Last spring frost
Apr 11
Frost Dates for Montgomeryville, PA
First fall frost
Nov 1
Growing season
205 days
Hardiness zone
7a
In an average year around Montgomeryville, PA, the last spring frost (32°F) is about Apr 11 and the first fall frost is about Nov 1, giving roughly a 205-day growing season. To be safe most years, wait until Mar 29 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 11 | Apr 24 | Apr 10 |
| Freeze (32°F) | Apr 27 | Apr 11 | Mar 29 |
| Hard (28°F) | Apr 12 | Mar 30 | Mar 15 |
| Severe (24°F) | Apr 1 | Mar 19 | Mar 1 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 11 | May 5 | May 1 | Apr 28 | Apr 24 | Apr 21 | Apr 18 | Apr 15 | Apr 10 |
| 32°F | Apr 27 | Apr 21 | Apr 17 | Apr 14 | Apr 11 | Apr 8 | Apr 5 | Apr 1 | Mar 29 |
| 28°F | Apr 12 | Apr 6 | Apr 3 | Apr 1 | Mar 30 | Mar 27 | Mar 24 | Mar 20 | Mar 15 |
| 24°F | Apr 1 | Mar 29 | Mar 25 | Mar 22 | Mar 19 | Mar 16 | Mar 13 | Mar 8 | Mar 1 |
| 20°F | Mar 25 | Mar 19 | Mar 15 | Mar 12 | Mar 8 | Mar 5 | Mar 1 | Feb 25 | Feb 18 |
| 16°F | Mar 15 | Mar 9 | Mar 3 | Feb 28 | Feb 24 | Feb 19 | Feb 13 | Feb 7 | Jan 31 |
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 6 | Oct 21 | Nov 4 |
| Freeze (32°F) | Oct 17 | Nov 1 | Nov 17 |
| Hard (28°F) | Nov 1 | Nov 13 | Dec 1 |
| Severe (24°F) | Nov 7 | Nov 24 | Dec 16 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 6 | Oct 11 | Oct 15 | Oct 18 | Oct 21 | Oct 24 | Oct 28 | Oct 31 | Nov 4 |
| 32°F | Oct 17 | Oct 23 | Oct 27 | Oct 30 | Nov 1 | Nov 4 | Nov 7 | Nov 11 | Nov 17 |
| 28°F | Nov 1 | Nov 4 | Nov 7 | Nov 10 | Nov 13 | Nov 16 | Nov 19 | Nov 24 | Dec 1 |
| 24°F | Nov 7 | Nov 12 | Nov 16 | Nov 20 | Nov 24 | Nov 29 | Dec 2 | Dec 7 | Dec 16 |
| 20°F | Nov 16 | Nov 23 | Nov 30 | Dec 3 | Dec 8 | Dec 12 | Dec 18 | Dec 24 | Dec 31 |
| 16°F | Nov 30 | Dec 6 | Dec 13 | Dec 20 | Dec 25 | Dec 30 | Jan 3 | Jan 8 | Jan 17 |
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: Willow Grove Nas, Pa, about 4.5 miles away@if(!empty($station['elevation_ft'])), at 361 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 Montgomeryville, PA?
On average, the last spring frost (32°F) around Montgomeryville, PA is about Apr 11. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 29.
When is the first frost in the fall?
The first fall frost around Montgomeryville, PA typically arrives about Nov 1. 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 11 on average, or Mar 29 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 205 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 18936 Planting calendar → Pennsylvania frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026