Will Pipes Freeze in Trinity County, CA? 5 nights a Year
Freeze nights in Trinity County
In a normal year Trinity County, CA gets 5 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 18% of US counties.
Risk level: Occasional. The risk season runs November to February, worst in January.
It depends where the pipe is
| Pipe | Freezes near | Nights a year |
|---|---|---|
| Outdoor spigot, open crawlspace | 32°F | 84 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 5 nights |
| Insulated pipe in unheated space | 10°F | under 1 night |
| Inside the heated house | 0°F | none |
Foam-sleeving a bare pipe in unheated space takes it from 5 nights of risk to under 1 night. 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 10/11, last around 05/03. For 20°F: 12/09 to 01/29.
How cold Trinity County nights get
Average winter (Dec-Feb) low: 33°F; the coldest month, December, averages 32°F overnight. 8 months normally bring at least one night below 32°F (Jan, Feb, Mar, Apr, May, Oct, Nov, Dec).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 33°F | 33°F | 35°F | 37°F | 43°F | 48°F | 53°F | 51°F | 45°F | 38°F | 35°F | 32°F |
Trinity County next to its neighbours
Siskiyou County, CA, 115 km northeast, gets 26 nights below 20°F to Trinity County's 5 nights. Humboldt County, CA, 69 km west, gets 1 night.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Trinity County, CA | - | 84 nights | 5 nights | 33°F |
| Humboldt County, CA | 69 km west | 29 nights | 1 night | 38°F |
| Shasta County, CA | 91 km east | 17 nights | under 1 night | 39°F |
| Tehama County, CA | 95 km southeast | 19 nights | under 1 night | 38°F |
| Siskiyou County, CA | 115 km northeast | 139 nights | 26 nights | 27°F |
| Glenn County, CA | 131 km southeast | 52 nights | 1 night | 35°F |
| Mendocino County, CA | 138 km south | 80 nights | 3 nights | 34°F |
Trinity County within CA
Trinity County ranks 12 of 58 CA counties for nights below 20°F. The most is Mono County, CA at 130 nights, with a 13°F average winter low. The fewest is Orange County, CA: none, winter lows near 46°F. At 5,070 ft, Trinity County sits 3,772 ft above the state's median county elevation of 1,298 ft.
What to do here
- Keep a night-of routine: drip, open cabinets, keep the heat at 55F or above.
- Foam-sleeve any pipe in the garage or crawlspace once; it is cheap and lasts years.
Which pipe gets which threshold: the 32, 20, 10 and 0 rule.
Where this comes from
NOAA 1991-2020 climate normals, blended from 3 nearby stations and adjusted for elevation; closest is Weaverville, CA, 18 km away (distant 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.