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Will it freeze in Freeport in the next 7 nights?
The earliest overnight low at or below 32°F in the available NWS frost forecast is Fri, Nov 6: 26°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.
5 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 35°F Frost possible · Mostly Cloudy
- Fri, Nov 6 26°F Hard freeze · Mostly Clear
- Sat, Nov 7 32°F Freeze · Mostly Clear
- Sun, Nov 8 33°F Frost possible · Mostly Clear
- Mon, Nov 9 38°F Above 36°F · Mostly Clear
- Tue, Nov 10 36°F Frost possible · Partly Cloudy
- Wed, Nov 11 37°F Above 36°F · Mostly Clear
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 Freeport
The median first fall hard-freeze date (28°F) is October 24, from NOAA’s 1991–2020 Climate Normals at Freeport Waste Water Treatment 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 22 · May 6 · May 21 | Sep 22 · Oct 3 · Oct 15 | 150 days |
| 32°F freeze | Apr 11 · Apr 26 · May 11 | Sep 30 · Oct 13 · Oct 26 | 169 days |
| 28°F hard freeze | Mar 31 · Apr 14 · Apr 30 | Oct 10 · Oct 24 · Nov 5 | 192 days |
Average high temperature by month
1991–2020 normals at Freeport Waste Water Treatment 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 Freeport, IL come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Freeport Waste Water Treatment Plant (station USC00113262, elevation 750 ft), 1.7 mi from Freeport. 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 Freeport
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Monroe, WI | 22 mi | Apr 27 | Oct 14 |
| Rockford, IL | 29 mi | Apr 24 | Oct 17 |
| Rockton, IL | 31 mi | May 1 | Oct 12 |
| Machesney Park, IL | 32 mi | May 1 | Oct 12 |
| Dixon, IL | 32 mi | Apr 21 | Oct 19 |
| Loves Park, IL | 33 mi | Apr 24 | Oct 17 |
| Roscoe, IL | 34 mi | May 1 | Oct 12 |
| South Beloit, IL | 34 mi | May 1 | Oct 12 |
| Sterling, IL | 34 mi | Apr 21 | Oct 19 |
| Beloit, WI | 35 mi | May 1 | Oct 12 |
Frequently asked questions
When is the last frost in Freeport?
On average, the last spring frost (32°F) in Freeport is around April 26. In about 1 year in 10 it comes after May 11, and in 9 years in 10 it comes after April 11.
When is the first frost in Freeport?
The first fall frost (32°F) usually arrives around October 13. There’s a 10% chance of a freeze by September 30 and a 90% chance by October 26.
Can it frost in Freeport 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 6.
What growing zone is Freeport?
Freeport is in USDA Plant Hardiness Zone 5a (average annual extreme minimum temperature −20 to −15°F), based on the 2023 USDA map for ZIP code 61032. See growing zones in Illinois.
More: all Illinois frost dates · Illinois growing zones · frost vs. freeze