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Will it freeze in Clairton in the next 7 nights?
No overnight lows at or below 32°F are forecast in Clairton 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.
5 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 38°F Above 36°F · Chance Light Rain
- Sat, Nov 7 36°F Frost possible · Chance Light Rain then Mostly Cloudy
- Sun, Nov 8 34°F Frost possible · Mostly Clear
- Mon, Nov 9 36°F Frost possible · Mostly Clear
- Tue, Nov 10 35°F Frost possible · Mostly Clear
- Wed, Nov 11 34°F Frost possible · 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 Clairton
The median first fall hard-freeze date (28°F) is November 1, from NOAA’s 1991–2020 Climate Normals at Mckeesport. 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 26 · May 12 · May 27 | Sep 21 · Oct 7 · Oct 24 | 149 days |
| 32°F freeze | Apr 17 · May 2 · May 20 | Oct 1 · Oct 20 · Nov 3 | 170 days |
| 28°F hard freeze | Apr 2 · Apr 20 · May 10 | Oct 10 · Nov 1 · Nov 14 | 194 days |
Average high temperature by month
1991–2020 normals at Mckeesport
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 Clairton, PA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Mckeesport (station USC00365573, elevation 740 ft), 3.3 mi from Clairton. 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 Clairton
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Jefferson Hills, PA | 3.1 mi | Apr 18 | Oct 28 |
| McKeesport, PA | 3.7 mi | May 2 | Oct 20 |
| West Mifflin, PA | 4.3 mi | Apr 18 | Oct 28 |
| Pleasant Hills, PA | 4.3 mi | Apr 18 | Oct 28 |
| Duquesne, PA | 5.6 mi | Apr 5 | Nov 10 |
| White Oak, PA | 5.6 mi | May 2 | Oct 20 |
| Baldwin, PA | 6.2 mi | Apr 18 | Oct 28 |
| Munhall, PA | 6.8 mi | Apr 5 | Nov 10 |
| Whitehall, PA | 6.8 mi | Apr 18 | Oct 28 |
| Brentwood, PA | 6.8 mi | Apr 18 | Oct 28 |
Frequently asked questions
When is the last frost in Clairton?
On average, the last spring frost (32°F) in Clairton is around May 2. In about 1 year in 10 it comes after May 20, and in 9 years in 10 it comes after April 17.
When is the first frost in Clairton?
The first fall frost (32°F) usually arrives around October 20. There’s a 10% chance of a freeze by October 1 and a 90% chance by November 3.
Can it frost in Clairton 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 12.
What growing zone is Clairton?
Clairton 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 15025. See growing zones in Pennsylvania.
More: all Pennsylvania frost dates · Pennsylvania growing zones · frost vs. freeze