Will Pipes Freeze in Mercer County, PA? 67 nights a Year
Freeze nights in Mercer County
In a normal year Mercer County, PA gets 67 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 75% of US counties.
Risk level: Severe. The risk season runs November to April, worst in January.
It depends where the pipe is
| Pipe | Freezes near | Nights a year |
|---|---|---|
| Outdoor spigot, open crawlspace | 32°F | 156 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 67 nights |
| Insulated pipe in unheated space | 10°F | 26 nights |
| Inside the heated house | 0°F | 8 nights |
Foam-sleeving a bare pipe in unheated space takes it from 67 nights of risk to 26 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 10/03, last around 05/15. For 20°F: 11/07 to 04/12.
How cold Mercer County nights get
Average winter (Dec-Feb) low: 18°F; the coldest month, January, averages 16°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, December: 26 nights a year, and 8 nights below zero.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 16°F | 17°F | 25°F | 34°F | 44°F | 53°F | 57°F | 56°F | 49°F | 38°F | 30°F | 22°F |
Mercer County next to its neighbours
Lawrence County, PA, 35 km south, gets 51 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Mercer County, PA | - | 156 nights | 67 nights | 16°F |
| Lawrence County, PA | 35 km south | 134 nights | 51 nights | 19°F |
| Venango County, PA | 42 km east | 146 nights | 58 nights | 18°F |
| Trumbull County, OH | 43 km west | 133 nights | 47 nights | 18°F |
| Crawford County, PA | 45 km north | 130 nights | 52 nights | 18°F |
| Butler County, PA | 51 km southeast | 139 nights | 54 nights | 17°F |
| Mahoning County, OH | 54 km southwest | 138 nights | 55 nights | 18°F |
Mercer County within PA
Mercer County ranks 11 of 67 PA counties for nights below 20°F. The most is Susquehanna County, PA at 80 nights, with a 15°F average winter low. The fewest is Delaware County, PA: 15 nights, winter lows near 28°F. At 1,303 ft, Mercer County sits 162 ft above the state's median county elevation of 1,141 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.
At this many nights, foam alone is not the answer: insulate or heat tape?.
Where this comes from
NOAA 1991-2020 climate normals, blended from 3 nearby stations and adjusted for elevation; closest is Mercer, PA, 9 km away (close 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.