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Will it freeze in Carnegie in the next 7 nights?
No overnight lows at or below 32°F are forecast in Carnegie during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 49°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM EST to Fri, Nov 6, 6:00 AM EST.
1 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 49°F Above 36°F · Partly Cloudy
- Fri, Nov 6 40°F Above 36°F · Chance Light Rain
- Sat, Nov 7 39°F Above 36°F · Chance Light Rain then Mostly Cloudy
- Sun, Nov 8 36°F Frost possible · Mostly Clear
- Mon, Nov 9 39°F Above 36°F · Mostly Clear
- Tue, Nov 10 38°F Above 36°F · Mostly Clear
- Wed, Nov 11 37°F Above 36°F · 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 Carnegie
The median first fall hard-freeze date (28°F) is November 5, from NOAA’s 1991–2020 Climate Normals at Emsworth L/d Ohio Rvr. 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 20 · May 5 · May 21 | Oct 2 · Oct 16 · Oct 28 | 163 days |
| 32°F freeze | Apr 9 · Apr 24 · May 11 | Oct 13 · Oct 27 · Nov 7 | 186 days |
| 28°F hard freeze | Mar 28 · Apr 12 · Apr 26 | Oct 24 · Nov 5 · Nov 20 | 209 days |
Average high temperature by month
1991–2020 normals at Emsworth L/d Ohio Rvr
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 Carnegie, PA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Emsworth L/d Ohio Rvr (station USC00362574, elevation 717 ft), 6.6 mi from Carnegie. 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 Carnegie
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Crafton, PA | 1.9 mi | Apr 24 | Oct 27 |
| Dormont, PA | 2.5 mi | Apr 18 | Oct 28 |
| Mount Lebanon, PA | 3.1 mi | Apr 18 | Oct 28 |
| McKees Rocks, PA | 4.3 mi | Apr 24 | Oct 27 |
| Castle Shannon, PA | 4.3 mi | Apr 18 | Oct 28 |
| Whitehall, PA | 6.2 mi | Apr 18 | Oct 28 |
| Bellevue, PA | 6.2 mi | Apr 24 | Oct 27 |
| Pittsburgh, PA | 6.2 mi | Apr 18 | Oct 28 |
| Brentwood, PA | 6.2 mi | Apr 18 | Oct 28 |
| Bethel Park, PA | 6.2 mi | Apr 18 | Oct 28 |
Frequently asked questions
When is the last frost in Carnegie?
On average, the last spring frost (32°F) in Carnegie is around April 24. In about 1 year in 10 it comes after May 11, and in 9 years in 10 it comes after April 9.
When is the first frost in Carnegie?
The first fall frost (32°F) usually arrives around October 27. There’s a 10% chance of a freeze by October 13 and a 90% chance by November 7.
Can it frost in Carnegie 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 5.
What growing zone is Carnegie?
Carnegie 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 15106. See growing zones in Pennsylvania.
More: all Pennsylvania frost dates · Pennsylvania growing zones · frost vs. freeze