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Will it freeze in Macomb in the next 7 nights?
The earliest overnight low at or below 32°F in the available NWS frost forecast is Fri, Nov 6: 28°F (Fri, Nov 6, 6:00 PM CST to Sat, Nov 7, 6:00 AM CST).
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 Cloudy
- Fri, Nov 6 28°F Hard freeze · Mostly Clear
- Sat, Nov 7 32°F Freeze · Mostly Clear
- Sun, Nov 8 35°F Frost possible · Clear
- Mon, Nov 9 41°F Above 36°F · Clear
- Tue, Nov 10 40°F Above 36°F · Mostly Clear
- Wed, Nov 11 41°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 Macomb
The median first fall hard-freeze date (28°F) is October 30, from NOAA’s 1991–2020 Climate Normals at Prairie City 2S. 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 15 · Apr 28 · May 12 | Sep 29 · Oct 12 · Oct 24 | 165 days |
| 32°F freeze | Apr 4 · Apr 17 · May 2 | Oct 7 · Oct 22 · Nov 1 | 185 days |
| 28°F hard freeze | Mar 22 · Apr 7 · Apr 21 | Oct 18 · Oct 30 · Nov 13 | 204 days |
Average high temperature by month
1991–2020 normals at Prairie City 2S
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 Macomb, IL come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Prairie City 2S (station USC00116970, elevation 650 ft), 14 mi from Macomb. 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 Macomb
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Monmouth, IL | 30 mi | Apr 22 | Oct 15 |
| Burlington, IA | 33 mi | Apr 15 | Oct 20 |
| Beardstown, IL | 34 mi | Apr 16 | Oct 23 |
| Canton, IL | 35 mi | Apr 17 | Oct 19 |
| Fort Madison, IA | 37 mi | Apr 12 | Oct 25 |
| Galesburg, IL | 37 mi | Apr 20 | Oct 19 |
| Keokuk, IA | 38 mi | Apr 10 | Oct 27 |
| Quincy, IL | 52 mi | Apr 8 | Oct 30 |
| Bartonville, IL | 55 mi | Apr 16 | Oct 23 |
| Pekin, IL | 56 mi | Apr 16 | Oct 23 |
Frequently asked questions
When is the last frost in Macomb?
On average, the last spring frost (32°F) in Macomb is around April 17. In about 1 year in 10 it comes after May 2, and in 9 years in 10 it comes after April 4.
When is the first frost in Macomb?
The first fall frost (32°F) usually arrives around October 22. There’s a 10% chance of a freeze by October 7 and a 90% chance by November 1.
Can it frost in Macomb 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 28.
What growing zone is Macomb?
Macomb 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 61455. See growing zones in Illinois.
More: all Illinois frost dates · Illinois growing zones · frost vs. freeze