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Will it freeze in Oak Forest in the next 7 nights?
No overnight lows at or below 32°F are forecast in Oak Forest during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 40°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM CST to Fri, Nov 6, 6:00 AM CST.
3 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 40°F Above 36°F · Patchy Drizzle then Mostly Cloudy
- Fri, Nov 6 35°F Frost possible · Partly Cloudy
- Sat, Nov 7 34°F Frost possible · Mostly Clear
- Sun, Nov 8 36°F Frost possible · Mostly Clear
- Mon, Nov 9 42°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 Oak Forest
The median first fall hard-freeze date (28°F) is October 30, from NOAA’s 1991–2020 Climate Normals at Park Forest. 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 20 · May 5 · May 24 | Sep 27 · Oct 10 · Oct 22 | 157 days |
| 32°F freeze | Apr 9 · Apr 23 · May 11 | Oct 6 · Oct 20 · Nov 1 | 179 days |
| 28°F hard freeze | Mar 30 · Apr 12 · Apr 27 | Oct 18 · Oct 30 · Nov 15 | 202 days |
Average high temperature by month
1991–2020 normals at Park Forest
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 Oak Forest, IL come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Park Forest (station USC00116616, elevation 710 ft), 8.6 mi from Oak Forest. 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 Oak Forest
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Midlothian, IL | 1.9 mi | Apr 10 | Nov 1 |
| Crestwood, IL | 2.5 mi | Apr 10 | Nov 1 |
| Markham, IL | 3.1 mi | Apr 23 | Oct 20 |
| Country Club Hills, IL | 3.1 mi | Apr 23 | Oct 20 |
| Tinley Park, IL | 3.7 mi | Apr 23 | Oct 20 |
| Posen, IL | 3.7 mi | Apr 10 | Nov 1 |
| Hazel Crest, IL | 4.3 mi | Apr 23 | Oct 20 |
| Alsip, IL | 4.3 mi | Apr 10 | Nov 1 |
| Palos Heights, IL | 4.3 mi | Apr 10 | Nov 1 |
| Orland Hills, IL | 5.0 mi | Apr 19 | Oct 22 |
Frequently asked questions
When is the last frost in Oak Forest?
On average, the last spring frost (32°F) in Oak Forest is around April 23. In about 1 year in 10 it comes after May 11, and in 9 years in 10 it comes after April 9.
When is the first frost in Oak Forest?
The first fall frost (32°F) usually arrives around October 20. There’s a 10% chance of a freeze by October 6 and a 90% chance by November 1.
Can it frost in Oak Forest 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 Oak Forest?
Oak Forest 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 60452. See growing zones in Illinois.
More: all Illinois frost dates · Illinois growing zones · UV index today in Oak Forest · frost vs. freeze