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Will it freeze in Chicago in the next 7 nights?
No overnight lows at or below 32°F are forecast in Chicago 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.
No nights at or below 36°F in the National Weather Service forecast for the next 7 nights.
- Tonight 40°F Above 36°F · Chance Rain Showers then Mostly Cloudy
- Fri, Nov 6 37°F Above 36°F · Partly Cloudy
- Sat, Nov 7 38°F Above 36°F · Mostly Clear
- Sun, Nov 8 39°F Above 36°F · Mostly Clear
- Mon, Nov 9 44°F Above 36°F · Mostly Clear
- Tue, Nov 10 42°F Above 36°F · Partly Cloudy
- Wed, Nov 11 43°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 Chicago
The median first fall hard-freeze date (28°F) is November 15, from NOAA’s 1991–2020 Climate Normals at Chicago Northerly Island. 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 9 · Apr 23 · May 9 | Oct 12 · Oct 26 · Nov 7 | 185 days |
| 32°F freeze | Mar 29 · Apr 10 · Apr 25 | Oct 24 · Nov 5 · Nov 20 | 208 days |
| 28°F hard freeze | Mar 16 · Apr 1 · Apr 14 | Nov 2 · Nov 15 · Dec 1 | 229 days |
Average high temperature by month
1991–2020 normals at Chicago Northerly Island
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 Chicago, IL come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Chicago Northerly Island (station USC00111550, elevation 583 ft), 4.1 mi from Chicago. 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 Chicago
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Cicero, IL | 3.7 mi | Apr 11 | Oct 31 |
| Stickney, IL | 5.0 mi | Apr 11 | Oct 31 |
| Berwyn, IL | 5.6 mi | Apr 11 | Oct 31 |
| Oak Park, IL | 6.2 mi | Apr 11 | Oct 31 |
| Riverside, IL | 6.8 mi | Apr 11 | Oct 31 |
| Forest Park, IL | 6.8 mi | Apr 11 | Oct 31 |
| Lyons, IL | 6.8 mi | Apr 11 | Oct 31 |
| North Riverside, IL | 7.5 mi | Apr 11 | Oct 31 |
| Summit, IL | 7.5 mi | Apr 11 | Oct 31 |
| Burbank, IL | 7.5 mi | Apr 10 | Nov 1 |
Frequently asked questions
When is the last frost in Chicago?
On average, the last spring frost (32°F) in Chicago is around April 10. In about 1 year in 10 it comes after April 25, and in 9 years in 10 it comes after March 29.
When is the first frost in Chicago?
The first fall frost (32°F) usually arrives around November 5. There’s a 10% chance of a freeze by October 24 and a 90% chance by November 20.
Can it frost in Chicago 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 April 23.
What growing zone is Chicago?
Chicago 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 60608. See growing zones in Illinois.
More: all Illinois frost dates · Illinois growing zones · UV index today in Chicago · frost vs. freeze