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Will it freeze in Lemont in the next 7 nights?
No overnight lows at or below 32°F are forecast in Lemont during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 39°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 39°F Above 36°F · Chance Rain Showers then Mostly Cloudy
- Fri, Nov 6 33°F Frost possible · Mostly Clear
- 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 39°F Above 36°F · Partly Cloudy
- Wed, Nov 11 40°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 Lemont
The median first fall hard-freeze date (28°F) is November 1, from NOAA’s 1991–2020 Climate Normals at Little Red School Hse. 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 16 · Apr 30 · May 18 | Sep 28 · Oct 12 · Oct 24 | 163 days |
| 32°F freeze | Apr 6 · Apr 19 · May 5 | Oct 8 · Oct 22 · Nov 3 | 183 days |
| 28°F hard freeze | Mar 26 · Apr 7 · Apr 22 | Oct 19 · Nov 1 · Nov 16 | 206 days |
Average high temperature by month
1991–2020 normals at Little Red School Hse
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 Lemont, IL come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Little Red School Hse (station USC00115110, elevation 715 ft), 6.3 mi from Lemont. 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 Lemont
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Homer Glen, IL | 4.3 mi | Apr 20 | Oct 22 |
| Darien, IL | 5.6 mi | Apr 19 | Oct 22 |
| Woodridge, IL | 5.6 mi | Apr 28 | Oct 16 |
| Lockport, IL | 5.6 mi | Apr 20 | Oct 22 |
| Bolingbrook, IL | 6.2 mi | Apr 20 | Oct 22 |
| Burr Ridge, IL | 6.2 mi | Apr 19 | Oct 22 |
| Romeoville, IL | 6.8 mi | Apr 20 | Oct 22 |
| Willow Springs, IL | 6.8 mi | Apr 19 | Oct 22 |
| Willowbrook, IL | 7.5 mi | Apr 19 | Oct 22 |
| Orland Park, IL | 7.5 mi | Apr 19 | Oct 22 |
Frequently asked questions
When is the last frost in Lemont?
On average, the last spring frost (32°F) in Lemont is around April 19. In about 1 year in 10 it comes after May 5, and in 9 years in 10 it comes after April 6.
When is the first frost in Lemont?
The first fall frost (32°F) usually arrives around October 22. There’s a 10% chance of a freeze by October 8 and a 90% chance by November 3.
Can it frost in Lemont 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 30.
What growing zone is Lemont?
Lemont 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 60439. See growing zones in Illinois.
More: all Illinois frost dates · Illinois growing zones · frost vs. freeze