Ice dam risk in Grass Valley, CA
Will your roof get ice dams in Grass Valley, CA?
0.2 dam days a winter
Almost never. An ordinary house in Grass Valley sees 0.2 days a winter when an ice dam can form, because snow rarely stays on a roof long enough below freezing.
Grass Valley averages 9 inches of snow a year and about 2 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 Grass Valley?
- 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.
Grass Valley winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 0.7 | 0.1 | 0.0 |
| February | 3.0 | 0.8 | 0.1 |
| March | 3.0 | 0.6 | 0.0 |
| April | 0.5 | 0.1 | 0.0 |
| November | 0.2 | 0.0 | 0.0 |
| December | 1.2 | 0.4 | 0.1 |
Grass Valley next to nearby towns
Grass Valley ranks 5 of 376 California cities here for ice-dam days, behind Truckee at 36.3 days.
- Auburn, CA 23 mi, 0.0 days
- Lincoln, CA 27 mi, 0.0 days
- Marysville, CA 29 mi, 0.0 days
- Rocklin, CA 30 mi, 0.0 days
- Yuba City, CA 32 mi, 0.0 days
Where these numbers come from
NOAA 1991–2020 climate normals from Grass Valley #2, 1.4 miles from Grass Valley. 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.