Ice dam risk in Leavenworth, KS
Ice dams in Leavenworth, KS: how often
4.7 dam days a winter
Low risk. On an ordinary house in Leavenworth, conditions for an ice dam come on about 4.7 days in a normal winter, mostly in January and February.
Leavenworth averages 19 inches of snow a year and about 19 days with snow on the ground. Most of it comes and goes within a few days. The conditions that make a dam need all three at once: snow, cold at the eave and heat above it.
What your attic does to that number in Leavenworth
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 3.0 | Low |
| Typical, some insulation, not air-sealed | 4.7 | Low |
| Older or poorly insulated, warm attic | 6.8 | Moderate |
The attic matters less in Leavenworth than in colder towns: there are only 1.7 days a winter between a typical attic and a sealed one.
Preventing ice dams on a Leavenworth roof
- Check the gutters before the first snow and clear them, so meltwater has somewhere to go. If you see icicles thicker than a finger along the eave after a storm, that is the early sign to look at the attic.
Snowy places are not always the worst: why snowfall misleads.
Leavenworth winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 4.8 | 7.4 | 2.2 |
| February | 5.6 | 5.3 | 1.2 |
| March | 1.5 | 1.1 | 0.1 |
| October | 0.4 | 0.1 | 0.0 |
| November | 1.0 | 0.2 | 0.0 |
| December | 5.5 | 4.7 | 1.2 |
Leavenworth next to nearby towns
Leavenworth ranks 6 of 38 Kansas cities here for ice-dam days, behind Salina at 5.8 days.
- Lansing, KS 6 mi, 4.7 days
- Kansas City, KS 17 mi, 4.4 days
- Smithville, MO 20 mi, 5.2 days
- Atchison, KS 20 mi, 5.7 days
- Gladstone, MO 21 mi, 4.7 days
Where these numbers come from
NOAA 1991–2020 climate normals from Leavenworth, 0.4 miles from Leavenworth. 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.