Ice dam risk in Danville, CA
How often ice dams form in Danville
0.0 dam days a winter
Almost never. An ordinary house in Danville sees 0.0 days a winter when an ice dam can form, because snow rarely stays on a roof long enough below freezing.
Danville averages 1 inch 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 Danville?
- 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.
Danville winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 0.1 | 0.0 | 0.0 |
| February | 0.5 | 0.2 | 0.0 |
| March | 0.1 | 0.1 | 0.0 |
Danville next to nearby towns
Danville ranks 205 of 376 California cities here for ice-dam days, behind Truckee at 36.3 days.
- San Ramon, CA 4 mi, 0.0 days
- Walnut Creek, CA 7 mi, 0.0 days
- Dublin, CA 8 mi, 0.0 days
- Moraga, CA 9 mi, 0.0 days
- Clayton, CA 9 mi, 0.0 days
Where these numbers come from
NOAA 1991–2020 climate normals from Mt Diablo Junction, 5.1 miles from Danville. 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.
- The nearest weather station sits at a noticeably different elevation from Danville, so the snow figures may run high or low for the town itself.