Ice dam risk in Chillicothe, OH

Ice dams in Chillicothe, OH: how often

5.2 dam days a winter

Moderate risk. On an ordinary house in Chillicothe, conditions for an ice dam come on about 5.2 days in a normal winter, mostly in January and February.

Chillicothe averages 12 inches of snow a year and about 21 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 Chillicothe

Attic	Dam days	Risk
Air-sealed and well insulated	3.5	Low
Typical, some insulation, not air-sealed	5.2	Moderate
Older or poorly insulated, warm attic	7.4	Moderate

The attic matters less in Chillicothe than in colder towns: there are only 1.7 days a winter between a typical attic and a sealed one.

What to do about ice dams in Chillicothe

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.

Chillicothe winter, month by month

Month	Snow (in)	Days on ground	Dam days
January	5.0	9.0	2.5
February	3.5	5.9	1.5
March	0.9	1.7	0.3
November	0.1	0.6	0.1
December	2.0	3.5	0.8

Chillicothe next to nearby towns

Chillicothe ranks 170 of 176 Ohio cities here for ice-dam days, behind Euclid at 24.8 days.

Circleville, OH 18 mi, 5.2 days
Washington Court House, OH 27 mi, 5.6 days
Lancaster, OH 34 mi, 5.2 days
Canal Winchester, OH 36 mi, 6.7 days
Grove City, OH 37 mi, 6.7 days

Where these numbers come from

NOAA 1991–2020 climate normals from Waverly, 15.9 miles from Chillicothe. 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.