Will Pipes Freeze in Shelby County, IL? 41 nights a Year
Freeze nights in Shelby County
In a normal year Shelby County, IL gets 41 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 56% of US counties.
Risk level: Severe. 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 | 113 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 41 nights |
| Insulated pipe in unheated space | 10°F | 16 nights |
| Inside the heated house | 0°F | 5 nights |
Foam-sleeving a bare pipe in unheated space takes it from 41 nights of risk to 16 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 10/24, last around 04/10. For 20°F: 11/26 to 03/11.
How cold Shelby County nights get
Average winter (Dec-Feb) low: 22°F; the coldest month, January, averages 19°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: 16 nights a year, and 5 nights below zero.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 19°F | 23°F | 32°F | 43°F | 54°F | 63°F | 67°F | 64°F | 57°F | 45°F | 34°F | 25°F |
Shelby County next to its neighbours
Moultrie County, IL, 32 km northeast, gets 46 nights below 20°F to Shelby County's 41 nights. Effingham County, IL, 41 km southeast, gets 40 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Shelby County, IL | - | 113 nights | 41 nights | 19°F |
| Moultrie County, IL | 32 km northeast | 119 nights | 46 nights | 19°F |
| Effingham County, IL | 41 km southeast | 112 nights | 40 nights | 20°F |
| Christian County, IL | 45 km northwest | 117 nights | 42 nights | 19°F |
| Fayette County, IL | 47 km southwest | 107 nights | 36 nights | 21°F |
| Cumberland County, IL | 50 km east | 113 nights | 38 nights | 20°F |
| Coles County, IL | 52 km east | 106 nights | 38 nights | 21°F |
Shelby County within IL
Shelby County ranks 60 of 102 IL counties for nights below 20°F. The most is Jo Daviess County, IL at 76 nights, with a 14°F average winter low. The fewest is Alexander County, IL: 21 nights, winter lows near 29°F. At 604 ft, Shelby County sits close to the state's median county elevation of 632 ft.
What to do here
- Treat it as a building fix, not a night-of routine: insulate, heat tape, seal crawlspace vents.
- An automatic leak shutoff pays for itself if one burst is avoided.
- Know where the main shutoff is before the first hard freeze.
At this many nights, foam alone is not the answer: insulate or heat tape?.
Where this comes from
NOAA 1991-2020 climate normals, blended from 3 nearby stations and adjusted for elevation; closest is Shelbyville Dam, IL, 3 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.