USDA Hardiness Zone 6a
Frost Dates for 48430 — Fenton, Michigan
NOAA 1991–2020 normals from Linden Wwtp, MI (863 ft), 4 miles northwest.
Updated
In Fenton, the last spring frost (32°F) is around May 3 in half of years and has passed by May 20 in nine years out of ten. The first fall frost comes around October 12, as early as September 30 one year in ten, leaving a typical freeze-free season of 161 days (NOAA, Linden Wwtp, MI).
- Last spring frost
- May 3
- First fall frost
- October 12
- Growing season
- 161 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 15
- Last snow
- April 13
- Winters with snow
- 100%
- Snow per year
- 52.1"
median, 1991–2020
median, 1991–2020
30 of 30 observed
NOAA normal
Frost risk by date in Fenton
Half of springs at Linden Wwtp, MI see their last 32°F night by May 3; only one in ten is past it by April 21, and one in ten still has one after May 20. Planting tender crops after May 10 leaves a 30% risk of a frost on them, after May 15 20%, and after May 20 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 12 in half of years, as early as September 30 one year in ten, and holds off past October 28 one year in ten. A hard freeze of 28°F follows 15 days later, around October 27; in spring the one-in-ten date for 28°F is May 9, 11 days before the 32°F one. The freeze-free season lasts 161 days in a typical year, longer than at 56% of the 172 Michigan stations; it reaches 181 days one year in ten and falls short of 141 one year in ten. On average 149 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 15, and return around October 1. Severe cold of 16°F or below comes every winter, usually between December 1 and March 21.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 30 | May 3 | May 7 | May 11 | May 15 | May 18 | May 22 | May 25 | May 30 |
| 32°F | Apr 21 | Apr 24 | Apr 28 | Apr 30 | May 3 | May 5 | May 10 | May 15 | May 20 |
| 28°F | Apr 10 | Apr 14 | Apr 17 | Apr 20 | Apr 23 | Apr 26 | Apr 29 | May 2 | May 9 |
| 24°F | Mar 31 | Apr 2 | Apr 5 | Apr 8 | Apr 11 | Apr 13 | Apr 16 | Apr 19 | Apr 23 |
| 20°F | Mar 16 | Mar 21 | Mar 25 | Mar 29 | Mar 31 | Apr 2 | Apr 4 | Apr 7 | Apr 14 |
| 16°F | Mar 7 | Mar 13 | Mar 16 | Mar 18 | Mar 21 | Mar 24 | Mar 27 | Mar 31 | Apr 3 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 20 | Sep 23 | Sep 26 | Sep 29 | Oct 1 | Oct 3 | Oct 5 | Oct 8 | Oct 13 |
| 32°F | Sep 30 | Oct 3 | Oct 7 | Oct 10 | Oct 12 | Oct 15 | Oct 19 | Oct 22 | Oct 28 |
| 28°F | Oct 10 | Oct 16 | Oct 20 | Oct 23 | Oct 27 | Oct 30 | Nov 1 | Nov 4 | Nov 9 |
| 24°F | Oct 24 | Oct 30 | Nov 1 | Nov 4 | Nov 7 | Nov 10 | Nov 13 | Nov 17 | Nov 24 |
| 20°F | Nov 5 | Nov 9 | Nov 14 | Nov 18 | Nov 21 | Nov 25 | Nov 28 | Dec 1 | Dec 7 |
| 16°F | Nov 15 | Nov 21 | Nov 25 | Nov 28 | Dec 1 | Dec 4 | Dec 8 | Dec 13 | Dec 19 |
Freeze probabilities 1991–2020 at Linden Wwtp, 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 48430 →Compare Fenton with another place →
Frost risk through the year in Fenton
In Fenton, the spring curve drops under 10% on May 20 and the fall curve passes 10% on September 30, 133 days later; that gap is longer than at 59% of the 172 Michigan stations with frost dates. The spring risk falls from 90% to 10% over 29 days (April 21 to May 20) and the fall risk climbs from 10% to 90% over 28 days (September 30 to October 28): both ends of the season vary about as much. At Flint Bishop International Airport, MI, 13 miles north, the same gap runs from May 23 to September 26, 7 days shorter.
| Planted on | Another 32°F night | 28°F night |
|---|---|---|
| Apr 19 | over 90% | 63% |
| Apr 26 | 75% | 40% |
| May 350% date | 50% | 19% |
| May 10 | 30% | under 10% |
| May 17 | 16% | under 10% |
| May 24 | under 10% | under 10% |
Weather by month in Fenton
July is the warmest month at Linden Wwtp, MI, averaging 81°F by day and 59°F at night; January is the coldest at 30°F and 15°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 58% of years.
Warmth for growing adds up to 2,422 growing degree days a year (base 50°F), fewer than at 53% of the 172 Michigan stations. 33% of them (791) have built up by the end of June, and July adds the most, 607.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 30 | 15 | 100% | 29 | 0 |
| Feb | 33 | 15 | 100% | 27 | 0 |
| Mar | 42 | 24 | 100% | 25 | 13 |
| Apr | 55 | 34 | 100% | 13 | 53 |
| May | 68 | 46 | 58% | 2 | 241 |
| Jun | 77 | 55 | 0% | 0 | 484 |
| Jul | 81 | 59 | 0% | 0 | 607 |
| Aug | 79 | 58 | 0% | 0 | 561 |
| Sep | 72 | 50 | 12% | 0 | 342 |
| Oct | 59 | 40 | 93% | 6 | 103 |
| Nov | 47 | 30 | 100% | 19 | 16 |
| Dec | 34 | 21 | 100% | 28 | 1 |
Monthly normals 1991–2020 at Linden Wwtp, MI (863 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, Flint Bishop International Airport, MI, 13 miles north of Fenton, has a last frost 3 days later (May 6), a first frost 2 days earlier (October 10), a season 6 days shorter.
When it snows in Fenton, Michigan
The first measurable snow (0.1 inch or more) in Fenton usually arrives around November 15, and the last of the season around April 13. Those are the middle dates across the winters of 1991–2020 at Flint Bishop International Airport, MI, 12.6 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 20 days after the last snow.
Planting calendar for 48430
| When | What to do |
|---|---|
| February 22 – March 8 | Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out. |
| March 8 – March 22 | Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early. |
| April 5 – April 19 | Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil. |
| May 3 onward | Transplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast. |
| by July 20 | Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops. |
| by September 28 | Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation. |
| October 12 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 48430 is 4 miles from Linden Wwtp, MI, which stands at 863 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 48430 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.