Will Pipes Freeze in Arlington County, VA? 18 nights a Year
Freeze nights in Arlington County
In a normal year Arlington County, VA gets 18 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 35% 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 | 83 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 18 nights |
| Insulated pipe in unheated space | 10°F | 2 nights |
| Inside the heated house | 0°F | none |
Foam-sleeving a bare pipe in unheated space takes it from 18 nights of risk to 2 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 04/09. For 20°F: 12/06 to 03/06.
How cold Arlington County nights get
Average winter (Dec-Feb) low: 29°F; the coldest month, January, averages 27°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: 2 nights a year, and none below zero.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 27°F | 29°F | 35°F | 45°F | 55°F | 64°F | 69°F | 68°F | 61°F | 49°F | 38°F | 31°F |
Arlington County next to its neighbours
Falls Church city, VA, 7 km west, gets 21 nights below 20°F to Arlington County's 18 nights. Alexandria city, VA, 7 km south, gets 15 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Arlington County, VA | - | 83 nights | 18 nights | 27°F |
| Falls Church city, VA | 7 km west | 92 nights | 21 nights | 25°F |
| Alexandria city, VA | 7 km south | 76 nights | 15 nights | 28°F |
| District of Columbia, DC | 8 km east | 80 nights | 16 nights | 28°F |
| Fairfax County, VA | 16 km west | 99 nights | 24 nights | 24°F |
| Fairfax city, VA | 17 km west | 100 nights | 24 nights | 24°F |
| Prince George's County, MD | 23 km east | 99 nights | 26 nights | 25°F |
Arlington County within VA
Arlington County ranks 85 of 133 VA counties for nights below 20°F. The most is Highland County, VA at 62 nights, with a 20°F average winter low. The fewest is Norfolk city, VA: 4 nights, winter lows near 35°F. At 265 ft, Arlington County sits 182 ft below the state's median county elevation of 448 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 Dalecarlia Rsvr, MD, 7 km away (close match). A normal year, not tonight's forecast: check the forecast low for the night itself. Why elevation is part of the blend: how county numbers are made.