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Will it freeze in Spencer in the next 7 nights?
The earliest overnight low at or below 32°F in the available NWS frost forecast is Tonight: 32°F (Thu, Nov 5, 6:00 PM CST to Fri, Nov 6, 6:00 AM CST).
Tonight: forecast low 32°F. Freeze.
NWS forecast period: Thu, Nov 5, 6:00 PM CST to Fri, Nov 6, 6:00 AM CST.
4 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 32°F Freeze · Cloudy
- Fri, Nov 6 28°F Hard freeze · Partly Cloudy
- Sat, Nov 7 33°F Frost possible · Partly Cloudy
- Sun, Nov 8 37°F Above 36°F · Mostly Clear
- Mon, Nov 9 36°F Frost possible · Mostly Clear
- Tue, Nov 10 37°F Above 36°F · Partly Cloudy
- Wed, Nov 11 38°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 Spencer
The median first fall hard-freeze date (28°F) is October 14, from NOAA’s 1991–2020 Climate Normals at Spencer 1 N. 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 29 · May 10 · May 23 | Sep 11 · Sep 24 · Oct 7 | 137 days |
| 32°F freeze | Apr 18 · May 1 · May 14 | Sep 20 · Oct 3 · Oct 17 | 154 days |
| 28°F hard freeze | Apr 8 · Apr 22 · May 5 | Sep 28 · Oct 14 · Oct 27 | 174 days |
Average high temperature by month
1991–2020 normals at Spencer 1 N
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 Spencer, IA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Spencer 1 N (station USC00137844, elevation 1,326 ft), 1.3 mi from Spencer. 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 Spencer
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Spirit Lake, IA | 19 mi | Apr 28 | Oct 11 |
| Estherville, IA | 24 mi | May 2 | Oct 3 |
| Cherokee, IA | 34 mi | May 4 | Oct 4 |
| Sheldon, IA | 35 mi | May 5 | Sep 28 |
| Storm Lake, IA | 35 mi | Apr 25 | Oct 13 |
| Worthington, MN | 40 mi | May 3 | Oct 4 |
| Orange City, IA | 47 mi | Apr 30 | Oct 3 |
| Algona, IA | 47 mi | Apr 30 | Oct 6 |
| Fairmont, MN | 48 mi | Apr 25 | Oct 14 |
| Sioux Center, IA | 52 mi | Apr 30 | Oct 3 |
Frequently asked questions
When is the last frost in Spencer?
On average, the last spring frost (32°F) in Spencer is around May 1. In about 1 year in 10 it comes after May 14, and in 9 years in 10 it comes after April 18.
When is the first frost in Spencer?
The first fall frost (32°F) usually arrives around October 3. There’s a 10% chance of a freeze by September 20 and a 90% chance by October 17.
Can it frost in Spencer 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 10.
What growing zone is Spencer?
Spencer is in USDA Plant Hardiness Zone 5a (average annual extreme minimum temperature −20 to −15°F), based on the 2023 USDA map for ZIP code 51301. See growing zones in Iowa.
More: all Iowa frost dates · Iowa growing zones · frost vs. freeze