USDA Hardiness Zone 7a
Frost Dates for 17007 — Boiling Springs, Pennsylvania
NOAA 1991–2020 normals from Carlisle Wtp, PA (430 ft), 6 miles northwest.
Updated
In Boiling Springs, the last spring frost (32°F) is around April 23 in half of years and has passed by May 9 in nine years out of ten. The first fall frost comes around October 18, as early as October 4 one year in ten, leaving a typical freeze-free season of 177 days (NOAA, Carlisle Wtp, PA).
- Last spring frost
- April 23
- First fall frost
- October 18
- Growing season
- 177 days
- Hardiness zone
- 7a
50% probability
50% probability
freeze-free, 50%
0 to 5°F (-17.8 to -15.0°C) coldest night
- First snow
- December 11
- Last snow
- March 19
- Winters with snow
- 97%
- Snow per year
- 30.7"
median, 1991–2020
median, 1991–2020
28 of 29 observed
NOAA normal
Frost risk by date in Boiling Springs
Half of springs at Carlisle Wtp, PA see their last 32°F night by April 23; only one in ten is past it by April 9, and one in ten still has one after May 9. Planting tender crops after April 30 leaves a 30% risk of a frost on them, after May 3 20%, and after May 9 10%. The 16 days between the even-odds date and the one-in-ten date is narrower than at 51% of the 176 Pennsylvania stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 18 in half of years, as early as October 4 one year in ten, and holds off past November 2 one year in ten. A hard freeze of 28°F follows 14 days later, around November 1; in spring the one-in-ten date for 28°F is April 24, 15 days before the 32°F one. The freeze-free season lasts 177 days in a typical year, longer than at 56% of the 176 Pennsylvania stations; it reaches 198 days one year in ten and falls short of 155 one year in ten. On average 127 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 10 days longer, to about May 3, and return around October 6. Severe cold of 16°F or below comes every winter, usually between December 9 and March 6.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 20 | Apr 25 | Apr 28 | Apr 30 | May 3 | May 6 | May 10 | May 14 | May 19 |
| 32°F | Apr 9 | Apr 14 | Apr 17 | Apr 20 | Apr 23 | Apr 26 | Apr 30 | May 3 | May 9 |
| 28°F | Mar 28 | Apr 1 | Apr 4 | Apr 7 | Apr 10 | Apr 13 | Apr 15 | Apr 18 | Apr 24 |
| 24°F | Mar 13 | Mar 18 | Mar 22 | Mar 26 | Mar 29 | Mar 31 | Apr 2 | Apr 5 | Apr 10 |
| 20°F | Feb 28 | Mar 6 | Mar 9 | Mar 13 | Mar 16 | Mar 19 | Mar 23 | Mar 26 | Mar 31 |
| 16°F | Feb 17 | Feb 24 | Feb 28 | Mar 2 | Mar 6 | Mar 9 | Mar 12 | Mar 16 | Mar 22 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 25 | Sep 30 | Oct 2 | Oct 4 | Oct 6 | Oct 9 | Oct 12 | Oct 16 | Oct 21 |
| 32°F | Oct 4 | Oct 8 | Oct 11 | Oct 15 | Oct 18 | Oct 21 | Oct 24 | Oct 29 | Nov 2 |
| 28°F | Oct 14 | Oct 20 | Oct 24 | Oct 28 | Nov 1 | Nov 3 | Nov 5 | Nov 9 | Nov 14 |
| 24°F | Oct 28 | Nov 1 | Nov 5 | Nov 8 | Nov 12 | Nov 15 | Nov 18 | Nov 22 | Nov 29 |
| 20°F | Nov 9 | Nov 14 | Nov 18 | Nov 22 | Nov 27 | Nov 30 | Dec 3 | Dec 6 | Dec 15 |
| 16°F | Nov 21 | Nov 29 | Dec 2 | Dec 5 | Dec 9 | Dec 14 | Dec 19 | Dec 24 | Dec 30 |
Freeze probabilities 1991–2020 at Carlisle Wtp, 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 17007 →Compare Boiling Springs with another place →
Weather by month in Boiling Springs
July is the warmest month at Carlisle Wtp, PA, averaging 86°F by day and 63°F at night; January is the coldest at 38°F and 21°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 26% of years.
Warmth for growing adds up to 3,156 growing degree days a year (base 50°F), more than at 65% of the 176 Pennsylvania stations. 34% of them (1,071) have built up by the end of June, and July adds the most, 744. Precipitation totals 48.2 inches a year, most in July (5.5") and least in February (2.6"); May to September bring 49% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 38 | 21 | 3.1 | 100% | 28 | 1 |
| Feb | 41 | 22 | 2.6 | 100% | 25 | 3 |
| Mar | 50 | 29 | 4.1 | 100% | 21 | 22 |
| Apr | 63 | 39 | 3.8 | 98% | 7 | 113 |
| May | 73 | 49 | 4.7 | 26% | <1 | 338 |
| Jun | 81 | 59 | 4.4 | 0% | 0 | 594 |
| Jul | 86 | 63 | 5.5 | 0% | 0 | 744 |
| Aug | 84 | 61 | 4.0 | 0% | 0 | 691 |
| Sep | 77 | 53 | 5.0 | 2% | 0 | 460 |
| Oct | 66 | 42 | 4.3 | 85% | 4 | 165 |
| Nov | 54 | 32 | 3.1 | 100% | 17 | 24 |
| Dec | 42 | 25 | 3.6 | 100% | 25 | 2 |
Monthly normals 1991–2020 at Carlisle Wtp, PA (430 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, Bloserville 1 N, PA, 15 miles northwest of Boiling Springs and 270 feet higher, has a last frost 5 days earlier (April 18), a first frost 8 days later (October 26), a season 14 days longer.
When it snows in Boiling Springs, Pennsylvania
The first measurable snow (0.1 inch or more) in Boiling Springs usually arrives around December 11, and the last of the season around March 19. Those are the middle dates across the winters of 1991–2020 at Pine Grove Furnace, PA, 12.5 miles away: half of years saw snow earlier, half later. Snow fell in 97% of those winters. The last 32°F night of spring typically comes 35 days after the last snow.
Planting calendar for 17007
| When | What to do |
|---|---|
| February 12 – February 26 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 26 – March 12 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 26 – April 9 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 23 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 26 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 4 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 18 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 17007 is 6 miles from Carlisle Wtp, PA, which stands at 430 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 6 other ZIP codes share the station; its figures are presented in full for 17013 (Carlisle). The 2023 USDA Plant Hardiness Zone Map lists ZIP 17007 in zone 7a, the band where the coldest night of the year averaged 0 to 5°F (-17.8 to -15.0°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.