Will Pipes Freeze in Boise County, ID? 101 nights a Year
Freeze nights in Boise County
In a normal year Boise County, ID gets 101 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 92% of US counties.
Risk level: Severe. The risk season runs October to May, worst in January.
It depends where the pipe is
| Pipe | Freezes near | Nights a year |
|---|---|---|
| Outdoor spigot, open crawlspace | 32°F | 238 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 101 nights |
| Insulated pipe in unheated space | 10°F | 49 nights |
| Inside the heated house | 0°F | 21 nights |
Foam-sleeving a bare pipe in unheated space takes it from 101 nights of risk to 49 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.
How cold Boise County nights get
Average winter (Dec-Feb) low: 13°F; the coldest month, January, averages 12°F overnight. 12 months normally bring at least one night below 32°F (Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec). Nights below 10°F, cold enough to freeze insulated pipe in an unheated space, come in January, February, March, April, November, December: 49 nights a year, and 21 nights below zero.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 12°F | 15°F | 21°F | 26°F | 33°F | 38°F | 43°F | 41°F | 34°F | 27°F | 19°F | 12°F |
Boise County next to its neighbours
Elmore County, ID, 69 km south, gets 106 nights below 20°F to Boise County's 101 nights. Gem County, ID, 55 km west, gets 51 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Boise County, ID | - | 238 nights | 101 nights | 12°F |
| Gem County, ID | 55 km west | 157 nights | 51 nights | 20°F |
| Elmore County, ID | 69 km south | 211 nights | 106 nights | 10°F |
| Ada County, ID | 73 km southwest | 117 nights | 29 nights | 26°F |
| Payette County, ID | 83 km west | 138 nights | 35 nights | 23°F |
| Canyon County, ID | 89 km southwest | 117 nights | 27 nights | 24°F |
| Camas County, ID | 93 km southeast | 233 nights | 126 nights | 8°F |
Boise County within ID
Boise County ranks 13 of 44 ID counties for nights below 20°F. The most is Custer County, ID at 145 nights, with a 5°F average winter low. The fewest is Nez Perce County, ID: 20 nights, winter lows near 27°F. At 7,104 ft, Boise County sits 2,458 ft above the state's median county elevation of 4,646 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 Deadwood Lodge, ID, 54 km away (distant 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.