Will Pipes Freeze in McCook County, SD? 99 nights a Year
Freeze nights in McCook County
In a normal year McCook County, SD gets 99 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 91% 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 | 167 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 99 nights |
| Insulated pipe in unheated space | 10°F | 57 nights |
| Inside the heated house | 0°F | 29 nights |
Foam-sleeving a bare pipe in unheated space takes it from 99 nights of risk to 57 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 09/29, last around 05/07. For 20°F: 10/28 to 04/09.
How cold McCook County nights get
Average winter (Dec-Feb) low: 9°F; the coldest month, January, averages 6°F overnight. 9 months normally bring at least one night below 32°F (Jan, Feb, Mar, Apr, May, Sep, Oct, Nov, Dec). Nights below 10°F, cold enough to freeze insulated pipe in an unheated space, come in January, February, March, November, December: 57 nights a year, and 29 nights below zero.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 6°F | 10°F | 21°F | 32°F | 45°F | 56°F | 61°F | 58°F | 49°F | 35°F | 21°F | 11°F |
McCook County next to its neighbours
Hanson County, SD, 35 km west, gets 87 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| McCook County, SD | - | 167 nights | 99 nights | 6°F |
| Hanson County, SD | 35 km west | 159 nights | 87 nights | 6°F |
| Miner County, SD | 43 km northwest | 169 nights | 98 nights | 5°F |
| Lake County, SD | 43 km northeast | 167 nights | 96 nights | 6°F |
| Turner County, SD | 45 km south | 160 nights | 88 nights | 8°F |
| Minnehaha County, SD | 45 km east | 159 nights | 89 nights | 8°F |
| Hutchinson County, SD | 50 km southwest | 157 nights | 85 nights | 9°F |
McCook County within SD
McCook County ranks 26 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 1,516 ft, McCook County sits 269 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 Salem (5 mi NE), SD, 8 km away (close match). A normal year, not tonight's forecast: check the forecast low for the night itself. What a "fair" or "distant" station match means is in the method guide.