USDA Hardiness Zone 6b
Frost Dates for 43449 — Oak Harbor, Ohio
NOAA 1991–2020 normals from Fremont, OH (600 ft), 14 miles south.
Updated
In Oak Harbor, 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 October 23, as early as October 8 one year in ten, leaving a typical freeze-free season of 179 days (NOAA, Fremont, OH).
- Last spring frost
- April 26
- First fall frost
- October 23
- Growing season
- 179 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
- December 7
- Last snow
- March 21
- Winters with snow
- 100%
- Snow per year
- 26.2"
median, 1991–2020
median, 1991–2020
25 of 25 observed
NOAA normal
Frost risk by date in Oak Harbor
Half of springs at Fremont, OH see their last 32°F night by April 26; only one in ten is past it by April 11, 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 7 20%, and after May 13 10%. The 17 days between the even-odds date and the one-in-ten date is narrower than at 24% of the 148 Ohio 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 10 days later, around November 2; in spring the one-in-ten date for 28°F is April 30, 13 days before the 32°F one. The freeze-free season lasts 179 days in a typical year, shorter than at 51% of the 148 Ohio stations; it reaches 199 days one year in ten and falls short of 159 one year in ten. On average 126 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 6, and return around October 9. Severe cold of 16°F or below comes every winter, usually between December 7 and March 13.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 22 | Apr 26 | Apr 30 | May 2 | May 6 | May 9 | May 12 | May 17 | May 21 |
| 32°F | Apr 11 | Apr 15 | Apr 20 | Apr 23 | Apr 26 | Apr 30 | May 2 | May 7 | May 13 |
| 28°F | Mar 31 | Apr 3 | Apr 7 | Apr 10 | Apr 14 | Apr 17 | Apr 21 | Apr 25 | Apr 30 |
| 24°F | Mar 16 | Mar 22 | Mar 27 | Mar 30 | Apr 1 | Apr 3 | Apr 6 | Apr 11 | Apr 17 |
| 20°F | Mar 4 | Mar 11 | Mar 15 | Mar 18 | Mar 22 | Mar 25 | Mar 29 | Mar 31 | Apr 5 |
| 16°F | Feb 21 | Mar 1 | Mar 5 | Mar 9 | Mar 13 | Mar 15 | Mar 19 | Mar 23 | Mar 29 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 27 | Oct 1 | Oct 4 | Oct 6 | Oct 9 | Oct 12 | Oct 15 | Oct 18 | Oct 23 |
| 32°F | Oct 8 | Oct 13 | Oct 17 | Oct 20 | Oct 23 | Oct 26 | Oct 28 | Nov 1 | Nov 4 |
| 28°F | Oct 21 | Oct 26 | Oct 29 | Nov 1 | Nov 2 | Nov 5 | Nov 8 | Nov 13 | Nov 19 |
| 24°F | Nov 1 | Nov 5 | Nov 8 | Nov 12 | Nov 15 | Nov 19 | Nov 23 | Nov 26 | Dec 1 |
| 20°F | Nov 9 | Nov 14 | Nov 19 | Nov 23 | Nov 27 | Nov 30 | Dec 3 | Dec 8 | Dec 16 |
| 16°F | Nov 20 | Nov 26 | Nov 30 | Dec 3 | Dec 7 | Dec 11 | Dec 16 | Dec 21 | Dec 27 |
Freeze probabilities 1991–2020 at Fremont, OH, 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 43449 →Compare Oak Harbor with another place →
Weather by month in Oak Harbor
July is the warmest month at Fremont, OH, averaging 85°F by day and 63°F at night; January is the coldest at 34°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 36% of years.
Warmth for growing adds up to 3,170 growing degree days a year (base 50°F), fewer than at 59% of the 148 Ohio stations. 34% of them (1,080) have built up by the end of June, and July adds the most, 745. Precipitation totals 38.1 inches a year, most in June (4.1") and least in February (2.4"); 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 | 19 | 2.7 | 100% | 28 | 1 |
| Feb | 37 | 20 | 2.4 | 100% | 25 | 3 |
| Mar | 47 | 28 | 2.8 | 100% | 22 | 25 |
| Apr | 60 | 38 | 3.8 | 98% | 8 | 101 |
| May | 72 | 49 | 3.8 | 36% | 1 | 339 |
| Jun | 81 | 60 | 4.1 | 0% | 0 | 612 |
| Jul | 85 | 63 | 3.6 | 0% | 0 | 745 |
| Aug | 83 | 61 | 3.4 | 0% | 0 | 680 |
| Sep | 77 | 54 | 3.2 | 1% | 0 | 459 |
| Oct | 64 | 42 | 2.9 | 79% | 4 | 170 |
| Nov | 50 | 33 | 2.8 | 100% | 15 | 32 |
| Dec | 39 | 25 | 2.6 | 100% | 24 | 5 |
Monthly normals 1991–2020 at Fremont, OH (600 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, Fremont Ag Stn, OH, 15 miles south of Oak Harbor, has a last frost 5 days earlier (April 21), a first frost 1 day later (October 24), a season 4 days longer.
When it snows in Oak Harbor, Ohio
The first measurable snow (0.1 inch or more) in Oak Harbor usually arrives around December 7, and the last of the season around March 21. Those are the middle dates across the winters of 1991–2020 at Fremont, OH, 13.9 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 36 days after the last snow.
Planting calendar for 43449
| 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 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 43449 is 14 miles from Fremont, OH, which stands at 600 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 3 other ZIP codes share the station; its figures are presented in full for 43420 (Fremont). The 2023 USDA Plant Hardiness Zone Map lists ZIP 43449 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.