Will Pipes Freeze in Union County, NJ? 35 nights a Year
Freeze nights in Union County
In a normal year Union County, NJ gets 35 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 50% 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 | 111 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 35 nights |
| Insulated pipe in unheated space | 10°F | 7 nights |
| Inside the heated house | 0°F | under 1 night |
Foam-sleeving a bare pipe in unheated space takes it from 35 nights of risk to 7 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 10/31, last around 04/11. For 20°F: 12/11 to 03/07.
How cold Union County nights get
Average winter (Dec-Feb) low: 27°F; the coldest month, January, averages 25°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, March, December: 7 nights a year, and under 1 night below zero.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 25°F | 27°F | 33°F | 43°F | 52°F | 62°F | 68°F | 66°F | 59°F | 47°F | 37°F | 30°F |
Union County next to its neighbours
Essex County, NJ, 15 km north, gets 38 nights below 20°F to Union County's 35 nights. Richmond County, NY, 18 km southeast, gets 22 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Union County, NJ | - | 111 nights | 35 nights | 25°F |
| Essex County, NJ | 15 km north | 117 nights | 38 nights | 22°F |
| Richmond County, NY | 18 km southeast | 82 nights | 22 nights | 26°F |
| Hudson County, NJ | 21 km east | 80 nights | 20 nights | 26°F |
| Middlesex County, NJ | 26 km south | 110 nights | 32 nights | 23°F |
| Somerset County, NJ | 28 km west | 129 nights | 43 nights | 20°F |
| Morris County, NJ | 30 km northwest | 131 nights | 48 nights | 19°F |
Union County within NJ
Union County ranks 8 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 66 ft, Union 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.
Why 20°F is the line for a garage pipe: how cold before pipes freeze.
Where this comes from
NOAA 1991-2020 climate normals, blended from 3 nearby stations and adjusted for elevation; closest is Cranford, NJ, 2 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.