Will Pipes Freeze in Powder River County, MT? 97 nights a Year
Freeze nights in Powder River County
In a normal year Powder River County, MT gets 97 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 December.
It depends where the pipe is
| Pipe | Freezes near | Nights a year |
|---|---|---|
| Outdoor spigot, open crawlspace | 32°F | 186 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 97 nights |
| Insulated pipe in unheated space | 10°F | 48 nights |
| Inside the heated house | 0°F | 22 nights |
Foam-sleeving a bare pipe in unheated space takes it from 97 nights of risk to 48 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 09/19, last around 05/25. For 20°F: 10/16 to 04/22.
How cold Powder River County nights get
Average winter (Dec-Feb) low: 12°F; the coldest month, January, averages 11°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: 48 nights a year, and 22 nights below zero.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 11°F | 13°F | 22°F | 30°F | 40°F | 49°F | 56°F | 53°F | 44°F | 32°F | 20°F | 12°F |
Powder River County next to its neighbours
Carter County, MT, 82 km east, gets 104 nights below 20°F to Powder River County's 97 nights. Crook County, WY, 120 km southeast, gets 96 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Powder River County, MT | - | 186 nights | 97 nights | 11°F |
| Carter County, MT | 82 km east | 184 nights | 104 nights | 7°F |
| Custer County, MT | 95 km north | 180 nights | 97 nights | 8°F |
| Crook County, WY | 120 km southeast | 186 nights | 96 nights | 12°F |
| Rosebud County, MT | 121 km northwest | 172 nights | 84 nights | 11°F |
| Sheridan County, WY | 125 km southwest | 185 nights | 93 nights | 13°F |
| Fallon County, MT | 135 km northeast | 185 nights | 103 nights | 7°F |
Powder River County within MT
Powder River County ranks 27 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 3,935 ft, Powder River County sits close to 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 Sonnette (7 mi SW), MT, 30 km away (fair 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.