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Frost Dates for Lewisburg, PA

Last spring frost
Apr 26
First fall frost
Oct 20
Growing season
176 days
Hardiness zone
6b

In an average year around Lewisburg, PA, the last spring frost (32°F) is about Apr 26 and the first fall frost is about Oct 20, giving roughly a 176-day growing season. To be safe most years, wait until Apr 13 before setting out tender plants.

Last spring frost

Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.

Last spring frost - Lewisburg, PA
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 21 May 6 Apr 23
Freeze (32°F) May 11 Apr 26 Apr 13
Hard (28°F) Apr 28 Apr 14 Mar 31
Severe (24°F) Apr 15 Apr 2 Mar 17
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 21 May 17 May 12 May 9 May 6 May 3 Apr 30 Apr 27 Apr 23
32°F May 11 May 5 May 2 Apr 29 Apr 26 Apr 23 Apr 20 Apr 17 Apr 13
28°F Apr 28 Apr 23 Apr 19 Apr 16 Apr 14 Apr 10 Apr 8 Apr 4 Mar 31
24°F Apr 15 Apr 10 Apr 6 Apr 4 Apr 2 Mar 30 Mar 27 Mar 23 Mar 17
20°F Apr 4 Apr 1 Mar 28 Mar 25 Mar 21 Mar 18 Mar 15 Mar 10 Mar 6
16°F Mar 26 Mar 20 Mar 17 Mar 14 Mar 10 Mar 7 Mar 5 Feb 28 Feb 22

First fall frost

Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.

First fall frost - Lewisburg, PA
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Sep 25 Oct 7 Oct 21
Freeze (32°F) Oct 5 Oct 20 Nov 1
Hard (28°F) Oct 17 Nov 1 Nov 13
Severe (24°F) Oct 31 Nov 11 Nov 25
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Sep 25 Sep 30 Oct 2 Oct 5 Oct 7 Oct 10 Oct 13 Oct 16 Oct 21
32°F Oct 5 Oct 9 Oct 13 Oct 17 Oct 20 Oct 23 Oct 26 Oct 29 Nov 1
28°F Oct 17 Oct 22 Oct 26 Oct 29 Nov 1 Nov 2 Nov 4 Nov 7 Nov 13
24°F Oct 31 Nov 2 Nov 5 Nov 8 Nov 11 Nov 14 Nov 17 Nov 20 Nov 25
20°F Nov 8 Nov 13 Nov 16 Nov 20 Nov 23 Nov 27 Nov 30 Dec 3 Dec 11
16°F Nov 18 Nov 26 Dec 1 Dec 3 Dec 6 Dec 12 Dec 17 Dec 22 Dec 31

Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.

Where this data comes from

These dates are computed from the nearest official weather station with long-term records: Lewisburg, Pa, about 4 miles away@if(!empty($station['elevation_ft'])), at 500 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.

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How we calculate these dates

Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.

Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.

Frequently asked questions

When is the last frost in Lewisburg, PA?

On average, the last spring frost (32°F) around Lewisburg, PA is about Apr 26. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 13.

When is the first frost in the fall?

The first fall frost around Lewisburg, PA typically arrives about Oct 20. Count back by a crop's days to maturity to find the latest date you can plant it.

When can I plant tomatoes and other tender crops?

Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Apr 26 on average, or Apr 13 to be safe most years.

How long is the growing season here?

The frost-free growing season (between the last spring and first fall 32°F frost) is about 176 days in a typical year.

Are these dates a forecast for this year?

No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.

Local weather for 17837 Planting calendar → Pennsylvania frost dates →

Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026