Ice dam risk in Tacoma, WA
Will your roof get ice dams in Tacoma, WA?
0.5 dam days a winter
Almost never. An ordinary house in Tacoma sees 0.5 days a winter when an ice dam can form, because snow rarely stays on a roof long enough below freezing.
Tacoma averages 6 inches of snow a year and about 5 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 Tacoma?
- 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.
Tacoma winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 1.5 | 1.5 | 0.2 |
| February | 0.5 | 0.4 | 0.0 |
| March | 0.6 | 0.5 | 0.0 |
| November | 1.5 | 1.0 | 0.1 |
| December | 1.5 | 1.6 | 0.2 |
Tacoma next to nearby towns
Tacoma ranks 17 of 91 Washington cities here for ice-dam days, behind Spokane at 13.0 days.
- University Place, WA 5 mi, 0.5 days
- Fife, WA 5 mi, 0.5 days
- Lakewood, WA 7 mi, 0.5 days
- Federal Way, WA 7 mi, 0.2 days
- Edgewood, WA 8 mi, 0.5 days
Where these numbers come from
NOAA 1991–2020 climate normals from Mcmillin Rsvr, 12.5 miles from Tacoma. 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.