Frost dates 2026–2027

Frost dates for Montgomery, Illinois

Median (50% chance) dates of the last and first 32°F frost, from NOAA 1991–2020 climate normals at Aurora, 4.8 mi away (close match).

Last spring frostApr 19
First fall frostOct 23
185 frost-free days
Last spring frostApr 191 year in 10 after May 4
First fall frostOct 231 year in 10 by Oct 9
Growing season185 daysbetween median 32°F dates
Hardiness zoneZone 5b−15 to −10°F average extreme low

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Will it freeze in Montgomery in the next 7 nights?

The earliest overnight low at or below 32°F in the available NWS frost forecast is Fri, Nov 6: 30°F (Fri, Nov 6, 6:00 PM CST to Sat, Nov 7, 6:00 AM CST).

Tonight: forecast low 38°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.

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 Montgomery

The median first fall hard-freeze date (28°F) is November 2, from NOAA’s 1991–2020 Climate Normals at Aurora. This is the 50% probability date, not a forecast for this year.

TemperatureLast 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 17 · May 1 · May 19 Sep 29 · Oct 13 · Oct 25 164 days
32°F freeze Apr 5 · Apr 19 · May 4 Oct 9 · Oct 23 · Nov 3 185 days
28°F hard freeze Mar 25 · Apr 8 · Apr 23 Oct 21 · Nov 2 · Nov 16 207 days
NOAA NCEI U.S. Climate Normals 1991–2020, station USC00110338. How to read these probabilities.

Average high temperature by month

1991–2020 normals at Aurora

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 Montgomery, IL come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Aurora (station USC00110338, elevation 660 ft), 4.8 mi from Montgomery. 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 Montgomery

CityDistanceLast spring frostFirst fall frost
Oswego, IL 2.5 mi Apr 19 Oct 23
Aurora, IL 4.3 mi Apr 19 Oct 23
Yorkville, IL 5.6 mi Apr 28 Oct 13
Sugar Grove, IL 6.2 mi Apr 28 Oct 13
North Aurora, IL 6.2 mi Apr 19 Oct 23
Batavia, IL 9.3 mi Apr 19 Oct 23
Plano, IL 9.3 mi Apr 28 Oct 13
Plainfield, IL 9.9 mi Apr 20 Oct 22
Naperville, IL 11 mi Apr 28 Oct 16
Warrenville, IL 11 mi Apr 28 Oct 16

Frequently asked questions

When is the last frost in Montgomery?

On average, the last spring frost (32°F) in Montgomery is around April 19. In about 1 year in 10 it comes after May 4, and in 9 years in 10 it comes after April 5.

When is the first frost in Montgomery?

The first fall frost (32°F) usually arrives around October 23. There’s a 10% chance of a freeze by October 9 and a 90% chance by November 3.

Can it frost in Montgomery 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 1.

What growing zone is Montgomery?

Montgomery is in USDA Plant Hardiness Zone 5b (average annual extreme minimum temperature −15 to −10°F), based on the 2023 USDA map for ZIP code 60538. See growing zones in Illinois.

More: all Illinois frost dates · Illinois growing zones · frost vs. freeze