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Will it freeze in South Milwaukee in the next 7 nights?
No overnight lows at or below 32°F are forecast in South Milwaukee during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 38°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM CST to Fri, Nov 6, 6:00 AM CST.
2 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 38°F Above 36°F · Isolated Rain Showers then Mostly Cloudy
- Fri, Nov 6 33°F Frost possible · Partly Cloudy
- Sat, Nov 7 36°F Frost possible · Partly Cloudy
- Sun, Nov 8 38°F Above 36°F · Mostly Clear
- Mon, Nov 9 43°F Above 36°F · Mostly Clear
- Tue, Nov 10 40°F Above 36°F · Partly Cloudy
- Wed, Nov 11 41°F Above 36°F · 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 South Milwaukee
The median first fall hard-freeze date (28°F) is November 5, from NOAA’s 1991–2020 Climate Normals at South Milwaukee Wastewater Plant. 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 | Apr 21 · May 5 · May 24 | Oct 1 · Oct 16 · Oct 28 | 162 days |
| 32°F freeze | Apr 9 · Apr 22 · May 8 | Oct 10 · Oct 26 · Nov 8 | 184 days |
| 28°F hard freeze | Mar 28 · Apr 9 · Apr 24 | Oct 24 · Nov 5 · Nov 20 | 208 days |
Average high temperature by month
1991–2020 normals at South Milwaukee Wastewater Plant
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 South Milwaukee, WI come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: South Milwaukee Wastewater Plant (station USC00477964, elevation 650 ft), 1.1 mi from South Milwaukee. 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 South Milwaukee
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Cudahy, WI | 2.5 mi | Apr 19 | Oct 29 |
| Oak Creek, WI | 3.1 mi | Apr 22 | Oct 26 |
| St. Francis, WI | 4.3 mi | Apr 19 | Oct 29 |
| Greendale, WI | 7.5 mi | May 3 | Oct 14 |
| Franklin, WI | 8.1 mi | May 3 | Oct 14 |
| Greenfield, WI | 8.1 mi | May 3 | Oct 14 |
| Caledonia, WI | 8.1 mi | Apr 24 | Oct 24 |
| Hales Corners, WI | 9.9 mi | May 3 | Oct 14 |
| West Allis, WI | 11 mi | Apr 26 | Oct 22 |
| Milwaukee, WI | 12 mi | Apr 26 | Oct 18 |
Frequently asked questions
When is the last frost in South Milwaukee?
On average, the last spring frost (32°F) in South Milwaukee is around April 22. In about 1 year in 10 it comes after May 8, and in 9 years in 10 it comes after April 9.
When is the first frost in South Milwaukee?
The first fall frost (32°F) usually arrives around October 26. There’s a 10% chance of a freeze by October 10 and a 90% chance by November 8.
Can it frost in South Milwaukee 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 5.
What growing zone is South Milwaukee?
South Milwaukee is in USDA Plant Hardiness Zone 6a (average annual extreme minimum temperature −10 to −5°F), based on the 2023 USDA map for ZIP code 53172. See growing zones in Wisconsin.
More: all Wisconsin frost dates · Wisconsin growing zones · frost vs. freeze