USDA Hardiness Zone 6b
Frost Dates for 16510 — Erie, Pennsylvania
NOAA 1991–2020 normals from Erie International Airport, PA (730 ft), 10 miles west.
Updated
In Erie, the last spring frost (32°F) is around April 26 in half of years and has passed by May 13 in nine years out of ten. The first fall frost comes around November 4, as early as October 21 one year in ten, leaving a typical freeze-free season of 192 days (NOAA, Erie International Airport, PA).
- Last spring frost
- April 26
- First fall frost
- November 4
- Growing season
- 192 days
- Hardiness zone
- 6b
50% probability
50% probability
freeze-free, 50%
-5 to 0°F (-20.6 to -17.8°C) coldest night
- First snow
- November 11
- Last snow
- April 9
- Winters with snow
- 100%
- Snow per year
- 104.3"
median, 1991–2020
median, 1991–2020
29 of 29 observed
NOAA normal
Frost risk by date in Erie
Half of springs at Erie International Airport, PA see their last 32°F night by April 26; only one in ten is past it by April 10, and one in ten still has one after May 13. Planting tender crops after May 2 leaves a 30% risk of a frost on them, after May 6 20%, and after May 13 10%. The 17 days between the even-odds date and the one-in-ten date is wider than at 50% of the 176 Pennsylvania stations behind this site's ZIP pages.
In fall the first 32°F night comes by November 4 in half of years, as early as October 21 one year in ten, and holds off past November 17 one year in ten. A hard freeze of 28°F follows 12 days later, around November 16; in spring the one-in-ten date for 28°F is April 25, 18 days before the 32°F one. The freeze-free season lasts 192 days in a typical year, longer than at 83% of the 176 Pennsylvania stations; it reaches 214 days one year in ten and falls short of 171 one year in ten. On average 111 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 7, and return around October 23. Severe cold of 16°F or below comes every winter, usually between December 22 and March 13.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 23 | Apr 27 | Apr 30 | May 4 | May 7 | May 10 | May 14 | May 17 | May 21 |
| 32°F | Apr 10 | Apr 16 | Apr 20 | Apr 23 | Apr 26 | Apr 29 | May 2 | May 6 | May 13 |
| 28°F | Mar 31 | Apr 3 | Apr 6 | Apr 8 | Apr 11 | Apr 15 | Apr 18 | Apr 21 | Apr 25 |
| 24°F | Mar 16 | Mar 22 | Mar 27 | Mar 30 | Apr 1 | Apr 3 | Apr 5 | Apr 8 | Apr 15 |
| 20°F | Mar 4 | Mar 10 | Mar 14 | Mar 17 | Mar 20 | Mar 23 | Mar 27 | Mar 30 | Apr 2 |
| 16°F | Feb 23 | Mar 1 | Mar 5 | Mar 9 | Mar 13 | Mar 15 | Mar 17 | Mar 20 | Mar 25 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 8 | Oct 14 | Oct 17 | Oct 21 | Oct 23 | Oct 26 | Oct 29 | Nov 1 | Nov 6 |
| 32°F | Oct 21 | Oct 27 | Oct 30 | Nov 1 | Nov 4 | Nov 7 | Nov 9 | Nov 12 | Nov 17 |
| 28°F | Nov 2 | Nov 6 | Nov 9 | Nov 12 | Nov 16 | Nov 19 | Nov 23 | Nov 28 | Dec 3 |
| 24°F | Nov 12 | Nov 17 | Nov 21 | Nov 25 | Nov 28 | Dec 1 | Dec 5 | Dec 9 | Dec 15 |
| 20°F | Nov 23 | Nov 29 | Dec 2 | Dec 6 | Dec 10 | Dec 13 | Dec 17 | Dec 22 | Dec 29 |
| 16°F | Dec 3 | Dec 10 | Dec 15 | Dec 18 | Dec 22 | Dec 26 | Dec 30 | Jan 2 | Jan 10 |
Freeze probabilities 1991–2020 at Erie International Airport, 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 16510 →Compare Erie with another place →
Weather by month in Erie
July is the warmest month at Erie International Airport, PA, averaging 81°F by day and 64°F at night; January is the coldest at 35°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 35% of years.
Warmth for growing adds up to 3,010 growing degree days a year (base 50°F), more than at 53% of the 176 Pennsylvania stations. 32% of them (955) have built up by the end of June, and July adds the most, 702. Precipitation totals 43.1 inches a year, most in October (4.4") and least in February (2.5"); May to September bring 42% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 35 | 21 | 3.4 | 100% | 26 | 3 |
| Feb | 37 | 21 | 2.5 | 100% | 24 | 4 |
| Mar | 44 | 28 | 3.1 | 100% | 22 | 21 |
| Apr | 57 | 38 | 3.5 | 99% | 8 | 86 |
| May | 68 | 49 | 3.5 | 35% | <1 | 293 |
| Jun | 77 | 59 | 3.7 | 0% | 0 | 548 |
| Jul | 81 | 64 | 3.3 | 0% | 0 | 702 |
| Aug | 80 | 63 | 3.4 | 0% | 0 | 668 |
| Sep | 74 | 57 | 4.3 | 0% | 0 | 457 |
| Oct | 62 | 46 | 4.4 | 34% | <1 | 180 |
| Nov | 51 | 37 | 3.8 | 99% | 9 | 43 |
| Dec | 40 | 28 | 4.2 | 100% | 22 | 6 |
Monthly normals 1991–2020 at Erie International Airport, PA (730 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, Union City Filtration Plant, PA, 17 miles southeast of Erie and 670 feet higher, has a last frost 11 days later (May 7), a first frost 25 days earlier (October 10), a season 37 days shorter.
When it snows in Erie, Pennsylvania
The first measurable snow (0.1 inch or more) in Erie usually arrives around November 11, and the last of the season around April 9. Those are the middle dates across the winters of 1991–2020 at Erie International Airport, PA, 9.9 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 17 days after the last snow.
Planting calendar for 16510
| 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 August 12 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 21 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| November 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 16510 is 10 miles from Erie International Airport, PA, which stands at 730 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 16 other ZIP codes share the station; its figures are presented in full for 16509 (Erie). The 2023 USDA Plant Hardiness Zone Map lists ZIP 16510 in zone 6b, the band where the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°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.