Will Pipes Freeze in Santa Clara County, CA? under 1 night a Year
Freeze nights in Santa Clara County
In a normal year Santa Clara County, CA gets under 1 night at or below 20°F, the point where bare pipes in a garage, attic or outside wall start to freeze. That is more than 2% of US counties.
Risk level: Rare.
It depends where the pipe is
| Pipe | Freezes near | Nights a year |
|---|---|---|
| Outdoor spigot, open crawlspace | 32°F | 11 nights |
| Bare pipe in garage, attic or outside wall | 20°F | under 1 night |
| Insulated pipe in unheated space | 10°F | none |
| Inside the heated house | 0°F | none |
Month by month
Nights at or below 20°F in a normal year.
First 32°F night is usually around 12/06, last around 02/02.
How cold Santa Clara County nights get
Average winter (Dec-Feb) low: 41°F; the coldest month, December, averages 40°F overnight. 4 months normally bring at least one night below 32°F (Jan, Feb, Nov, Dec).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 40°F | 42°F | 44°F | 46°F | 50°F | 54°F | 56°F | 57°F | 55°F | 50°F | 44°F | 40°F |
Santa Clara County next to its neighbours
Merced County, CA, 86 km east, gets under 1 night below 20°F to Santa Clara County's under 1 night.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Santa Clara County, CA | - | 11 nights | under 1 night | 40°F |
| Santa Cruz County, CA | 37 km southwest | 20 nights | under 1 night | 40°F |
| Alameda County, CA | 51 km northwest | 14 nights | none | 39°F |
| San Mateo County, CA | 64 km west | 18 nights | none | 40°F |
| Stanislaus County, CA | 72 km northeast | 12 nights | none | 39°F |
| Contra Costa County, CA | 81 km north | 11 nights | none | 42°F |
| Merced County, CA | 86 km east | 33 nights | under 1 night | 37°F |
Santa Clara County within CA
Santa Clara County ranks 44 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 1,017 ft, Santa Clara County sits 281 ft below the state's median county elevation of 1,298 ft.
What to do here
- Watch the forecast for a sub-threshold night.
- That night: drip the faucet on an outside wall, open the sink cabinet.
A few nights a year catches houses that were never built for it: pipes in places that rarely freeze.
Where this comes from
NOAA 1991-2020 climate normals, blended from 3 nearby stations and adjusted for elevation; closest is Los Gatos, CA, 24 km away (fair match). A normal year, not tonight's forecast: check the forecast low for the night itself. How a county figure is built from stations: how the numbers are made.