Will Pipes Freeze in Harrison County, MO? 59 nights a Year
Freeze nights in Harrison County
In a normal year Harrison County, MO gets 59 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 71% of US counties.
Risk level: Severe. The risk season runs November to April, worst in January.
It depends where the pipe is
| Pipe | Freezes near | Nights a year |
|---|---|---|
| Outdoor spigot, open crawlspace | 32°F | 132 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 59 nights |
| Insulated pipe in unheated space | 10°F | 27 nights |
| Inside the heated house | 0°F | 9 nights |
Foam-sleeving a bare pipe in unheated space takes it from 59 nights of risk to 27 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 10/22, last around 04/16. For 20°F: 11/17 to 03/18.
How cold Harrison County nights get
Average winter (Dec-Feb) low: 19°F; the coldest month, January, averages 15°F overnight. 7 months normally bring at least one night below 32°F (Jan, Feb, Mar, Apr, Oct, Nov, Dec). Nights below 10°F, cold enough to freeze insulated pipe in an unheated space, come in January, February, March, November, December: 27 nights a year, and 9 nights below zero.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 15°F | 19°F | 30°F | 41°F | 51°F | 62°F | 66°F | 64°F | 55°F | 43°F | 31°F | 21°F |
Harrison County next to its neighbours
Gentry County, MO, 38 km southwest, gets 62 nights below 20°F to Harrison County's 59 nights. Mercer County, MO, 37 km east, gets 56 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Harrison County, MO | - | 132 nights | 59 nights | 15°F |
| Mercer County, MO | 37 km east | 127 nights | 56 nights | 15°F |
| Gentry County, MO | 38 km southwest | 133 nights | 62 nights | 15°F |
| Worth County, MO | 39 km northwest | 137 nights | 64 nights | 13°F |
| Daviess County, MO | 43 km south | 128 nights | 56 nights | 16°F |
| Grundy County, MO | 45 km southeast | 127 nights | 55 nights | 16°F |
| Decatur County, IA | 47 km north | 138 nights | 66 nights | 14°F |
Harrison County within MO
Harrison County ranks 8 of 115 MO counties for nights below 20°F. The most is Caldwell County, MO at 65 nights, with a 19°F average winter low. The fewest is Pemiscot County, MO: 14 nights, winter lows near 31°F. At 1,003 ft, Harrison County sits 161 ft above the state's median county elevation of 842 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.
Interior pipes have a threshold too: the four freeze points.
Where this comes from
NOAA 1991-2020 climate normals, blended from 3 nearby stations and adjusted for elevation; closest is Bethany, MO, 10 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.