USDA Hardiness Zone 6a
Frost Dates for 45801 — Lima, Ohio
NOAA 1991–2020 normals from Lima Wwtp, OH (850 ft), 3 miles southwest.
Updated
In Lima, the last spring frost (32°F) is around April 24 in half of years and has passed by May 11 in nine years out of ten. The first fall frost comes around October 24, as early as October 10 one year in ten, leaving a typical freeze-free season of 182 days (NOAA, Lima Wwtp, OH).
- Last spring frost
- April 24
- First fall frost
- October 24
- Growing season
- 182 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 23
- Last snow
- March 27
- Winters with snow
- 100%
- Snow per year
- 32.5"
median, 1991–2020
median, 1991–2020
30 of 30 observed
NOAA normal
Frost risk by date in Lima
Half of springs at Lima Wwtp, OH 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 11. Planting tender crops after April 30 leaves a 30% risk of a frost on them, after May 4 20%, and after May 11 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 24 in half of years, as early as October 10 one year in ten, and holds off past November 5 one year in ten. A hard freeze of 28°F follows 10 days later, around November 3; in spring the one-in-ten date for 28°F is April 29, 12 days before the 32°F one. The freeze-free season lasts 182 days in a typical year, longer than at 55% of the 148 Ohio stations; it reaches 199 days one year in ten and falls short of 161 one year in ten. On average 121 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 9 days longer, to about May 3, and return around October 13. Severe cold of 16°F or below comes every winter, usually between December 6 and March 12.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 21 | Apr 25 | Apr 29 | May 1 | May 3 | May 6 | May 9 | May 13 | May 20 |
| 32°F | Apr 12 | Apr 16 | Apr 19 | Apr 21 | Apr 24 | Apr 28 | Apr 30 | May 4 | May 11 |
| 28°F | Mar 31 | Apr 4 | Apr 8 | Apr 11 | Apr 14 | Apr 17 | Apr 20 | Apr 23 | Apr 29 |
| 24°F | Mar 18 | Mar 22 | Mar 28 | Mar 31 | Apr 1 | Apr 4 | Apr 7 | Apr 12 | Apr 16 |
| 20°F | Mar 4 | Mar 11 | Mar 16 | Mar 19 | Mar 22 | Mar 27 | Mar 30 | Apr 1 | Apr 6 |
| 16°F | Feb 21 | Mar 1 | Mar 4 | Mar 8 | Mar 12 | Mar 15 | Mar 19 | Mar 24 | Mar 29 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 28 | Oct 3 | Oct 7 | Oct 10 | Oct 13 | Oct 15 | Oct 19 | Oct 21 | Oct 26 |
| 32°F | Oct 10 | Oct 15 | Oct 19 | Oct 21 | Oct 24 | Oct 26 | Oct 29 | Nov 1 | Nov 5 |
| 28°F | Oct 22 | Oct 27 | Oct 30 | Nov 1 | Nov 3 | Nov 5 | Nov 9 | Nov 12 | Nov 18 |
| 24°F | Nov 1 | Nov 5 | Nov 8 | Nov 11 | Nov 15 | Nov 18 | Nov 22 | Nov 27 | Dec 2 |
| 20°F | Nov 9 | Nov 14 | Nov 18 | Nov 23 | Nov 27 | Dec 1 | Dec 3 | Dec 8 | Dec 15 |
| 16°F | Nov 18 | Nov 25 | Nov 29 | Dec 2 | Dec 6 | Dec 10 | Dec 15 | Dec 20 | Dec 26 |
Freeze probabilities 1991–2020 at Lima Wwtp, 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 45801 →Compare Lima with another place →
Weather by month in Lima
July is the warmest month at Lima Wwtp, OH, averaging 84°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 29% of years.
Warmth for growing adds up to 3,203 growing degree days a year (base 50°F), fewer than at 53% of the 148 Ohio stations. 34% of them (1,101) have built up by the end of June, and July adds the most, 725. Precipitation totals 41.1 inches a year, most in May (4.4") and least in February (2.5"); May to September bring 49% of it.
| Month | High °F | Low °F | Precip. in | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|---|
| Jan | 34 | 19 | 2.8 | 100% | 27 | 2 |
| Feb | 37 | 21 | 2.5 | 100% | 24 | 4 |
| Mar | 48 | 29 | 3.0 | 100% | 21 | 29 |
| Apr | 61 | 39 | 4.0 | 99% | 7 | 116 |
| May | 72 | 50 | 4.4 | 29% | 1 | 347 |
| Jun | 80 | 60 | 4.3 | 0% | 0 | 603 |
| Jul | 84 | 63 | 4.4 | 0% | 0 | 725 |
| Aug | 82 | 62 | 3.8 | 0% | 0 | 679 |
| Sep | 77 | 55 | 3.2 | 2% | 0 | 471 |
| Oct | 64 | 44 | 2.9 | 77% | 3 | 186 |
| Nov | 50 | 33 | 3.1 | 100% | 15 | 36 |
| Dec | 39 | 25 | 2.7 | 100% | 25 | 4 |
Monthly normals 1991–2020 at Lima Wwtp, OH (850 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, Lima Allen Co Airport, OH, 5 miles southeast of Lima, has a last frost 2 days earlier (April 22), a first frost 2 days earlier (October 22), a season 1 day shorter.
When it snows in Lima, Ohio
The first measurable snow (0.1 inch or more) in Lima usually arrives around November 23, and the last of the season around March 27. Those are the middle dates across the winters of 1991–2020 at Pandora, OH, 14.4 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 28 days after the last snow.
Planting calendar for 45801
| 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 1 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by October 10 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 24 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 45801 is 3 miles from Lima Wwtp, OH, which stands at 850 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 7 other ZIP codes share the station; its figures are presented in full for 45805 (Lima). The 2023 USDA Plant Hardiness Zone Map lists ZIP 45801 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.
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.