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Will it freeze in Penn Hills in the next 7 nights?
No overnight lows at or below 32°F are forecast in Penn Hills during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 47°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM EST to Fri, Nov 6, 6:00 AM EST.
3 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 47°F Above 36°F · Partly Cloudy
- Fri, Nov 6 39°F Above 36°F · Chance Rain Showers then Mostly Cloudy
- Sat, Nov 7 37°F Above 36°F · Chance Light Rain then Mostly Cloudy
- Sun, Nov 8 34°F Frost possible · Partly Cloudy
- Mon, Nov 9 37°F Above 36°F · Mostly Clear
- Tue, Nov 10 35°F Frost possible · Mostly Clear
- Wed, Nov 11 34°F Frost possible · 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 Penn Hills
The median first fall hard-freeze date (28°F) is November 11, from NOAA’s 1991–2020 Climate Normals at Acmetonia Lock 3. 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 13 · Apr 29 · May 17 | Oct 7 · Oct 20 · Nov 1 | 172 days |
| 32°F freeze | Mar 31 · Apr 16 · May 4 | Oct 18 · Nov 1 · Nov 13 | 197 days |
| 28°F hard freeze | Mar 19 · Apr 3 · Apr 19 | Nov 1 · Nov 11 · Nov 25 | 222 days |
Average high temperature by month
1991–2020 normals at Acmetonia Lock 3
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 Penn Hills, PA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Acmetonia Lock 3 (station USC00360022, elevation 748 ft), 4.0 mi from Penn Hills. 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 Penn Hills
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Oakmont, PA | 3.1 mi | Apr 16 | Nov 1 |
| Wilkinsburg, PA | 3.1 mi | Apr 5 | Nov 10 |
| Forest Hills, PA | 3.7 mi | Apr 5 | Nov 10 |
| Plum, PA | 4.3 mi | Apr 16 | Nov 1 |
| Fox Chapel, PA | 4.3 mi | Apr 16 | Nov 1 |
| Swissvale, PA | 5.0 mi | Apr 5 | Nov 10 |
| Monroeville, PA | 5.0 mi | Apr 22 | Oct 25 |
| Munhall, PA | 6.8 mi | Apr 5 | Nov 10 |
| Duquesne, PA | 7.5 mi | Apr 5 | Nov 10 |
| New Kensington, PA | 7.5 mi | Apr 16 | Nov 2 |
Frequently asked questions
When is the last frost in Penn Hills?
On average, the last spring frost (32°F) in Penn Hills is around April 16. In about 1 year in 10 it comes after May 4, and in 9 years in 10 it comes after March 31.
When is the first frost in Penn Hills?
The first fall frost (32°F) usually arrives around November 1. There’s a 10% chance of a freeze by October 18 and a 90% chance by November 13.
Can it frost in Penn Hills 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 29.
What growing zone is Penn Hills?
Penn Hills is in USDA Plant Hardiness Zone 6b (average annual extreme minimum temperature −5 to 0°F), based on the 2023 USDA map for ZIP code 15147. See growing zones in Pennsylvania.
More: all Pennsylvania frost dates · Pennsylvania growing zones · UV index today in Penn Hills · frost vs. freeze