USDA Hardiness Zone 6b
Frost Dates for 14621 — Rochester, New York
NOAA 1991–2020 normals from Rochester Gtr International Airport, NY (533 ft), 6 miles southwest.
Updated
In Rochester, the last spring frost (32°F) is around April 24 in half of years and has passed by May 8 in nine years out of ten. The first fall frost comes around October 25, as early as October 8 one year in ten, leaving a typical freeze-free season of 181 days (NOAA, Rochester Gtr International Airport, NY).
- Last spring frost
- April 24
- First fall frost
- October 25
- Growing season
- 181 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 8
- Last snow
- April 11
- Winters with snow
- 100%
- Snow per year
- 102"
median, 1991–2020
median, 1991–2020
30 of 30 observed
NOAA normal
Frost risk by date in Rochester
Half of springs at Rochester Gtr International Airport, NY see their last 32°F night by April 24; only one in ten is past it by April 12, and one in ten still has one after May 8. Planting tender crops after April 30 leaves a 30% risk of a frost on them, after May 3 20%, and after May 8 10%. The 14 days between the even-odds date and the one-in-ten date is narrower than at 63% of the 173 New York stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 25 in half of years, as early as October 8 one year in ten, and holds off past November 7 one year in ten. A hard freeze of 28°F follows 12 days later, around November 6; in spring the one-in-ten date for 28°F is April 26, 12 days before the 32°F one. The freeze-free season lasts 181 days in a typical year, longer than at 75% of the 173 New York stations; it reaches 201 days one year in ten and falls short of 162 one year in ten. On average 129 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 4, and return around October 11. Severe cold of 16°F or below comes every winter, usually between December 8 and March 15.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 23 | Apr 27 | Apr 29 | May 1 | May 4 | May 7 | May 10 | May 14 | May 19 |
| 32°F | Apr 12 | Apr 16 | Apr 19 | Apr 22 | Apr 24 | Apr 27 | Apr 30 | May 3 | May 8 |
| 28°F | Apr 1 | Apr 4 | Apr 7 | Apr 10 | Apr 14 | Apr 16 | Apr 19 | Apr 22 | Apr 26 |
| 24°F | Mar 19 | Mar 24 | Mar 29 | Apr 1 | Apr 2 | Apr 4 | Apr 7 | Apr 11 | Apr 16 |
| 20°F | Mar 9 | Mar 14 | Mar 18 | Mar 21 | Mar 24 | Mar 28 | Mar 31 | Apr 1 | Apr 6 |
| 16°F | Feb 28 | Mar 5 | Mar 9 | Mar 12 | Mar 15 | Mar 18 | Mar 21 | Mar 25 | Mar 30 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 28 | Oct 1 | Oct 4 | Oct 7 | Oct 11 | Oct 14 | Oct 17 | Oct 20 | Oct 27 |
| 32°F | Oct 8 | Oct 14 | Oct 18 | Oct 22 | Oct 25 | Oct 28 | Oct 31 | Nov 3 | Nov 7 |
| 28°F | Oct 25 | Oct 30 | Nov 1 | Nov 3 | Nov 6 | Nov 8 | Nov 11 | Nov 15 | Nov 21 |
| 24°F | Nov 4 | Nov 8 | Nov 12 | Nov 15 | Nov 18 | Nov 21 | Nov 25 | Nov 29 | Dec 3 |
| 20°F | Nov 14 | Nov 19 | Nov 22 | Nov 26 | Nov 29 | Dec 1 | Dec 4 | Dec 9 | Dec 16 |
| 16°F | Nov 22 | Nov 28 | Dec 1 | Dec 4 | Dec 8 | Dec 12 | Dec 16 | Dec 21 | Dec 28 |
Freeze probabilities 1991–2020 at Rochester Gtr International Airport, 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 14621 →Compare Rochester with another place →
Weather by month in Rochester
July is the warmest month at Rochester Gtr International Airport, NY, averaging 83°F by day and 62°F at night; January is the coldest at 33°F and 19°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 2,835 growing degree days a year (base 50°F), more than at 77% of the 173 New York stations. 32% of them (913) have built up by the end of June, and July adds the most, 693. Precipitation totals 35.3 inches a year, most in July (3.6") and least in February (2.1"); May to September bring 46% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 33 | 19 | 2.6 | 100% | 27 | 2 |
| Feb | 35 | 20 | 2.1 | 100% | 25 | 2 |
| Mar | 44 | 27 | 2.5 | 100% | 23 | 15 |
| Apr | 57 | 37 | 3.0 | 99% | 10 | 75 |
| May | 69 | 48 | 2.9 | 26% | 1 | 290 |
| Jun | 78 | 57 | 3.4 | 0% | 0 | 530 |
| Jul | 83 | 62 | 3.6 | 0% | 0 | 693 |
| Aug | 81 | 61 | 3.3 | 0% | 0 | 643 |
| Sep | 74 | 54 | 3.2 | 1% | <1 | 411 |
| Oct | 61 | 43 | 3.2 | 70% | 3 | 143 |
| Nov | 49 | 34 | 2.8 | 100% | 15 | 29 |
| Dec | 39 | 25 | 2.7 | 100% | 25 | 3 |
Monthly normals 1991–2020 at Rochester Gtr International Airport, NY (533 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, Webster 2 NE, NY, 12 miles east of Rochester and 258 feet lower, has a last frost 7 days later (May 1), a first frost 5 days earlier (October 20), a season 10 days shorter.
When it snows in Rochester, New York
The first measurable snow (0.1 inch or more) in Rochester usually arrives around November 8, and the last of the season around April 11. Those are the middle dates across the winters of 1991–2020 at Rochester Gtr International Airport, NY, 6 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 13 days after the last snow.
Planting calendar for 14621
| When | What to do |
|---|---|
| February 13 – February 27 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| February 27 – March 13 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| March 27 – April 10 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 24 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by August 2 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 11 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 25 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 14621 is 6 miles from Rochester Gtr International Airport, NY, which stands at 533 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 25 other ZIP codes share the station; its figures are presented in full for 14609 (Rochester). The 2023 USDA Plant Hardiness Zone Map lists ZIP 14621 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.
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.