USDA Hardiness Zone 6a
Frost Dates for 16145 — Sandy Lake, Pennsylvania
NOAA 1991–2020 normals from Franklin, PA (1,015 ft), 13 miles east.
Updated
In Sandy Lake, the last spring frost (32°F) is around May 2 in half of years and has passed by May 20 in nine years out of ten. The first fall frost comes around October 23, as early as October 8 one year in ten, leaving a typical freeze-free season of 171 days (NOAA, Franklin, PA).
- Last spring frost
- May 2
- First fall frost
- October 23
- Growing season
- 171 days
- Hardiness zone
- 6a
50% probability
50% probability
freeze-free, 50%
-10 to -5°F (-23.3 to -20.6°C) coldest night
- First snow
- November 24
- Last snow
- March 26
- Winters with snow
- 100%
- Snow per year
- 53.7"
median, 1991–2020
median, 1991–2020
29 of 29 observed
NOAA normal
Frost risk by date in Sandy Lake
Half of springs at Franklin, PA see their last 32°F night by May 2; only one in ten is past it by April 20, and one in ten still has one after May 20. Planting tender crops after May 9 leaves a 30% risk of a frost on them, after May 15 20%, and after May 20 10%. The 18 days between the even-odds date and the one-in-ten date is wider than at 70% of the 176 Pennsylvania stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 23 in half of years, as early as October 8 one year in ten, and holds off past November 4 one year in ten. A hard freeze of 28°F follows 11 days later, around November 3; in spring the one-in-ten date for 28°F is May 8, 12 days before the 32°F one. The freeze-free season lasts 171 days in a typical year, shorter than at 57% of the 176 Pennsylvania stations; it reaches 190 days one year in ten and falls short of 153 one year in ten. On average 142 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 13, and return around October 9. Severe cold of 16°F or below comes every winter, usually between December 7 and March 17.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 29 | May 3 | May 7 | May 10 | May 13 | May 18 | May 21 | May 24 | May 28 |
| 32°F | Apr 20 | Apr 23 | Apr 27 | Apr 30 | May 2 | May 6 | May 9 | May 15 | May 20 |
| 28°F | Apr 7 | Apr 12 | Apr 16 | Apr 19 | Apr 21 | Apr 24 | Apr 28 | May 2 | May 8 |
| 24°F | Mar 25 | Mar 31 | Apr 2 | Apr 5 | Apr 7 | Apr 10 | Apr 13 | Apr 16 | Apr 21 |
| 20°F | Mar 11 | Mar 16 | Mar 21 | Mar 24 | Mar 28 | Mar 31 | Apr 2 | Apr 5 | Apr 9 |
| 16°F | Mar 2 | Mar 7 | Mar 11 | Mar 14 | Mar 17 | Mar 19 | Mar 23 | Mar 27 | Mar 31 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 29 | Oct 1 | Oct 4 | Oct 7 | Oct 9 | Oct 12 | Oct 15 | Oct 18 | Oct 23 |
| 32°F | Oct 8 | Oct 14 | Oct 17 | Oct 20 | Oct 23 | Oct 25 | Oct 29 | Nov 1 | Nov 4 |
| 28°F | Oct 22 | Oct 27 | Oct 30 | Nov 1 | Nov 3 | Nov 6 | Nov 8 | Nov 11 | Nov 15 |
| 24°F | Nov 2 | Nov 6 | Nov 9 | Nov 11 | Nov 14 | Nov 17 | Nov 19 | Nov 23 | Nov 29 |
| 20°F | Nov 10 | Nov 15 | Nov 18 | Nov 22 | Nov 25 | Nov 28 | Dec 1 | Dec 7 | Dec 14 |
| 16°F | Nov 17 | Nov 25 | Nov 30 | Dec 3 | Dec 7 | Dec 11 | Dec 16 | Dec 22 | Dec 28 |
Freeze probabilities 1991–2020 at Franklin, 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 16145 →Compare Sandy Lake with another place →
Weather by month in Sandy Lake
July is the warmest month at Franklin, PA, averaging 83°F by day and 60°F at night; January is the coldest at 34°F and 18°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 55% of years.
Warmth for growing adds up to 2,697 growing degree days a year (base 50°F), fewer than at 66% of the 176 Pennsylvania stations. 33% of them (898) have built up by the end of June, and July adds the most, 656. Precipitation totals 46.5 inches a year, most in July (5.3") and least in February (2.7"); May to September bring 48% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 34 | 18 | 3.3 | 100% | 28 | 1 |
| Feb | 36 | 19 | 2.7 | 100% | 26 | 1 |
| Mar | 46 | 25 | 3.4 | 100% | 24 | 16 |
| Apr | 60 | 35 | 4.2 | 100% | 13 | 80 |
| May | 71 | 46 | 4.0 | 55% | 2 | 287 |
| Jun | 79 | 56 | 4.9 | 0% | 0 | 513 |
| Jul | 83 | 60 | 5.3 | 0% | 0 | 656 |
| Aug | 81 | 58 | 4.2 | 0% | 0 | 612 |
| Sep | 74 | 52 | 3.9 | 0% | 0 | 392 |
| Oct | 61 | 41 | 3.8 | 79% | 5 | 120 |
| Nov | 49 | 32 | 3.4 | 100% | 18 | 18 |
| Dec | 38 | 24 | 3.4 | 100% | 26 | 3 |
Monthly normals 1991–2020 at Franklin, PA (1,015 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, Mercer, PA, 14 miles southwest of Sandy Lake and 205 feet higher, has a last frost 13 days later (May 15), a first frost 20 days earlier (October 3), a season 31 days shorter.
When it snows in Sandy Lake, Pennsylvania
The first measurable snow (0.1 inch or more) in Sandy Lake usually arrives around November 24, and the last of the season around March 26. Those are the middle dates across the winters of 1991–2020 at Franklin, PA, 13 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 37 days after the last snow.
Planting calendar for 16145
| When | What to do |
|---|---|
| February 21 – March 7 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 7 – March 21 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| April 4 – April 18 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| May 2 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 31 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 9 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 23 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 16145 is 13 miles from Franklin, PA, which stands at 1,015 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 4 other ZIP codes share the station; its figures are presented in full for 16301 (Oil City). The 2023 USDA Plant Hardiness Zone Map lists ZIP 16145 in zone 6a, the band where the coldest night of the year averaged -10 to -5°F (-23.3 to -20.6°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.