Ice dam risk in Lenexa, KS
How often ice dams form in Lenexa
4.4 dam days a winter
Low risk. On an ordinary house in Lenexa, conditions for an ice dam come on about 4.4 days in a normal winter, mostly in January and February.
Lenexa averages 14 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 Lenexa
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 2.9 | Low |
| Typical, some insulation, not air-sealed | 4.4 | Low |
| Older or poorly insulated, warm attic | 6.3 | Moderate |
The attic matters less in Lenexa than in colder towns: there are only 1.5 days a winter between a typical attic and a sealed one.
What to do about ice dams in Lenexa
- 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.
Lenexa winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 3.9 | 7.9 | 2.2 |
| February | 3.3 | 4.8 | 1.0 |
| March | 1.4 | 1.6 | 0.2 |
| April | 0.3 | 0.0 | 0.0 |
| October | 0.3 | 0.1 | 0.0 |
| November | 1.2 | 0.5 | 0.1 |
| December | 3.4 | 3.8 | 0.9 |
Lenexa next to nearby towns
Lenexa ranks 17 of 38 Kansas cities here for ice-dam days, behind Salina at 5.8 days.
- Shawnee, KS 4 mi, 5.1 days
- Olathe, KS 6 mi, 4.4 days
- Merriam, KS 7 mi, 4.4 days
- Overland Park, KS 8 mi, 4.4 days
- Mission, KS 9 mi, 4.4 days
Where these numbers come from
NOAA 1991–2020 climate normals from Olathe 3E, 5.9 miles from Lenexa. 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.