Ice dam risk in Patchogue, NY
Ice dams in Patchogue, NY: how often
5.0 dam days a winter
Moderate risk. On an ordinary house in Patchogue, conditions for an ice dam come on about 5.0 days in a normal winter, mostly in February and January.
Patchogue averages 32 inches of snow a year and about 23 days with snow on the ground. Plenty falls, but it tends to melt off between storms, which keeps the count lower than the snowfall suggests. That gap is why snowfall alone misleads.
What your attic does to that number in Patchogue
| Attic | Dam days | Risk |
|---|---|---|
| Air-sealed and well insulated | 3.6 | Low |
| Typical, some insulation, not air-sealed | 5.0 | Moderate |
| Older or poorly insulated, warm attic | 6.8 | Moderate |
The attic matters less in Patchogue than in colder towns: there are only 1.4 days a winter between a typical attic and a sealed one.
What to do about ice dams in Patchogue
- Rake the bottom three or four feet of roof after any storm that leaves more than about six inches, from the ground with a roof rake.
More on when a roof rake is worth it.
Patchogue winter, month by month
| Month | Snow (in) | Days on ground | Dam days |
|---|---|---|---|
| January | 10.3 | 7.2 | 1.9 |
| February | 9.4 | 8.6 | 2.1 |
| March | 6.5 | 3.8 | 0.6 |
| April | 0.6 | 0.2 | 0.0 |
| November | 0.5 | 0.1 | 0.0 |
| December | 4.5 | 2.8 | 0.5 |
Patchogue next to nearby towns
Patchogue ranks 72 of 90 New York cities here for ice-dam days, behind Utica at 46.1 days.
- Lake Grove, NY 8 mi, 5.0 days
- Babylon, NY 17 mi, 5.0 days
- Lindenhurst, NY 19 mi, 4.4 days
- Massapequa Park, NY 23 mi, 3.9 days
- Westbury, NY 30 mi, 3.9 days
Where these numbers come from
NOAA 1991–2020 climate normals from Islip-Li Macarthur Airport, 4.8 miles from Patchogue. 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.