Ice dam risk in Lee's Summit, MO
Ice dams in Lee's Summit, MO: how often
5.2 dam days a winter
Moderate risk. On an ordinary house in Lee's Summit, conditions for an ice dam come on about 5.2 days in a normal winter, mostly in January and December.
Lee's Summit averages 13 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 Lee's Summit
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 3.2 | Low |
| Typical, some insulation, not air-sealed | 5.2 | Moderate |
| Older or poorly insulated, warm attic | 7.6 | Moderate |
The attic matters less in Lee's Summit than in colder towns: there are only 2.0 days a winter between a typical attic and a sealed one.
Preventing ice dams on a Lee's Summit 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.
Lee's Summit winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 3.6 | 7.6 | 2.4 |
| February | 2.6 | 4.0 | 1.0 |
| March | 1.7 | 2.0 | 0.3 |
| April | 0.2 | 0.2 | 0.0 |
| October | 0.4 | 0.2 | 0.0 |
| November | 1.2 | 0.8 | 0.1 |
| December | 3.5 | 5.2 | 1.4 |
Lee's Summit next to nearby towns
Lee's Summit ranks 8 of 80 Missouri cities here for ice-dam days, behind Maryville at 9.3 days.
- Raytown, MO 6 mi, 5.2 days
- Grandview, MO 8 mi, 4.6 days
- Blue Springs, MO 9 mi, 5.2 days
- Raymore, MO 9 mi, 4.8 days
- Belton, MO 11 mi, 4.4 days
Where these numbers come from
NOAA 1991–2020 climate normals from Independence, 9.9 miles from Lee's Summit. 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.