USDA Hardiness Zone 7a
Frost Dates for 19363 — Oxford, Pennsylvania
NOAA 1991–2020 normals from Octoraro Lake, PA (260 ft), 4 miles west.
Updated
In Oxford, the last spring frost (32°F) is around April 26 in half of years and has passed by May 10 in nine years out of ten. The first fall frost comes around October 22, as early as October 9 one year in ten, leaving a typical freeze-free season of 179 days (NOAA, Octoraro Lake, PA).
- Last spring frost
- April 26
- First fall frost
- October 22
- Growing season
- 179 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 9
- Last snow
- March 12
- Winters with snow
- 67%
- Snow per year
- 18.1"
median, 1991–2020
median, 1991–2020
18 of 27 observed
NOAA normal
Frost risk by date in Oxford
Half of springs at Octoraro Lake, PA see their last 32°F night by April 26; only one in ten is past it by April 9, and one in ten still has one after May 10. Planting tender crops after May 2 leaves a 30% risk of a frost on them, after May 5 20%, and after May 10 10%. The 14 days between the even-odds date and the one-in-ten date is narrower than at 86% of the 176 Pennsylvania stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 22 in half of years, as early as October 9 one year in ten, and holds off past November 3 one year in ten. A hard freeze of 28°F follows 9 days later, around October 31; in spring the one-in-ten date for 28°F is April 30, 10 days before the 32°F one. The freeze-free season lasts 179 days in a typical year, longer than at 63% of the 176 Pennsylvania stations; it reaches 198 days one year in ten and falls short of 159 one year in ten. On average 125 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 8 days longer, to about May 4, and return around October 13. Severe cold of 16°F or below comes every winter, usually between December 11 and March 7.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 21 | Apr 26 | Apr 29 | May 2 | May 4 | May 8 | May 11 | May 15 | May 19 |
| 32°F | Apr 9 | Apr 15 | Apr 19 | Apr 22 | Apr 26 | Apr 29 | May 2 | May 5 | May 10 |
| 28°F | Mar 26 | Mar 31 | Apr 3 | Apr 6 | Apr 11 | Apr 14 | Apr 18 | Apr 23 | Apr 30 |
| 24°F | Mar 11 | Mar 17 | Mar 21 | Mar 25 | Mar 28 | Mar 31 | Apr 3 | Apr 6 | Apr 15 |
| 20°F | Feb 27 | Mar 4 | Mar 9 | Mar 14 | Mar 17 | Mar 21 | Mar 24 | Mar 28 | Apr 2 |
| 16°F | Feb 16 | Feb 24 | Feb 28 | Mar 2 | Mar 7 | Mar 11 | Mar 15 | Mar 19 | Mar 26 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 1 | Oct 4 | Oct 7 | Oct 10 | Oct 13 | Oct 15 | Oct 18 | Oct 21 | Oct 25 |
| 32°F | Oct 9 | Oct 13 | Oct 16 | Oct 19 | Oct 22 | Oct 24 | Oct 27 | Oct 30 | Nov 3 |
| 28°F | Oct 17 | Oct 22 | Oct 25 | Oct 28 | Oct 31 | Nov 2 | Nov 4 | Nov 8 | Nov 13 |
| 24°F | Oct 26 | Nov 1 | Nov 4 | Nov 7 | Nov 10 | Nov 14 | Nov 17 | Nov 22 | Nov 30 |
| 20°F | Nov 5 | Nov 12 | Nov 18 | Nov 22 | Nov 27 | Dec 1 | Dec 5 | Dec 10 | Dec 18 |
| 16°F | Nov 20 | Nov 29 | Dec 2 | Dec 7 | Dec 11 | Dec 15 | Dec 20 | Dec 25 | Jan 2 |
Freeze probabilities 1991–2020 at Octoraro Lake, 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 19363 →Compare Oxford with another place →
Frost risk through the year in Oxford
In Oxford, the spring curve drops under 10% on May 10 and the fall curve passes 10% on October 9, 152 days later; that gap is longer than at 69% of the 176 Pennsylvania stations with frost dates. The spring risk falls from 90% to 10% over 31 days (April 9 to May 10) and the fall risk climbs from 10% to 90% over 25 days (October 9 to November 3): both ends of the season vary about as much. At Avondale 2 N, PA, 11 miles northeast, the same gap runs from May 3 to October 11, 9 days longer.
| Planted on | Another 32°F night | 28°F night |
|---|---|---|
| Apr 12 | 85% | 47% |
| Apr 19 | 70% | 28% |
| Apr 2650% date | 50% | 16% |
| May 3 | 27% | under 10% |
| May 10 | under 10% | under 10% |
| May 17 | under 10% | under 10% |
Weather by month in Oxford
July is the warmest month at Octoraro Lake, PA, averaging 85°F by day and 65°F at night; January is the coldest at 39°F and 22°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 34% of years.
Warmth for growing adds up to 3,280 growing degree days a year (base 50°F), more than at 78% of the 176 Pennsylvania stations. 34% of them (1,110) have built up by the end of June, and July adds the most, 767. Precipitation totals 48.5 inches a year, most in September (5.2") and least in February (2.9"); May to September bring 46% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 39 | 22 | 3.5 | 100% | 26 | 2 |
| Feb | 42 | 23 | 2.9 | 100% | 25 | 3 |
| Mar | 51 | 31 | 4.2 | 100% | 19 | 24 |
| Apr | 63 | 40 | 3.8 | 96% | 8 | 123 |
| May | 72 | 50 | 3.6 | 34% | 1 | 356 |
| Jun | 80 | 60 | 4.5 | 0% | 0 | 603 |
| Jul | 85 | 65 | 4.5 | 0% | 0 | 767 |
| Aug | 83 | 63 | 4.7 | 0% | 0 | 710 |
| Sep | 76 | 56 | 5.2 | 0% | 0 | 475 |
| Oct | 65 | 44 | 4.1 | 82% | 5 | 180 |
| Nov | 53 | 33 | 3.4 | 100% | 17 | 31 |
| Dec | 43 | 27 | 4.1 | 100% | 25 | 7 |
Monthly normals 1991–2020 at Octoraro Lake, PA (260 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, Avondale 2 N, PA, 11 miles northeast of Oxford, has a last frost 7 days earlier (April 19), a first frost 4 days later (October 26), a season 10 days longer.
When it snows in Oxford, Pennsylvania
The first measurable snow (0.1 inch or more) in Oxford usually arrives around December 9, and the last of the season around March 12. Those are the middle dates across the winters of 1991–2020 at Octoraro Lake, PA, 3.8 miles away: half of years saw snow earlier, half later. Snow fell in 67% of those winters. The last 32°F night of spring typically comes 45 days after the last snow.
Planting calendar for 19363
| When | What to do |
|---|---|
| February 15 – March 1 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 1 – March 15 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 29 – April 12 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 26 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 30 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 8 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 22 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 19363 is 4 miles from Octoraro Lake, PA, which stands at 260 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 6 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 19363 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.