USDA Hardiness Zone 5b
Frost Dates for 16701 — Bradford, Pennsylvania
NOAA 1991–2020 normals from Bradford 4SW Rsch 5, PA (1,660 ft), 4 miles southwest.
Updated
In Bradford, the last spring frost (32°F) is around May 18 in half of years and has passed by May 31 in nine years out of ten. The first fall frost comes around October 4, as early as September 21 one year in ten, leaving a typical freeze-free season of 140 days (NOAA, Bradford 4SW Rsch 5, PA).
- Last spring frost
- May 18
- First fall frost
- October 4
- Growing season
- 140 days
- Hardiness zone
- 5b
50% probability
50% probability
freeze-free, 50%
-15 to -10°F (-26.1 to -23.3°C) coldest night
- First snow
- November 8
- Last snow
- April 5
- Winters with snow
- 100%
- Snow per year
- 75.2"
median, 1991–2020
median, 1991–2020
30 of 30 observed
NOAA normal
Frost risk by date in Bradford
Half of springs at Bradford 4SW Rsch 5, PA see their last 32°F night by May 18; only one in ten is past it by April 30, and one in ten still has one after May 31. Planting tender crops after May 24 leaves a 30% risk of a frost on them, after May 27 20%, and after May 31 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 94% of the 176 Pennsylvania stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 4 in half of years, as early as September 21 one year in ten, and holds off past October 19 one year in ten. A hard freeze of 28°F follows 13 days later, around October 17; in spring the one-in-ten date for 28°F is May 23, 8 days before the 32°F one. The freeze-free season lasts 140 days in a typical year, shorter than at 94% of the 176 Pennsylvania stations; it reaches 161 days one year in ten and falls short of 122 one year in ten. On average 169 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 11 days longer, to about May 29, and return around September 24. Severe cold of 16°F or below comes every winter, usually between November 21 and March 31.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 14 | May 21 | May 24 | May 26 | May 29 | May 31 | Jun 3 | Jun 6 | Jun 11 |
| 32°F | Apr 30 | May 6 | May 11 | May 15 | May 18 | May 21 | May 24 | May 27 | May 31 |
| 28°F | Apr 20 | Apr 25 | Apr 28 | Apr 30 | May 4 | May 8 | May 12 | May 17 | May 23 |
| 24°F | Apr 8 | Apr 13 | Apr 17 | Apr 20 | Apr 23 | Apr 26 | Apr 30 | May 4 | May 9 |
| 20°F | Mar 29 | Apr 2 | Apr 3 | Apr 6 | Apr 8 | Apr 11 | Apr 15 | Apr 18 | Apr 25 |
| 16°F | Mar 16 | Mar 21 | Mar 24 | Mar 28 | Mar 31 | Apr 1 | Apr 3 | Apr 6 | Apr 11 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 10 | Sep 16 | Sep 19 | Sep 22 | Sep 24 | Sep 27 | Sep 29 | Oct 2 | Oct 6 |
| 32°F | Sep 21 | Sep 26 | Sep 29 | Oct 1 | Oct 4 | Oct 7 | Oct 10 | Oct 14 | Oct 19 |
| 28°F | Oct 1 | Oct 7 | Oct 11 | Oct 14 | Oct 17 | Oct 21 | Oct 24 | Oct 28 | Nov 2 |
| 24°F | Oct 14 | Oct 21 | Oct 25 | Oct 28 | Oct 31 | Nov 2 | Nov 5 | Nov 8 | Nov 14 |
| 20°F | Oct 29 | Nov 1 | Nov 4 | Nov 7 | Nov 10 | Nov 13 | Nov 17 | Nov 21 | Nov 27 |
| 16°F | Nov 6 | Nov 10 | Nov 14 | Nov 18 | Nov 21 | Nov 25 | Nov 29 | Dec 2 | Dec 8 |
Freeze probabilities 1991–2020 at Bradford 4SW Rsch 5, PA, from NOAA NCEI U.S. Climate Normals. Where a temperature is reached in fewer than 99.5% of years, the dates describe only the years that reach it. Not a forecast.
Frost risk on any date in 16701 →Compare Bradford with another place →
Weather by month in Bradford
July is the warmest month at Bradford 4SW Rsch 5, PA, averaging 79°F by day and 55°F at night; January is the coldest at 31°F and 13°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 89% of years.
Warmth for growing adds up to 2,058 growing degree days a year (base 50°F), fewer than at 95% of the 176 Pennsylvania stations. 33% of them (671) have built up by the end of June, and July adds the most, 530. Precipitation totals 49.6 inches a year, most in July (5.0") and least in February (2.8"); May to September bring 47% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 31 | 13 | 3.8 | 100% | 29 | 1 |
| Feb | 33 | 13 | 2.8 | 100% | 27 | 0 |
| Mar | 42 | 21 | 3.3 | 100% | 27 | 7 |
| Apr | 56 | 32 | 4.2 | 100% | 18 | 50 |
| May | 68 | 42 | 4.5 | 89% | 5 | 209 |
| Jun | 76 | 51 | 4.8 | 8% | 0 | 405 |
| Jul | 79 | 55 | 5.0 | 0% | 0 | 530 |
| Aug | 78 | 54 | 4.6 | 0% | 0 | 487 |
| Sep | 71 | 47 | 4.2 | 35% | 1 | 284 |
| Oct | 59 | 37 | 4.4 | 98% | 12 | 75 |
| Nov | 46 | 28 | 3.9 | 100% | 22 | 10 |
| Dec | 35 | 20 | 4.1 | 100% | 28 | 1 |
Monthly normals 1991–2020 at Bradford 4SW Rsch 5, PA (1,660 ft), NOAA NCEI. "32°F night": chance of at least one in the month. GDD: growing degree days, base 50°F.
Compared with the next station
The nearest other station, Bradford Regional Airport, PA, 10 miles south of Bradford and 457 feet higher, has the same 50% last-frost date, a first frost 3 days earlier (October 1), a season 4 days shorter.
When it snows in Bradford, Pennsylvania
The first measurable snow (0.1 inch or more) in Bradford usually arrives around November 8, and the last of the season around April 5. Those are the middle dates across the winters of 1991–2020 at Bradford 4SW Rsch 5, PA, 4.4 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 43 days after the last snow.
Planting calendar for 16701
| When | What to do |
|---|---|
| March 9 – March 23 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 23 – April 6 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| April 20 – May 4 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| May 18 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 12 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by September 20 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 4 onward | Plant garlic, mulch beds, lift tender bulbsGarlic wants a cold spell; bare soil loses structure over winter. |
The weeks before and after the 50% dates are general rules of thumb, not NOAA figures; a seed packet gives the timing for each variety.
Where these figures come from
ZIP 16701 is 4 miles from Bradford 4SW Rsch 5, PA, which stands at 1,660 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 16701 in zone 5b, the band where the coldest night of the year averaged -15 to -10°F (-26.1 to -23.3°C) over 1991–2020; a zone describes winter lows, not frost dates.
Frost dates across Pennsylvania →
Hardiness zone and temperature range: USDA Plant Hardiness Zone Map 2023 (USDA-ARS, Oregon State University), ZIP-code listing, unchanged. °C converted from °F by this site.
Thirty-year averages, not a forecast: check the forecast before planting out. How stations are matched and which pages are offered to search engines: methodology.