Ice dam risk in Glassboro, NJ
How often ice dams form in Glassboro
3.2 dam days a winter
Low risk. On an ordinary house in Glassboro, conditions for an ice dam come on about 3.2 days in a normal winter, mostly in February and January.
Glassboro averages 13 inches of snow a year and about 16 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 Glassboro
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 2.6 | Low |
| Typical, some insulation, not air-sealed | 3.2 | Low |
| Older or poorly insulated, warm attic | 3.9 | Low |
The attic matters less in Glassboro than in colder towns: there are only 0.6 days a winter between a typical attic and a sealed one.
What to do about ice dams in Glassboro
- 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.
Glassboro winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 5.0 | 5.1 | 1.2 |
| February | 5.0 | 5.9 | 1.3 |
| March | 1.4 | 1.9 | 0.3 |
| April | 0.2 | 0.1 | 0.0 |
| November | 0.1 | 0.0 | 0.0 |
| December | 1.6 | 2.5 | 0.5 |
Glassboro next to nearby towns
Glassboro ranks 101 of 116 New Jersey cities here for ice-dam days, behind Hopatcong at 14.7 days.
- Pine Hill, NJ 9 mi, 3.6 days
- Woodbury, NJ 10 mi, 3.0 days
- Lindenwold, NJ 10 mi, 3.6 days
- Bellmawr, NJ 12 mi, 3.0 days
- Gloucester City, NJ 13 mi, 2.3 days
Where these numbers come from
NOAA 1991–2020 climate normals from Woodstown Pittsgrov 4E, 11.0 miles from Glassboro. 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.