Ice dam risk in San Dimas, CA
How often ice dams form in San Dimas
0.0 dam days a winter
Almost never. An ordinary house in San Dimas sees 0.0 days a winter when an ice dam can form, because snow rarely stays on a roof long enough below freezing.
San Dimas 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 San Dimas?
- 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.
San Dimas next to nearby towns
San Dimas ranks 231 of 376 California cities here for ice-dam days, behind Truckee at 36.3 days.
- La Verne, CA 2 mi, 0.0 days
- Glendora, CA 3 mi, 0.0 days
- Pomona, CA 4 mi, 0.0 days
- Covina, CA 4 mi, 0.0 days
- Claremont, CA 6 mi, 0.0 days
Where these numbers come from
NOAA 1991–2020 climate normals from Pomona/Fairplex, 3.0 miles from San Dimas. 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.