Will Pipes Freeze in Shelby County, AL? 5 nights a Year
Freeze nights in Shelby County
In a normal year Shelby County, AL gets 5 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 16% 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 | 46 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 5 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 5 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 11/16, last around 03/12. For 20°F: 01/04 to 01/24.
How cold Shelby County nights get
Average winter (Dec-Feb) low: 37°F; the coldest month, January, averages 35°F overnight. 5 months normally bring at least one night below 32°F (Jan, Feb, Mar, Nov, Dec).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 35°F | 39°F | 46°F | 52°F | 61°F | 68°F | 72°F | 71°F | 65°F | 53°F | 43°F | 38°F |
Shelby County next to its neighbours
Jefferson County, AL, 39 km northwest, gets 7 nights below 20°F to Shelby County's 5 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Shelby County, AL | - | 46 nights | 5 nights | 35°F |
| Jefferson County, AL | 39 km northwest | 54 nights | 7 nights | 34°F |
| Chilton County, AL | 46 km south | 50 nights | 6 nights | 34°F |
| Talladega County, AL | 46 km east | 70 nights | 11 nights | 31°F |
| Bibb County, AL | 52 km southwest | 60 nights | 8 nights | 33°F |
| Coosa County, AL | 54 km southeast | 52 nights | 7 nights | 34°F |
| St. Clair County, AL | 60 km northeast | 65 nights | 10 nights | 33°F |
Shelby County within AL
Shelby County ranks 42 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 644 ft, Shelby County sits 209 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.
Whether foam sleeves are enough here: insulate or heat tape?.
Where this comes from
NOAA 1991-2020 climate normals, blended from 3 nearby stations and adjusted for elevation; closest is Alabaster Shelby County Airport, AL, 15 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.