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Will it freeze in Wauwatosa 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 36°F. Frost possible.
NWS forecast period: Thu, Nov 5, 6:00 PM CST to Fri, Nov 6, 6:00 AM CST.
4 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 36°F Frost possible · Mostly Cloudy
- Fri, Nov 6 30°F Freeze · Mostly Clear
- Sat, Nov 7 34°F Frost possible · Partly Cloudy
- Sun, Nov 8 35°F Frost possible · Mostly Clear
- Mon, Nov 9 41°F Above 36°F · Mostly Clear
- Tue, Nov 10 37°F Above 36°F · Partly Cloudy
- Wed, Nov 11 39°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 Wauwatosa
The median first fall hard-freeze date (28°F) is October 30, from NOAA’s 1991–2020 Climate Normals at Mt Mary College. 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 24 · May 8 · May 24 | Sep 25 · Oct 6 · Oct 22 | 150 days |
| 32°F freeze | Apr 12 · Apr 26 · May 12 | Oct 2 · Oct 18 · Nov 1 | 173 days |
| 28°F hard freeze | Apr 1 · Apr 14 · Apr 30 | Oct 13 · Oct 30 · Nov 11 | 196 days |
Average high temperature by month
1991–2020 normals at Mt Mary College
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 Wauwatosa, WI come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Mt Mary College (station USC00475474, elevation 715 ft), 0.7 mi from Wauwatosa. 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 Wauwatosa
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Elm Grove, WI | 3.1 mi | Apr 26 | Oct 18 |
| Milwaukee, WI | 3.7 mi | Apr 26 | Oct 18 |
| West Allis, WI | 3.7 mi | Apr 26 | Oct 22 |
| Brookfield, WI | 4.3 mi | Apr 30 | Oct 14 |
| Glendale, WI | 6.8 mi | Apr 26 | Oct 18 |
| Greenfield, WI | 7.5 mi | May 3 | Oct 14 |
| Whitefish Bay, WI | 7.5 mi | Apr 26 | Oct 18 |
| Shorewood, WI | 7.5 mi | Apr 26 | Oct 18 |
| New Berlin, WI | 8.1 mi | May 3 | Oct 14 |
| Menomonee Falls, WI | 8.1 mi | May 6 | Oct 8 |
Frequently asked questions
When is the last frost in Wauwatosa?
On average, the last spring frost (32°F) in Wauwatosa is around April 26. In about 1 year in 10 it comes after May 12, and in 9 years in 10 it comes after April 12.
When is the first frost in Wauwatosa?
The first fall frost (32°F) usually arrives around October 18. There’s a 10% chance of a freeze by October 2 and a 90% chance by November 1.
Can it frost in Wauwatosa 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 8.
What growing zone is Wauwatosa?
Wauwatosa 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 53226. See growing zones in Wisconsin.
More: all Wisconsin frost dates · Wisconsin growing zones · UV index today in Wauwatosa · frost vs. freeze