Will Pipes Freeze in San Juan County, NM? 48 nights a Year
Freeze nights in San Juan County
In a normal year San Juan County, NM gets 48 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 63% of US counties.
Risk level: Severe. The risk season runs November to March, worst in January.
It depends where the pipe is
| Pipe | Freezes near | Nights a year |
|---|---|---|
| Outdoor spigot, open crawlspace | 32°F | 141 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 48 nights |
| Insulated pipe in unheated space | 10°F | 9 nights |
| Inside the heated house | 0°F | under 1 night |
Foam-sleeving a bare pipe in unheated space takes it from 48 nights of risk to 9 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 10/15, last around 04/29. For 20°F: 11/15 to 03/11.
How cold San Juan County nights get
Average winter (Dec-Feb) low: 22°F; the coldest month, January, averages 20°F overnight. 8 months normally bring at least one night below 32°F (Jan, Feb, Mar, Apr, May, Oct, Nov, Dec). Nights below 10°F, cold enough to freeze insulated pipe in an unheated space, come in January, February, December: 9 nights a year, and under 1 night below zero.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 20°F | 24°F | 30°F | 36°F | 45°F | 54°F | 61°F | 60°F | 52°F | 40°F | 28°F | 21°F |
San Juan County next to its neighbours
Montezuma County, CO, 95 km north, gets 68 nights below 20°F to San Juan County's 48 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| San Juan County, NM | - | 141 nights | 48 nights | 20°F |
| Montezuma County, CO | 95 km north | 168 nights | 68 nights | 17°F |
| La Plata County, CO | 96 km northeast | 187 nights | 85 nights | 12°F |
| McKinley County, NM | 103 km south | 206 nights | 109 nights | 13°F |
| Dolores County, CO | 137 km north | 164 nights | 70 nights | 17°F |
| Archuleta County, CO | 137 km northeast | 208 nights | 107 nights | 9°F |
| Rio Arriba County, NM | 146 km east | 217 nights | 118 nights | 9°F |
San Juan County within NM
San Juan County ranks 15 of 33 NM counties for nights below 20°F. The most is Rio Arriba County, NM at 118 nights, with a 11°F average winter low. The fewest is Sierra County, NM: 6 nights, winter lows near 31°F. At 6,082 ft, San Juan County sits 477 ft above the state's median county elevation of 5,604 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 Farmington Ag Sci Cnt, NM, 20 km away (fair 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.