Will Pipes Freeze in Mercer County, NJ? 31 nights a Year
Freeze nights in Mercer County
In a normal year Mercer County, NJ gets 31 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 47% of US counties.
Risk level: Regular. 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 | 107 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 31 nights |
| Insulated pipe in unheated space | 10°F | 6 nights |
| Inside the heated house | 0°F | under 1 night |
Foam-sleeving a bare pipe in unheated space takes it from 31 nights of risk to 6 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 10/28, last around 04/17. For 20°F: 12/01 to 03/10.
How cold Mercer County nights get
Average winter (Dec-Feb) low: 25°F; the coldest month, January, averages 23°F overnight. 7 months normally bring at least one night below 32°F (Jan, Feb, Mar, Apr, Oct, Nov, Dec). Nights below 10°F, cold enough to freeze insulated pipe in an unheated space, come in January, February, December: 6 nights a year, and under 1 night below zero.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 23°F | 24°F | 31°F | 41°F | 50°F | 59°F | 65°F | 63°F | 56°F | 44°F | 35°F | 27°F |
Mercer County next to its neighbours
Middlesex County, NJ, 31 km northeast, gets 32 nights below 20°F to Mercer County's 31 nights. Burlington County, NJ, 45 km south, gets 30 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Mercer County, NJ | - | 107 nights | 31 nights | 23°F |
| Middlesex County, NJ | 31 km northeast | 110 nights | 32 nights | 23°F |
| Somerset County, NJ | 32 km north | 129 nights | 43 nights | 20°F |
| Bucks County, PA | 35 km west | 106 nights | 32 nights | 23°F |
| Hunterdon County, NJ | 36 km northwest | 125 nights | 42 nights | 21°F |
| Burlington County, NJ | 45 km south | 108 nights | 30 nights | 24°F |
| Monmouth County, NJ | 47 km east | 102 nights | 28 nights | 24°F |
Mercer County within NJ
Mercer County ranks 11 of 21 NJ counties for nights below 20°F. The most is Sussex County, NJ at 58 nights, with a 20°F average winter low. The fewest is Hudson County, NJ: 20 nights, winter lows near 28°F. At 61 ft, Mercer County sits close to the state's median county elevation of 89 ft.
What to do here
- Insulate every pipe in unheated space before the season starts.
- Heat tape on the runs you cannot insulate well.
- Shut off and drain outdoor spigots for the season.
When to have the house ready: when freeze season starts.
Where this comes from
NOAA 1991-2020 climate normals, blended from 3 nearby stations and adjusted for elevation; closest is Trenton State College, NJ, 8 km away (close 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.