Will Pipes Freeze in Bon Homme County, SD? 84 nights a Year
Freeze nights in Bon Homme County
In a normal year Bon Homme County, SD gets 84 nights at or below 20°F, the point where bare pipes in a garage, attic or outside wall start to freeze. That is more than 84% of US counties.
Risk level: Severe. The risk season runs October to April, worst in January.
It depends where the pipe is
| Pipe | Freezes near | Nights a year |
|---|---|---|
| Outdoor spigot, open crawlspace | 32°F | 157 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 84 nights |
| Insulated pipe in unheated space | 10°F | 43 nights |
| Inside the heated house | 0°F | 19 nights |
Foam-sleeving a bare pipe in unheated space takes it from 84 nights of risk to 43 nights. A 12 ft heat-tape kit runs $17 to $37; an average burst-pipe repair is about $500.
Month by month
Nights at or below 20°F in a normal year.
First 32°F night is usually around 10/07, last around 05/01. For 20°F: 11/04 to 04/03.
How cold Bon Homme County nights get
Average winter (Dec-Feb) low: 12°F; the coldest month, January, averages 9°F overnight. 8 months normally bring at least one night below 32°F (Jan, Feb, Mar, Apr, May, Oct, Nov, Dec). Nights below 10°F, cold enough to freeze insulated pipe in an unheated space, come in January, February, March, November, December: 43 nights a year, and 19 nights below zero.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 9°F | 13°F | 23°F | 34°F | 47°F | 58°F | 63°F | 60°F | 51°F | 37°F | 24°F | 14°F |
Bon Homme County next to its neighbours
Hutchinson County, SD, 41 km north, gets 85 nights below 20°F to Bon Homme County's 84 nights. Knox County, NE, 39 km south, gets 79 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Bon Homme County, SD | - | 157 nights | 84 nights | 9°F |
| Knox County, NE | 39 km south | 154 nights | 79 nights | 11°F |
| Yankton County, SD | 40 km east | 156 nights | 84 nights | 10°F |
| Hutchinson County, SD | 41 km north | 157 nights | 85 nights | 9°F |
| Douglas County, SD | 59 km northwest | 155 nights | 80 nights | 10°F |
| Charles Mix County, SD | 63 km northwest | 155 nights | 79 nights | 11°F |
| Cedar County, NE | 66 km southeast | 154 nights | 80 nights | 10°F |
Bon Homme County within SD
Bon Homme County ranks 60 of 66 SD counties for nights below 20°F. The most is Codington County, SD at 113 nights, with a 6°F average winter low. The fewest is Tripp County, SD: 75 nights, winter lows near 15°F. At 1,417 ft, Bon Homme County sits 368 ft below the state's median county elevation of 1,785 ft.
What to do here
- Treat it as a building fix, not a night-of routine: insulate, heat tape, seal crawlspace vents.
- An automatic leak shutoff pays for itself if one burst is avoided.
- Know where the main shutoff is before the first hard freeze.
The dates to be done by: when freeze season starts and ends.
Where this comes from
NOAA 1991-2020 climate normals, blended from 3 nearby stations and adjusted for elevation; closest is Tyndall, SD, 1 km away (close match). A normal year, not tonight's forecast: check the forecast low for the night itself. Why elevation is part of the blend: how county numbers are made.