USDA Hardiness Zone 6a
Frost Dates for 48169 — Pinckney, Michigan
NOAA 1991–2020 normals from Hell, MI (890 ft), 3 miles southwest.
Updated
In Pinckney, the last spring frost (32°F) is around April 30 in half of years and has passed by May 17 in nine years out of ten. The first fall frost comes around October 14, as early as October 1 one year in ten, leaving a typical freeze-free season of 166 days (NOAA, Hell, MI).
- Last spring frost
- April 30
- First fall frost
- October 14
- Growing season
- 166 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 25
- Last snow
- April 4
- Winters with snow
- 100%
- Snow per year
- 33.2"
median, 1991–2020
median, 1991–2020
22 of 22 observed
NOAA normal
Frost risk by date in Pinckney
Half of springs at Hell, MI see their last 32°F night by April 30; only one in ten is past it by April 16, and one in ten still has one after May 17. Planting tender crops after May 5 leaves a 30% risk of a frost on them, after May 10 20%, and after May 17 10%. The 17 days between the even-odds date and the one-in-ten date is wider than at 62% of the 172 Michigan stations behind this site's ZIP pages.
In fall the first 32°F night comes by October 14 in half of years, as early as October 1 one year in ten, and holds off past October 30 one year in ten. A hard freeze of 28°F follows 12 days later, around October 26; in spring the one-in-ten date for 28°F is May 4, 13 days before the 32°F one. The freeze-free season lasts 166 days in a typical year, longer than at 72% of the 172 Michigan stations; it reaches 187 days one year in ten and falls short of 145 one year in ten. On average 147 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 9, and return around October 3. Severe cold of 16°F or below comes every winter, usually between December 3 and March 21.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 26 | Apr 30 | May 3 | May 6 | May 9 | May 14 | May 18 | May 22 | May 26 |
| 32°F | Apr 16 | Apr 20 | Apr 24 | Apr 27 | Apr 30 | May 1 | May 5 | May 10 | May 17 |
| 28°F | Apr 5 | Apr 10 | Apr 13 | Apr 16 | Apr 18 | Apr 22 | Apr 25 | Apr 29 | May 4 |
| 24°F | Mar 26 | Mar 31 | Apr 2 | Apr 4 | Apr 7 | Apr 9 | Apr 13 | Apr 16 | Apr 21 |
| 20°F | Mar 15 | Mar 21 | Mar 24 | Mar 28 | Mar 30 | Apr 1 | Apr 3 | Apr 5 | Apr 11 |
| 16°F | Mar 6 | Mar 11 | Mar 16 | Mar 18 | Mar 21 | Mar 24 | Mar 27 | Mar 30 | Apr 2 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 22 | Sep 26 | Sep 29 | Oct 1 | Oct 3 | Oct 5 | Oct 8 | Oct 12 | Oct 17 |
| 32°F | Oct 1 | Oct 5 | Oct 8 | Oct 11 | Oct 14 | Oct 17 | Oct 20 | Oct 24 | Oct 30 |
| 28°F | Oct 10 | Oct 16 | Oct 20 | Oct 23 | Oct 26 | Oct 30 | Nov 1 | Nov 6 | Nov 12 |
| 24°F | Oct 22 | Oct 28 | Nov 1 | Nov 4 | Nov 7 | Nov 11 | Nov 15 | Nov 19 | Nov 26 |
| 20°F | Nov 4 | Nov 10 | Nov 13 | Nov 18 | Nov 22 | Nov 25 | Nov 29 | Dec 3 | Dec 9 |
| 16°F | Nov 14 | Nov 21 | Nov 25 | Nov 30 | Dec 3 | Dec 7 | Dec 11 | Dec 16 | Dec 22 |
Freeze probabilities 1991–2020 at Hell, MI, 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 48169 →Compare Pinckney with another place →
Frost risk through the year in Pinckney
In Pinckney, the spring curve drops under 10% on May 17 and the fall curve passes 10% on October 1, 137 days later; that gap is longer than at 70% of the 172 Michigan stations with frost dates. The spring risk falls from 90% to 10% over 31 days (April 16 to May 17) and the fall risk climbs from 10% to 90% over 29 days (October 1 to October 30): both ends of the season vary about as much. At Whitmore Lake 1NW, MI, 8 miles east, the same gap runs from May 21 to September 30, 5 days shorter.
| Planted on | Another 32°F night | 28°F night |
|---|---|---|
| Apr 16 | over 90% | 60% |
| Apr 23 | 73% | 37% |
| Apr 3050% date | 50% | 18% |
| May 7 | 26% | under 10% |
| May 14 | 14% | under 10% |
| May 21 | under 10% | under 10% |
Weather by month in Pinckney
July is the warmest month at Hell, MI, averaging 81°F by day and 59°F at night; January is the coldest at 32°F and 14°F. A freezing night is all but certain in every month from October 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 44% of years.
Warmth for growing adds up to 2,614 growing degree days a year (base 50°F), more than at 64% of the 172 Michigan stations. 34% of them (892) have built up by the end of June, and July adds the most, 625.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 32 | 14 | 100% | 28 | 1 |
| Feb | 35 | 16 | 100% | 26 | 1 |
| Mar | 44 | 24 | 100% | 24 | 15 |
| Apr | 58 | 35 | 100% | 11 | 71 |
| May | 70 | 47 | 44% | 2 | 287 |
| Jun | 78 | 56 | 0% | 0 | 518 |
| Jul | 81 | 59 | 0% | 0 | 625 |
| Aug | 81 | 58 | 0% | 0 | 603 |
| Sep | 74 | 50 | 7% | 0 | 372 |
| Oct | 61 | 39 | 90% | 9 | 108 |
| Nov | 48 | 31 | 100% | 19 | 13 |
| Dec | 36 | 22 | 100% | 27 | 2 |
Monthly normals 1991–2020 at Hell, MI (890 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, Whitmore Lake 1NW, MI, 8 miles east of Pinckney, has a last frost 5 days later (May 5), a first frost 1 day earlier (October 13), a season 6 days shorter.
When it snows in Pinckney, Michigan
The first measurable snow (0.1 inch or more) in Pinckney usually arrives around November 25, and the last of the season around April 4. Those are the middle dates across the winters of 1991–2020 at Howell Wwtp, MI, 9.6 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 26 days after the last snow.
Planting calendar for 48169
| When | What to do |
|---|---|
| February 19 – March 5 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 5 – March 19 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| April 2 – April 16 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| April 30 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 22 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by September 30 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 14 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 48169 is 3 miles from Hell, MI, which stands at 890 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 48169 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.