Ice dam risk in Napa, CA
Ice dams in Napa, CA: how often
0.0 dam days a winter
Almost never. An ordinary house in Napa sees 0.0 days a winter when an ice dam can form, because snow rarely stays on a roof long enough below freezing.
Napa averages 0 inches of snow a year and about 0 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 Napa?
- 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.
Napa next to nearby towns
Napa ranks 120 of 376 California cities here for ice-dam days, behind Truckee at 36.3 days.
- American Canyon, CA 9 mi, 0.0 days
- Sonoma, CA 9 mi, 0.0 days
- Vallejo, CA 13 mi, 0.0 days
- Fairfield, CA 15 mi, 0.0 days
- Suisun City, CA 16 mi, 0.0 days
Where these numbers come from
NOAA 1991–2020 climate normals from Napa State Hospital, 2.4 miles from Napa. 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.