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Will it freeze in Caribou in the next 7 nights?
The earliest overnight low at or below 32°F in the available NWS frost forecast is Sun, Nov 8: 32°F (Sun, Nov 8, 6:00 PM EST to Mon, Nov 9, 6:00 AM EST).
Tonight: forecast low 53°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM EST to Fri, Nov 6, 6:00 AM EST.
4 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 53°F Above 36°F · Chance Light Rain
- Fri, Nov 6 39°F Above 36°F · Chance Light Rain
- Sat, Nov 7 38°F Above 36°F · Light Rain Likely
- Sun, Nov 8 32°F Freeze · Light Rain Likely then Chance Rain And Snow
- Mon, Nov 9 30°F Freeze · Slight Chance Rain And Snow then Mostly Cloudy
- Tue, Nov 10 31°F Freeze · Slight Chance Light Rain
- Wed, Nov 11 26°F Hard freeze · Mostly 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 Caribou
The median first fall hard-freeze date (28°F) is October 12, from NOAA’s 1991–2020 Climate Normals at Caribou Municipal Airport. 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 | May 7 · May 24 · Jun 7 | Sep 6 · Sep 19 · Oct 1 | 117 days |
| 32°F freeze | Apr 27 · May 7 · May 24 | Sep 17 · Oct 1 · Oct 14 | 143 days |
| 28°F hard freeze | Apr 15 · Apr 26 · May 7 | Sep 29 · Oct 12 · Oct 30 | 167 days |
Average high temperature by month
1991–2020 normals at Caribou Municipal Airport
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 Caribou, ME come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Caribou Municipal Airport (station USW00014607, elevation 624 ft), 4.5 mi from Caribou. 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 Caribou
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Presque Isle, ME | 11 mi | May 14 | Sep 26 |
| Old Town, ME | 135 mi | May 13 | Sep 28 |
| Bangor, ME | 145 mi | May 4 | Oct 4 |
| Brewer, ME | 147 mi | May 4 | Oct 4 |
| Ellsworth, ME | 158 mi | May 8 | Oct 9 |
| Belfast, ME | 175 mi | May 7 | Oct 5 |
| Waterville, ME | 179 mi | May 2 | Oct 10 |
| Augusta, ME | 193 mi | Apr 27 | Oct 16 |
| Rockland, ME | 196 mi | Apr 27 | Oct 19 |
| Gardiner, ME | 203 mi | May 1 | Oct 11 |
Frequently asked questions
When is the last frost in Caribou?
On average, the last spring frost (32°F) in Caribou is around May 7. In about 1 year in 10 it comes after May 24, and in 9 years in 10 it comes after April 27.
When is the first frost in Caribou?
The first fall frost (32°F) usually arrives around October 1. There’s a 10% chance of a freeze by September 17 and a 90% chance by October 14.
Can it frost in Caribou 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 24.
What growing zone is Caribou?
Caribou is in USDA Plant Hardiness Zone 4a (average annual extreme minimum temperature −30 to −25°F), based on the 2023 USDA map for ZIP code 04742. See growing zones in Maine.
More: all Maine frost dates · Maine growing zones · frost vs. freeze