Will Pipes Freeze in Brown County, IL? 49 nights a Year
Freeze nights in Brown County
In a normal year Brown County, IL gets 49 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 63% 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 | 124 nights |
| Bare pipe in garage, attic or outside wall | 20°F | 49 nights |
| Insulated pipe in unheated space | 10°F | 21 nights |
| Inside the heated house | 0°F | 7 nights |
Foam-sleeving a bare pipe in unheated space takes it from 49 nights of risk to 21 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 10/15, last around 04/18. For 20°F: 11/17 to 03/17.
How cold Brown County nights get
Average winter (Dec-Feb) low: 20°F; the coldest month, January, averages 17°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: 21 nights a year, and 7 nights below zero.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 17°F | 21°F | 31°F | 41°F | 53°F | 62°F | 65°F | 63°F | 55°F | 43°F | 32°F | 23°F |
Brown County next to its neighbours
Scott County, IL, 43 km southeast, gets 50 nights below 20°F to Brown County's 49 nights. Adams County, IL, 38 km west, gets 44 nights.
| County | Distance | Below 32°F | Below 20°F | Jan low |
|---|---|---|---|---|
| Brown County, IL | - | 124 nights | 49 nights | 17°F |
| Schuyler County, IL | 25 km northeast | 121 nights | 49 nights | 17°F |
| Adams County, IL | 38 km west | 113 nights | 44 nights | 18°F |
| Pike County, IL | 39 km south | 119 nights | 46 nights | 19°F |
| Scott County, IL | 43 km southeast | 122 nights | 50 nights | 18°F |
| Cass County, IL | 43 km east | 124 nights | 49 nights | 18°F |
| Morgan County, IL | 54 km southeast | 125 nights | 49 nights | 18°F |
Brown County within IL
Brown County ranks 42 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 705 ft, Brown County sits 73 ft above 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 Perry (6 mi NW), IL, 19 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.