Frost dates 2026–2027

Frost dates for Bethel Park, Pennsylvania

Median (50% chance) dates of the last and first 32°F frost, from NOAA 1991–2020 climate normals at Pittsburgh Allegheny County Airport, 6.4 mi away (close match).

Last spring frostApr 18
First fall frostOct 28
193 frost-free days
Last spring frostApr 181 year in 10 after May 6
First fall frostOct 281 year in 10 by Oct 14
Growing season193 daysbetween median 32°F dates
Hardiness zoneZone 6b−5 to 0°F average extreme low

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Will it freeze in Bethel Park in the next 7 nights?

No overnight lows at or below 32°F are forecast in Bethel Park during the next 7 nights in the available NWS frost forecast.

Tonight: forecast low 48°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.

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 Bethel Park

The median first fall hard-freeze date (28°F) is November 8, from NOAA’s 1991–2020 Climate Normals at Pittsburgh Allegheny County Airport. This is the 50% probability date, not a forecast for this year.

TemperatureLast 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 16 · Apr 29 · May 17 Oct 4 · Oct 17 · Oct 29 169 days
32°F freeze Apr 2 · Apr 18 · May 6 Oct 14 · Oct 28 · Nov 10 193 days
28°F hard freeze Mar 23 · Apr 5 · Apr 21 Oct 28 · Nov 8 · Nov 22 216 days
NOAA NCEI U.S. Climate Normals 1991–2020, station USW00014762. How to read these probabilities.

Average high temperature by month

1991–2020 normals at Pittsburgh Allegheny County 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 Bethel Park, PA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Pittsburgh Allegheny County Airport (station USW00014762, elevation 1,248 ft), 6.4 mi from Bethel Park. 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 Bethel Park

CityDistanceLast spring frostFirst fall frost
Castle Shannon, PA 3.1 mi Apr 18 Oct 28
Whitehall, PA 3.7 mi Apr 18 Oct 28
Mount Lebanon, PA 3.7 mi Apr 18 Oct 28
Pleasant Hills, PA 4.3 mi Apr 18 Oct 28
Brentwood, PA 5.0 mi Apr 18 Oct 28
Dormont, PA 5.0 mi Apr 18 Oct 28
Jefferson Hills, PA 5.0 mi Apr 18 Oct 28
Baldwin, PA 6.2 mi Apr 18 Oct 28
Carnegie, PA 6.2 mi Apr 24 Oct 27
West Mifflin, PA 7.5 mi Apr 18 Oct 28

Frequently asked questions

When is the last frost in Bethel Park?

On average, the last spring frost (32°F) in Bethel Park is around April 18. In about 1 year in 10 it comes after May 6, and in 9 years in 10 it comes after April 2.

When is the first frost in Bethel Park?

The first fall frost (32°F) usually arrives around October 28. There’s a 10% chance of a freeze by October 14 and a 90% chance by November 10.

Can it frost in Bethel Park 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 Bethel Park?

Bethel Park 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 15102. See growing zones in Pennsylvania.

More: all Pennsylvania frost dates · Pennsylvania growing zones · UV index today in Bethel Park · frost vs. freeze