Will Pipes Freeze in Jefferson County, AL? 7 nights a Year
Freeze nights in Jefferson County
In a normal year Jefferson County, AL gets 7 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 22% of US counties.
Risk level: Occasional. The risk season runs December to February, worst in January.
It depends where the pipe is
| Pipe | Freezes near | Nights a year |
|---|---|---|
| Outdoor spigot, open crawlspace | 32°F | 54 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 7 nights |
| Insulated pipe in unheated space | 10°F | under 1 night |
| Inside the heated house | 0°F | none |
Foam-sleeving a bare pipe in unheated space takes it from 7 nights of risk to under 1 night. 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 11/11, last around 03/21. For 20°F: 01/01 to 02/04.
How cold Jefferson County nights get
Average winter (Dec-Feb) low: 36°F; the coldest month, January, averages 34°F overnight. 7 months normally bring at least one night below 32°F (Jan, Feb, Mar, Apr, Oct, Nov, Dec).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 34°F | 37°F | 44°F | 51°F | 60°F | 67°F | 71°F | 70°F | 64°F | 53°F | 42°F | 37°F |
Jefferson County next to its neighbours
Walker County, AL, 46 km northwest, gets 12 nights below 20°F to Jefferson County's 7 nights. Shelby County, AL, 39 km southeast, gets 5 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Jefferson County, AL | - | 54 nights | 7 nights | 34°F |
| Shelby County, AL | 39 km southeast | 46 nights | 5 nights | 35°F |
| Walker County, AL | 46 km northwest | 73 nights | 12 nights | 31°F |
| Blount County, AL | 56 km northeast | 70 nights | 11 nights | 31°F |
| St. Clair County, AL | 57 km east | 65 nights | 10 nights | 33°F |
| Bibb County, AL | 64 km south | 60 nights | 8 nights | 33°F |
| Cullman County, AL | 64 km north | 72 nights | 13 nights | 31°F |
Jefferson County within AL
Jefferson County ranks 28 of 67 AL counties for nights below 20°F. The most is Marion County, AL at 23 nights, with a 31°F average winter low. The fewest is Mobile County, AL: under 1 night, winter lows near 43°F. At 571 ft, Jefferson County sits 136 ft above the state's median county elevation of 435 ft.
What to do here
- Keep a night-of routine: drip, open cabinets, keep the heat at 55F or above.
- Foam-sleeve any pipe in the garage or crawlspace once; it is cheap and lasts years.
Which pipe gets which threshold: the 32, 20, 10 and 0 rule.
Where this comes from
NOAA 1991-2020 climate normals, blended from 3 nearby stations and adjusted for elevation; closest is Birmingham Airport, AL, 14 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.