Ice dam risk in St. Helens, OR
How often ice dams form in St. Helens
0.2 dam days a winter
Almost never. An ordinary house in St. Helens sees 0.2 days a winter when an ice dam can form, because snow rarely stays on a roof long enough below freezing.
St. Helens averages 1 inch of snow a year and about 1 day 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 St. Helens?
- 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.
St. Helens winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 0.5 | 0.9 | 0.1 |
| February | 0.1 | 0.3 | 0.0 |
| December | 0.2 | 0.2 | 0.0 |
St. Helens next to nearby towns
St. Helens ranks 16 of 57 Oregon cities here for ice-dam days, behind Klamath Falls at 9.8 days.
- Ridgefield, WA 7 mi, 0.0 days
- Battle Ground, WA 14 mi, 0.0 days
- Kelso, WA 18 mi, 0.2 days
- Vancouver, WA 19 mi, 0.2 days
- Longview, WA 21 mi, 0.2 days
Where these numbers come from
NOAA 1991–2020 climate normals from Vancouver 4 NNE, 14.7 miles from St. Helens. 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.