Photo: GregGilbertson · CC BY-SA 3.0Hardly any U.S. towns see harsher January nights than Andover Township
July afternoons average 83°. Precipitation is light here, less than falls on 88% of U.S. towns. Since 1901–2000, the year has warmed by 1.3°, most of all in January. Comfortable outdoor weather lasts from May to September, with highs of 68–83°.
A year in Andover Township at a glance
Each month’s typical high and low, and what it brings.
What stands out about Andover Township’s climate
Compared with towns across the U.S., with Andover Township’s place in South Dakota beside it.
What a year in Andover Township feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 150 frost-free days a year
In half of years the last 32° night comes by May 6 and the first by October 4. Frost and day counts come from NOAA’s station at Andover #2, SD, 0.6 miles from the town’s center, at about the same height.
The 2023 USDA map puts Andover Township’s center in zone 4b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −25°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 32 inches of snow a winter
Snow, measured at Groton, SD, falls mostly in December. Precipitation (rain plus melted snow) adds up to 23 inches a year; June is the wettest month and January the driest. Rain or snow falls on about 71 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Andover Township
93% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through April.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Andover #2, SD.
Living with Andover Township’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
150 frost-free days in zone 4b. The last frost comes by May 6 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Oct 4.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September. 2.7 miles of trails are waiting.
Parks & trails →Cold waves are 33% of the yearly building losses FEMA expects in Andover Township from natural hazards, the largest share. Normals are averages; the hazards page covers the extremes.
Natural hazards →Andover Township and its neighbors
Every town next door is within a degree of Andover Township in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Andover Township’s, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Andover Township, SD | 3° | 83° | 23" | 32" |
| Litchfield, MN | 4° | 82° | 28" | 41" |
| Dickinson, ND | 5° | 83° | 16" | 35" |
| Sheldon, IA | 7° | 84° | 30" | 41" |
| Sidney, MT | 4° | 85° | 15" | 30" |
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
Warmer than it used to be
The last 30 years in Andover Township averaged 1.3° warmer than the 1900s. The biggest change is in January (+3.4°).
A smaller shift than in 57% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Andover Township compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Andover Township’s place among South Dakota’s.
Andover Township weather by month
Highs, lows and precipitation from NOAA’s grid at Andover Township’s center; snow, wet days and snow on the ground from Groton, SD. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 21° | 3° | 0.6" | 4.7" | 5 | −1° – 25° |
| February | 26° | 7° | 0.6" | 5.8" | 5 | 1° – 29° |
| March | 39° | 20° | 0.9" | 6.7" | 5 | 19° – 44° |
| April | 55° | 32° | 2.0" | 4.5" | 6 | 33° – 51° |
| May | 68° | 45° | 3.0" | 0.0" | 8 | 52° – 63° |
| June | 78° | 56° | 3.9" | 0.0" | 9 | 61° – 71° |
| July | 83° | 60° | 3.6" | 0.0" | 6 | 63° – 77° |
| August | 81° | 58° | 2.5" | 0.0" | 6 | 64° – 73° |
| September | 72° | 48° | 2.3" | 0.0" | 7 | 54° – 65° |
| October | 57° | 35° | 2.1" | 0.5" | 5 | 38° – 51° |
| November | 40° | 21° | 0.7" | 2.0" | 4 | 18° – 42° |
| December | 26° | 9° | 0.6" | 8.1" | 6 | 4° – 26° |
| Year | 54° | 33° | 22.7" | 32.3" | 71 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 1° to 29°. August is the most reliable, staying within 9°.
Where Andover Township’s numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Andover Township’s center.
- Snow: Groton, SD.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Andover #2, SD, 0.6 miles from the town’s center, at about the same height; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Andover Township’s climate
What is the weather like in Andover Township?
A typical July afternoon reaches 83°, a January night drops to 3°, and about 32 inches of snow falls in a normal winter. Colder January nights than all but 88 U.S. towns; cooler July afternoons than 76% of U.S. towns.
How cold does it get in Andover Township in winter?
January nights average 3°. About 165 nights a year reach 32° or below and 33 reach 0° or below. In the coldest January of the last 30 years the month averaged −1°.
How much snow does Andover Township get?
About 32 inches in a normal winter at Groton, SD, most of it in December.
How hot does it get in Andover Township?
July, with a typical high of 83° and a low of 60°. About 11 days a year reach 90° (Andover #2, SD).
When is the first and last frost in Andover Township?
In half of years the last spring frost (32°) comes by May 6 and the first fall frost by October 4, about 150 frost-free days, at Andover #2, SD.
What growing zone is Andover Township in?
Zone 4b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −25°.
What is the best time of year to visit Andover Township?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, July, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Andover Township getting warmer?
Yes: 1991–2020 averaged 1.3° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 57% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Andover Township.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.