Will Pipes Freeze in Prairie County, MT? 105 nights a Year
Freeze nights in Prairie County
In a normal year Prairie County, MT gets 105 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 94% 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 | 188 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 105 nights |
| Insulated pipe in unheated space | 10°F | 59 nights |
| Inside the heated house | 0°F | 32 nights |
Foam-sleeving a bare pipe in unheated space takes it from 105 nights of risk to 59 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 09/28, last around 05/12. For 20°F: 10/24 to 04/11.
How cold Prairie 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, April, October, November, December: 59 nights a year, and 32 nights below zero.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 6°F | 10°F | 21°F | 31°F | 41°F | 51°F | 57°F | 55°F | 44°F | 32°F | 20°F | 10°F |
Prairie County next to its neighbours
Custer County, MT, 61 km south, gets 97 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Prairie County, MT | - | 188 nights | 105 nights | 6°F |
| Custer County, MT | 61 km south | 180 nights | 97 nights | 8°F |
| Dawson County, MT | 68 km northeast | 175 nights | 94 nights | 8°F |
| McCone County, MT | 93 km north | 183 nights | 99 nights | 7°F |
| Wibaux County, MT | 95 km east | 189 nights | 104 nights | 6°F |
| Fallon County, MT | 100 km southeast | 185 nights | 103 nights | 7°F |
| Rosebud County, MT | 114 km southwest | 172 nights | 84 nights | 11°F |
Prairie County within MT
Prairie County ranks 14 of 56 MT counties for nights below 20°F. The most is Sheridan County, MT at 129 nights, with a 2°F average winter low. The fewest is Lake County, MT: 40 nights, winter lows near 22°F. At 2,554 ft, Prairie County sits 1,368 ft below the state's median county elevation of 3,922 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 Terry, MT, 16 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.