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Will it freeze in Hellertown in the next 7 nights?
The earliest overnight low at or below 32°F in the available NWS frost forecast is Wed, Nov 11: 32°F (Wed, Nov 11, 6:00 PM EST to Thu, Nov 12, 6:00 AM EST).
Tonight: forecast low 60°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM EST to Fri, Nov 6, 6:00 AM EST.
3 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 60°F Above 36°F · Light Rain
- Fri, Nov 6 47°F Above 36°F · Partly Cloudy
- Sat, Nov 7 41°F Above 36°F · Partly Cloudy
- Sun, Nov 8 37°F Above 36°F · Mostly Clear
- Mon, Nov 9 36°F Frost possible · Mostly Clear
- Tue, Nov 10 36°F Frost possible · Mostly Clear
- Wed, Nov 11 32°F Freeze · 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 Hellertown
The median first fall hard-freeze date (28°F) is November 3, from NOAA’s 1991–2020 Climate Normals at Springtown 1 Nne. 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 19 · May 2 · May 18 | Sep 30 · Oct 10 · Oct 26 | 161 days |
| 32°F freeze | Apr 8 · Apr 21 · May 6 | Oct 7 · Oct 22 · Nov 6 | 184 days |
| 28°F hard freeze | Mar 29 · Apr 8 · Apr 23 | Oct 18 · Nov 3 · Nov 17 | 208 days |
Average high temperature by month
1991–2020 normals at Springtown 1 Nne
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 Hellertown, PA come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Springtown 1 Nne (station USC00368400, elevation 860 ft), 3.2 mi from Hellertown. 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 Hellertown
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Bethlehem, PA | 3.7 mi | Apr 20 | Oct 24 |
| Allentown, PA | 7.5 mi | Apr 20 | Oct 24 |
| Catasauqua, PA | 8.1 mi | Apr 20 | Oct 24 |
| Wilson, PA | 8.7 mi | Apr 18 | Oct 25 |
| Emmaus, PA | 8.7 mi | Apr 20 | Oct 24 |
| Easton, PA | 9.3 mi | Apr 18 | Oct 25 |
| Quakertown, PA | 9.9 mi | Apr 26 | Oct 17 |
| Northampton, PA | 11 mi | Apr 20 | Oct 24 |
| Nazareth, PA | 11 mi | Apr 18 | Oct 25 |
| Phillipsburg, NJ | 11 mi | Apr 18 | Oct 25 |
Frequently asked questions
When is the last frost in Hellertown?
On average, the last spring frost (32°F) in Hellertown is around April 21. In about 1 year in 10 it comes after May 6, and in 9 years in 10 it comes after April 8.
When is the first frost in Hellertown?
The first fall frost (32°F) usually arrives around October 22. There’s a 10% chance of a freeze by October 7 and a 90% chance by November 6.
Can it frost in Hellertown 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 2.
What growing zone is Hellertown?
Hellertown is in USDA Plant Hardiness Zone 7a (average annual extreme minimum temperature 0 to 5°F), based on the 2023 USDA map for ZIP code 18015. See growing zones in Pennsylvania.
More: all Pennsylvania frost dates · Pennsylvania growing zones · frost vs. freeze