Ice dam risk in Kansas City, MO
Will your roof get ice dams in Kansas City, MO?
4.5 dam days a winter
Low risk. On an ordinary house in Kansas City, conditions for an ice dam come on about 4.5 days in a normal winter, mostly in January and December.
Kansas City averages 11 inches of snow a year and about 20 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 Kansas City
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 2.9 | Low |
| Typical, some insulation, not air-sealed | 4.5 | Low |
| Older or poorly insulated, warm attic | 6.5 | Moderate |
The attic matters less in Kansas City than in colder towns: there are only 1.6 days a winter between a typical attic and a sealed one.
What to do about ice dams in Kansas City
- 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.
Kansas City winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 3.4 | 7.6 | 2.2 |
| February | 3.2 | 4.0 | 0.9 |
| March | 0.4 | 2.0 | 0.2 |
| April | 0.1 | 0.2 | 0.0 |
| October | 0.3 | 0.2 | 0.0 |
| November | 0.1 | 0.8 | 0.1 |
| December | 3.5 | 5.2 | 1.2 |
Kansas City next to nearby towns
Kansas City ranks 21 of 80 Missouri cities here for ice-dam days, behind Maryville at 9.3 days.
- Gladstone, MO 6 mi, 4.7 days
- Mission, KS 9 mi, 4.4 days
- Raytown, MO 10 mi, 5.2 days
- Kansas City, KS 10 mi, 4.4 days
- Prairie Village, KS 11 mi, 4.6 days
Where these numbers come from
NOAA 1991–2020 climate normals from Kansas City Dwtn Airport, 2.1 miles from Kansas City. 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.
- Snow-on-the-ground counts come from a second, nearby station, because the closest one does not record them.