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Will it freeze in Westbrook 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 58°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 58°F Above 36°F · Mostly Cloudy then Slight Chance Light Rain
- Fri, Nov 6 49°F Above 36°F · Light Rain
- Sat, Nov 7 38°F Above 36°F · Light Rain Likely
- Sun, Nov 8 32°F Freeze · Partly Cloudy
- Mon, Nov 9 29°F Freeze · Partly Cloudy
- Tue, Nov 10 31°F Freeze · Partly Cloudy
- Wed, Nov 11 23°F Hard freeze · 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 Westbrook
The median first fall hard-freeze date (28°F) is October 27, from NOAA’s 1991–2020 Climate Normals at Portland Intl Jetport. 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 28 · May 7 · May 20 | Sep 24 · Oct 4 · Oct 17 | 149 days |
| 32°F freeze | Apr 16 · Apr 26 · May 7 | Oct 2 · Oct 15 · Oct 30 | 170 days |
| 28°F hard freeze | Apr 3 · Apr 14 · Apr 25 | Oct 14 · Oct 27 · Nov 9 | 195 days |
Average high temperature by month
1991–2020 normals at Portland Intl Jetport
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 Westbrook, ME come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Portland Intl Jetport (station USW00014764, elevation 45 ft), 4.8 mi from Westbrook. 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 Westbrook
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Portland, ME | 5.6 mi | Apr 26 | Oct 15 |
| South Portland, ME | 6.2 mi | Apr 26 | Oct 15 |
| Saco, ME | 13 mi | Apr 26 | Oct 15 |
| Biddeford, ME | 19 mi | May 9 | Oct 3 |
| Auburn, ME | 27 mi | Apr 25 | Oct 19 |
| Lewiston, ME | 28 mi | Apr 25 | Oct 19 |
| Sanford, ME | 28 mi | May 16 | Sep 30 |
| Bath, ME | 30 mi | May 10 | Oct 6 |
| Somersworth, NH | 41 mi | Apr 30 | Oct 9 |
| Rochester, NH | 42 mi | Apr 30 | Oct 9 |
Frequently asked questions
When is the last frost in Westbrook?
On average, the last spring frost (32°F) in Westbrook is around April 26. In about 1 year in 10 it comes after May 7, and in 9 years in 10 it comes after April 16.
When is the first frost in Westbrook?
The first fall frost (32°F) usually arrives around October 15. There’s a 10% chance of a freeze by October 2 and a 90% chance by October 30.
Can it frost in Westbrook 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 7.
What growing zone is Westbrook?
Westbrook 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 04092. See growing zones in Maine.
More: all Maine frost dates · Maine growing zones · frost vs. freeze