Last spring frost
Apr 18
Frost Dates for Fort Loudon, PA
First fall frost
Oct 25
Growing season
188 days
Hardiness zone
7a
In an average year around Fort Loudon, PA, the last spring frost (32°F) is about Apr 18 and the first fall frost is about Oct 25, giving roughly a 188-day growing season. To be safe most years, wait until Apr 3 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.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | May 17 | Apr 30 | Apr 16 |
| Freeze (32°F) | May 5 | Apr 18 | Apr 3 |
| Hard (28°F) | Apr 21 | Apr 4 | Mar 21 |
| Severe (24°F) | Apr 6 | Mar 24 | Mar 7 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 17 | May 10 | May 7 | May 3 | Apr 30 | Apr 28 | Apr 25 | Apr 21 | Apr 16 |
| 32°F | May 5 | Apr 30 | Apr 25 | Apr 21 | Apr 18 | Apr 15 | Apr 11 | Apr 8 | Apr 3 |
| 28°F | Apr 21 | Apr 15 | Apr 11 | Apr 7 | Apr 4 | Apr 2 | Mar 30 | Mar 27 | Mar 21 |
| 24°F | Apr 6 | Apr 1 | Mar 30 | Mar 27 | Mar 24 | Mar 21 | Mar 17 | Mar 13 | Mar 7 |
| 20°F | Mar 28 | Mar 23 | Mar 19 | Mar 16 | Mar 12 | Mar 9 | Mar 5 | Mar 1 | Feb 25 |
| 16°F | Mar 18 | Mar 13 | Mar 9 | Mar 5 | Mar 2 | Feb 28 | Feb 23 | Feb 18 | Feb 10 |
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.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Oct 1 | Oct 14 | Oct 28 |
| Freeze (32°F) | Oct 10 | Oct 25 | Nov 8 |
| Hard (28°F) | Oct 23 | Nov 6 | Nov 21 |
| Severe (24°F) | Nov 2 | Nov 18 | Dec 5 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 1 | Oct 5 | Oct 8 | Oct 11 | Oct 14 | Oct 16 | Oct 19 | Oct 22 | Oct 28 |
| 32°F | Oct 10 | Oct 15 | Oct 19 | Oct 22 | Oct 25 | Oct 28 | Nov 1 | Nov 3 | Nov 8 |
| 28°F | Oct 23 | Oct 28 | Nov 1 | Nov 3 | Nov 6 | Nov 8 | Nov 12 | Nov 16 | Nov 21 |
| 24°F | Nov 2 | Nov 7 | Nov 11 | Nov 14 | Nov 18 | Nov 22 | Nov 26 | Dec 1 | Dec 5 |
| 20°F | Nov 14 | Nov 20 | Nov 25 | Nov 29 | Dec 1 | Dec 5 | Dec 9 | Dec 15 | Dec 23 |
| 16°F | Nov 29 | Dec 3 | Dec 8 | Dec 13 | Dec 17 | Dec 22 | Dec 26 | Dec 30 | Jan 7 |
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
@endif These dates are computed from the nearest official weather station with long-term records: Chambersburg 1 Ese, Pa, about 13.3 miles away@if(!empty($station['elevation_ft'])), at 640 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.
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 Fort Loudon, PA?
On average, the last spring frost (32°F) around Fort Loudon, PA is about Apr 18. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 3.
When is the first frost in the fall?
The first fall frost around Fort Loudon, PA typically arrives about Oct 25. 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 18 on average, or Apr 3 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 188 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 17224 Planting calendar → Pennsylvania frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026