Ice dam risk in Knoxville, TN
Ice dams in Knoxville, TN: how often
0.5 dam days a winter
Almost never. An ordinary house in Knoxville sees 0.5 days a winter when an ice dam can form, because snow rarely stays on a roof long enough below freezing.
Knoxville averages 5 inches of snow a year and about 3 days with snow on the ground. Too little lies on the roof for long. The conditions that make a dam need all three at once: snow, cold at the eave and heat above it.
Do you need to do anything in Knoxville?
- Nothing for ice dams. If you are buying here and an inspector mentions water at the eaves, ask what they saw: it is far more likely a gutter, flashing or drip-edge problem than ice.
Snowy places are not always the worst: why snowfall misleads.
Knoxville winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 1.7 | 1.7 | 0.3 |
| February | 1.4 | 0.8 | 0.1 |
| March | 0.9 | 0.3 | 0.0 |
| November | 0.1 | 0.1 | 0.0 |
| December | 0.5 | 0.4 | 0.1 |
Knoxville next to nearby towns
Knoxville ranks 18 of 65 Tennessee cities here for ice-dam days, behind Crossville at 2.6 days.
- Alcoa, TN 11 mi, 0.5 days
- Clinton, TN 13 mi, 0.6 days
- Farragut, TN 14 mi, 0.3 days
- Maryville, TN 15 mi, 0.5 days
- Oak Ridge, TN 19 mi, 0.6 days
Where these numbers come from
NOAA 1991–2020 climate normals from Knoxville Airport, 10.7 miles from Knoxville. A dam day is a day with snow on the roof and freezing at the eave while heat or sun melts the snow above it. This describes a normal winter, not this one.