F a year
- Turton, SD27 miles from this station, 44.2°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made