PipeFreezeNights

Will Pipes Freeze in Loudoun County, VA? 31 nights a Year

Freeze nights in Loudoun County

In a normal year Loudoun County, VA 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

PipeFreezes nearNights a year
Outdoor spigot, open crawlspace32°F114 nights
Bare pipe in garage, attic or outside wall20°F31 nights
Insulated pipe in unheated space10°F6 nights
Inside the heated house0°Funder 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.

  1. Jul
  2. Aug
  3. Sep
  4. Oct
  5. 2Nov
  6. 7Dec
  7. 11Jan
  8. 8Feb
  9. 3Mar
  10. Apr
  11. May
  12. Jun

First 32°F night is usually around 10/25, last around 04/16. For 20°F: 12/01 to 03/10.

How cold Loudoun County nights get

Average winter (Dec-Feb) low: 26°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, December: 6 nights a year, and under 1 night below zero.

JanFebMarAprMayJunJulAugSepOctNovDec
25°F26°F33°F43°F52°F61°F66°F64°F57°F45°F35°F29°F

Loudoun County next to its neighbours

Clarke County, VA, 31 km west, gets 36 nights below 20°F to Loudoun County's 31 nights. Montgomery County, MD, 38 km east, gets 21 nights.

CountyDistanceBelow 32°FBelow 20°FJan low
Loudoun County, VA-114 nights31 nights25°F
Clarke County, VA31 km west116 nights36 nights23°F
Jefferson County, WV32 km northwest114 nights34 nights23°F
Montgomery County, MD38 km east87 nights21 nights27°F
Manassas Park city, VA39 km southeast95 nights24 nights24°F
Fairfax city, VA39 km southeast100 nights24 nights24°F
Manassas city, VA40 km south94 nights24 nights24°F

Loudoun County within VA

Loudoun County ranks 38 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 681 ft, Loudoun County sits 234 ft above the state's median county elevation of 448 ft.

What to do here

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 Purcellville, VA, 9 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.