USDA Hardiness Zone 5b
Frost Dates for 13820 — Oneonta, New York
NOAA 1991–2020 normals from Emmons, NY (1,225 ft), 2 miles east.
Updated
In Oneonta, the last spring frost (32°F) is around May 17 in half of years and has passed by May 30 in nine years out of ten. The first fall frost comes around October 3, as early as September 20 one year in ten, leaving a typical freeze-free season of 141 days (NOAA, Emmons, NY).
- Last spring frost
- May 17
- First fall frost
- October 3
- Growing season
- 141 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 4
- Last snow
- April 9
- Winters with snow
- 100%
- Snow per year
- 83"
median, 1991–2020
median, 1991–2020
30 of 30 observed
NOAA normal
Frost risk by date in Oneonta
Half of springs at Emmons, NY see their last 32°F night by May 17; only one in ten is past it by April 30, and one in ten still has one after May 30. Planting tender crops after May 23 leaves a 30% risk of a frost on them, after May 26 20%, and after May 30 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 83% of the 173 New York stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 3 in half of years, as early as September 20 one year in ten, and holds off past October 18 one year in ten. A hard freeze of 28°F follows 13 days later, around October 16; in spring the one-in-ten date for 28°F is May 19, 11 days before the 32°F one. The freeze-free season lasts 141 days in a typical year, shorter than at 90% of the 173 New York stations; it reaches 161 days one year in ten and falls short of 121 one year in ten. On average 167 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 12 days longer, to about May 29, and return around September 22. Severe cold of 16°F or below comes every winter, usually between November 21 and April 1.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 14 | May 19 | May 23 | May 26 | May 29 | May 31 | Jun 2 | Jun 6 | Jun 10 |
| 32°F | Apr 30 | May 6 | May 10 | May 13 | May 17 | May 19 | May 23 | May 26 | May 30 |
| 28°F | Apr 21 | Apr 25 | Apr 28 | May 1 | May 4 | May 7 | May 10 | May 14 | May 19 |
| 24°F | Apr 7 | Apr 12 | Apr 16 | Apr 19 | Apr 22 | Apr 25 | Apr 28 | May 2 | May 8 |
| 20°F | Mar 29 | Apr 1 | Apr 3 | Apr 6 | Apr 7 | Apr 10 | Apr 13 | Apr 17 | Apr 21 |
| 16°F | Mar 18 | Mar 22 | Mar 26 | Mar 30 | Apr 1 | Apr 2 | Apr 4 | Apr 7 | Apr 11 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 10 | Sep 13 | Sep 17 | Sep 20 | Sep 22 | Sep 25 | Sep 28 | Sep 30 | Oct 3 |
| 32°F | Sep 20 | Sep 24 | Sep 28 | Oct 1 | Oct 3 | Oct 5 | Oct 7 | Oct 12 | Oct 18 |
| 28°F | Oct 1 | Oct 4 | Oct 8 | Oct 12 | Oct 16 | Oct 20 | Oct 25 | Oct 31 | Nov 3 |
| 24°F | Oct 10 | Oct 17 | Oct 23 | Oct 28 | Nov 1 | Nov 3 | Nov 5 | Nov 9 | Nov 14 |
| 20°F | Oct 28 | Nov 1 | Nov 5 | Nov 8 | Nov 11 | Nov 13 | Nov 16 | Nov 20 | Nov 26 |
| 16°F | Nov 6 | Nov 10 | Nov 14 | Nov 17 | Nov 21 | Nov 24 | Nov 27 | Dec 1 | Dec 6 |
Freeze probabilities 1991–2020 at Emmons, NY, 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 13820 →Compare Oneonta with another place →
Weather by month in Oneonta
July is the warmest month at Emmons, NY, averaging 78°F by day and 55°F at night; January is the coldest at 30°F and 11°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 87% of years.
Warmth for growing adds up to 1,963 growing degree days a year (base 50°F), fewer than at 95% of the 173 New York stations. 31% of them (600) have built up by the end of June, and July adds the most, 521. Precipitation totals 45.0 inches a year, most in June (4.7") and least in February (2.8"); May to September bring 46% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 30 | 11 | 3.3 | 100% | 29 | 1 |
| Feb | 32 | 12 | 2.8 | 100% | 27 | 0 |
| Mar | 41 | 19 | 3.5 | 100% | 27 | 5 |
| Apr | 55 | 30 | 3.9 | 100% | 19 | 40 |
| May | 67 | 41 | 3.7 | 87% | 5 | 180 |
| Jun | 74 | 51 | 4.7 | 7% | <1 | 375 |
| Jul | 78 | 55 | 4.5 | 0% | 0 | 521 |
| Aug | 77 | 54 | 4.0 | 0% | 0 | 482 |
| Sep | 70 | 47 | 3.8 | 38% | 1 | 274 |
| Oct | 58 | 37 | 3.9 | 98% | 10 | 74 |
| Nov | 46 | 28 | 3.3 | 100% | 21 | 11 |
| Dec | 35 | 19 | 3.6 | 100% | 28 | 1 |
Monthly normals 1991–2020 at Emmons, NY (1,225 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, E Sidney, NY, 13 miles southwest of Oneonta, has a last frost 6 days earlier (May 11), a first frost 6 days later (October 9), a season 10 days longer.
When it snows in Oneonta, New York
The first measurable snow (0.1 inch or more) in Oneonta usually arrives around November 4, and the last of the season around April 9. Those are the middle dates across the winters of 1991–2020 at Emmons, NY, 2.1 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 38 days after the last snow.
Planting calendar for 13820
| When | What to do |
|---|---|
| March 8 – March 22 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 22 – April 5 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| April 19 – May 3 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| May 17 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 11 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by September 19 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 3 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 13820 is 2 miles from Emmons, NY, which stands at 1,225 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. The 2023 USDA Plant Hardiness Zone Map lists ZIP 13820 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.
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.