How cold is too cold for chickens?
Colder than most people think. Healthy hens that have had the fall to get used to the cold handle an ordinary winter night. University extension guides from Kentucky and Purdue draw the line at single digits: below about 10°F, combs and wattles can freeze, worst in a damp or drafty coop.
The nights worth a look
These are the nights our coop call emails about, by early afternoon (between 1 pm and 3 pm), October through March. One call a night at most; a cold spell gets one call, and another only if it deepens.
| Night | Tonight’s forecast | Why |
|---|---|---|
| Single digits | A low of 9°F or colder | The line Kentucky and Purdue extension draw. |
| Cold and windy | 15°F or colder with a wind chill of 0°F or below | Wind makes cold harder on birds in a drafty coop (Ohio State); this number is ours. |
| Bitter | Below 0°F, or a wind chill of −15°F or below | A second call when a cold spell deepens. |
| First hard freeze of the fall | 28°F or colder, the first night since August | Time for a heated waterer (Purdue). |
| Sharp drop | 20°F or more below the last three nights, to 20°F or colder | Hens need time to get used to cold (Ohio State). |
What to do on those nights
The care steps the extension guides agree on, as our coop call gives them:
- Combs and wattles can freeze in the single digits, worst in a damp or drafty coop (Kentucky and Purdue extension). Leave the high vents open but keep drafts off the roost, keep the bedding dry, and check that the water hasn’t frozen. Heat lamps are a common cause of coop fires; most healthy hens don’t need one.
- Water left out will freeze tonight. Extension guides (Purdue, UNH, Delaware State) say to switch to a heated base or bowl, or bring fresh water morning and evening, more often while it stays below freezing; hens shouldn’t go more than about 10 hours without water.
- Hens handle cold well once they have had time to get used to it (Ohio State, UMaine); a sudden drop gives them none. Keep drafts off the roost and the bedding dry, and check the water before dark.
How often it came last winter
We replayed winter 2025–26 (October to March) at seven airports across the region, with the weather that actually came standing in for the forecast. The coop call came 5 to 11 times a place, 54 in all, most of them in December and January. Airports run warmer than rural coops, so a real coop may see a few more.
| Place | First hard freeze | Cold nights | Sharp drops | All calls |
|---|---|---|---|---|
| Bangor, ME | Nov 2 (24°F) | 9 | 1 | 11 |
| Worcester, MA | Nov 14 (28°F) | 8 | 0 | 9 |
| Albany, NY | Nov 1 (28°F) | 7 | 0 | 8 |
| Burlington, VT | Nov 6 (28°F) | 6 | 0 | 7 |
| Concord, NH | Oct 9 (26°F) | 6 | 0 | 7 |
| Hartford, CT | Nov 6 (27°F) | 6 | 0 | 7 |
| Williamsport, PA | Oct 27 (28°F) | 4 | 0 | 5 |
All seven places by month: October 2, November 5, December 20, January 16, February 9, March 2.
And on hot days
Heat is the other end. We use the Livestock Weather Safety Index: 79 to 83 is danger and 84 or more is emergency. From May to September we email before the first hot, humid day of a run, with shade, cool water and a breeze through the coop.
Sources
- Purdue University, “Poultry experts: Keep birds warm, dry in winter” (2015)
- University of Kentucky, J. Jacob, on cold nights and combs (Poultry Extension)
- Ohio State University Extension, “Winter and Your Backyard Chickens” (ANR-66)
Get the coop call by email
Farm & Barn emails your coop’s coldest nights and the fall’s first hard freeze by early afternoon, plus hot days for animals and county fairs. $49 a year, for one place.
See the coop call and sample alertsUpdated November 2026.