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Will it freeze in Green Bay in the next 7 nights?
The earliest overnight low at or below 32°F in the available NWS frost forecast is Fri, Nov 6: 30°F (Fri, Nov 6, 6:00 PM CST to Sat, Nov 7, 6:00 AM CST).
Tonight: forecast low 35°F. Frost possible.
NWS forecast period: Thu, Nov 5, 6:00 PM CST to Fri, Nov 6, 6:00 AM CST.
6 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 35°F Frost possible · Chance Rain Showers
- Fri, Nov 6 30°F Freeze · Mostly Clear
- Sat, Nov 7 34°F Frost possible · Partly Cloudy
- Sun, Nov 8 34°F Frost possible · Mostly Clear
- Mon, Nov 9 40°F Above 36°F · Mostly Clear
- Tue, Nov 10 36°F Frost possible · Partly Cloudy
- Wed, Nov 11 36°F Frost possible · Partly Cloudy
Overnight lows from the National Weather Service forecast for this location. This covers the available forecast window, not the first freeze of the whole season. Frost can form above 32°F on clear, calm nights.
Frost and freeze probabilities
Freeze dates shift from year to year. Spring percentages describe the chance of a freeze after the stated date; fall percentages describe the chance of a freeze by that date. The 10% spring date is the cautious one: a later freeze happens about 1 year in 10.
These dates describe historical probabilities, not this year’s forecast or the earliest and latest possible freezes. Different weather stations or probability thresholds can produce different published dates for the same city.
Average first hard freeze in Green Bay
The median first fall hard-freeze date (28°F) is October 25, from NOAA’s 1991–2020 Climate Normals at Green Bay Botanical. This is the 50% probability date, not a forecast for this year.
| Temperature | Last spring date 90% · 50% · 10% chance of a later freeze | First fall date 10% · 50% · 90% chance of an earlier freeze | Season |
|---|---|---|---|
| 36°F frost possible | May 4 · May 19 · May 31 | Sep 15 · Sep 28 · Oct 12 | 132 days |
| 32°F freeze | Apr 24 · May 7 · May 22 | Sep 23 · Oct 9 · Oct 25 | 154 days |
| 28°F hard freeze | Apr 10 · Apr 27 · May 12 | Oct 5 · Oct 25 · Nov 7 | 180 days |
Average high temperature by month
1991–2020 normals at Green Bay Botanical
Average low temperature by month
Months with lows near or below freezing carry frost risk
Where these frost dates come from
The frost dates for Green Bay, WI come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Green Bay Botanical (station USC00473271, elevation 694 ft), 5.5 mi from Green Bay. Local conditions (valleys, hilltops, distance to water, city heat) can shift frost dates by days or weeks. The hardiness zone is from the 2023 USDA Plant Hardiness Zone Map (USDA ARS and Oregon State University PRISM). See our methodology.
Frost dates near Green Bay
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Allouez, WI | 3.7 mi | Apr 30 | Oct 9 |
| Bellevue, WI | 4.3 mi | Apr 30 | Oct 9 |
| Howard, WI | 5.6 mi | May 7 | Oct 9 |
| Ashwaubenon, WI | 5.6 mi | Apr 30 | Oct 9 |
| Suamico, WI | 7.5 mi | May 7 | Oct 9 |
| De Pere, WI | 8.1 mi | Apr 30 | Oct 9 |
| Hobart, WI | 8.7 mi | May 1 | Oct 11 |
| Kaukauna, WI | 22 mi | May 4 | Oct 6 |
| Little Chute, WI | 23 mi | May 4 | Oct 6 |
| Kimberly, WI | 25 mi | May 4 | Oct 6 |
Frequently asked questions
When is the last frost in Green Bay?
On average, the last spring frost (32°F) in Green Bay is around May 7. In about 1 year in 10 it comes after May 22, and in 9 years in 10 it comes after April 24.
When is the first frost in Green Bay?
The first fall frost (32°F) usually arrives around October 9. There’s a 10% chance of a freeze by September 23 and a 90% chance by October 25.
Can it frost in Green Bay after the last frost date?
Yes. Frost can form on clear, calm nights even when the air stays above 32°F. Temperatures of 36°F or lower, cold enough for frost on exposed plants, have a 50% chance of occurring after May 19.
What growing zone is Green Bay?
Green Bay is in USDA Plant Hardiness Zone 5b (average annual extreme minimum temperature −15 to −10°F), based on the 2023 USDA map for ZIP code 54302. See growing zones in Wisconsin.
More: all Wisconsin frost dates · Wisconsin growing zones · UV index today in Green Bay · frost vs. freeze