USDA Hardiness Zone 6a
Frost Dates for 48634 — Linwood, Michigan
NOAA 1991–2020 normals from Auburn 2NE, MI (605 ft), 9 miles south.
Updated
In Linwood, the last spring frost (32°F) is around May 3 in half of years and has passed by May 23 in nine years out of ten. The first fall frost comes around October 14, as early as September 29 one year in ten, leaving a typical freeze-free season of 161 days (NOAA, Auburn 2NE, MI).
- Last spring frost
- May 3
- First fall frost
- October 14
- 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 25
- Last snow
- March 19
- Winters with snow
- 100%
- Snow per year
- —
median, 1991–2020
median, 1991–2020
15 of 15 observed
NOAA normal
Frost risk by date in Linwood
Half of springs at Auburn 2NE, MI see their last 32°F night by May 3; only one in ten is past it by April 20, and one in ten still has one after May 23. Planting tender crops after May 12 leaves a 30% risk of a frost on them, after May 17 20%, and after May 23 10%. The 20 days between the even-odds date and the one-in-ten date is wider than at 95% 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 September 29 one year in ten, and holds off past October 30 one year in ten. A hard freeze of 28°F follows 15 days later, around October 29; in spring the one-in-ten date for 28°F is May 10, 13 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 183 days one year in ten and falls short of 138 one year in ten. On average 158 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 13 days longer, to about May 16, and return around September 30. Severe cold of 16°F or below comes every winter, usually between November 30 and March 19.
| Low | 90% | 80% | 70% | 60% | 50% | 40% | 30% | 20% | 10% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 30 | May 4 | May 9 | May 13 | May 16 | May 20 | May 24 | May 27 | May 31 |
| 32°F | Apr 20 | Apr 24 | Apr 29 | May 1 | May 3 | May 7 | May 12 | May 17 | May 23 |
| 28°F | Apr 8 | Apr 13 | Apr 17 | Apr 20 | Apr 23 | Apr 27 | Apr 30 | May 4 | May 10 |
| 24°F | Mar 28 | Apr 2 | Apr 4 | Apr 7 | Apr 10 | Apr 14 | Apr 17 | Apr 20 | Apr 26 |
| 20°F | Mar 13 | Mar 19 | Mar 22 | Mar 26 | Mar 30 | Apr 1 | Apr 3 | Apr 5 | Apr 10 |
| 16°F | Mar 5 | Mar 9 | Mar 13 | Mar 16 | Mar 19 | Mar 21 | Mar 26 | Mar 29 | Apr 1 |
| Low | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 16 | Sep 21 | Sep 25 | Sep 28 | Sep 30 | Oct 2 | Oct 5 | Oct 9 | Oct 14 |
| 32°F | Sep 29 | Oct 2 | Oct 7 | Oct 10 | Oct 14 | Oct 18 | Oct 21 | Oct 24 | Oct 30 |
| 28°F | Oct 12 | Oct 19 | Oct 23 | Oct 26 | Oct 29 | Nov 1 | Nov 3 | Nov 6 | Nov 10 |
| 24°F | Oct 28 | Nov 1 | Nov 4 | Nov 6 | Nov 9 | Nov 12 | Nov 15 | Nov 18 | Nov 23 |
| 20°F | Nov 6 | Nov 11 | Nov 14 | Nov 17 | Nov 20 | Nov 23 | Nov 26 | Nov 30 | Dec 5 |
| 16°F | Nov 15 | Nov 20 | Nov 24 | Nov 27 | Nov 30 | Dec 2 | Dec 6 | Dec 12 | Dec 19 |
Freeze probabilities 1991–2020 at Auburn 2NE, 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 48634 →Compare Linwood with another place →
Weather by month in Linwood
July is the warmest month at Auburn 2NE, MI, averaging 83°F by day and 58°F at night; January is the coldest at 30°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 August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 60% of years.
Warmth for growing adds up to 2,476 growing degree days a year (base 50°F), more than at 51% of the 172 Michigan stations. 32% of them (785) have built up by the end of June, and July adds the most, 643.
| Month | High °F | Low °F | 32°F night | Nights ≤ 32°F | GDD 50°F |
|---|---|---|---|---|---|
| Jan | 30 | 14 | 100% | 30 | 0 |
| Feb | 33 | 15 | 100% | 27 | 1 |
| Mar | 42 | 24 | 100% | 27 | 10 |
| Apr | 56 | 34 | 100% | 16 | 48 |
| May | 68 | 45 | 60% | 2 | 229 |
| Jun | 78 | 55 | 0% | 0 | 498 |
| Jul | 83 | 58 | 0% | 0 | 643 |
| Aug | 81 | 56 | 0% | 0 | 569 |
| Sep | 74 | 49 | 14% | <1 | 351 |
| Oct | 61 | 40 | 91% | 8 | 114 |
| Nov | 48 | 30 | 100% | 20 | 14 |
| Dec | 35 | 21 | 100% | 29 | 0 |
Monthly normals 1991–2020 at Auburn 2NE, MI (605 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, Essexville, MI, 12 miles southeast of Linwood, has a last frost 6 days earlier (April 27), a first frost 6 days later (October 20), a season 12 days longer.
When it snows in Linwood, Michigan
The first measurable snow (0.1 inch or more) in Linwood usually arrives around November 25, and the last of the season around March 19. Those are the middle dates across the winters of 1991–2020 at Essexville, MI, 12.4 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 45 days after the last snow.
Planting calendar for 48634
| 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 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 48634 is 9 miles from Auburn 2NE, MI, which stands at 605 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 48611 (Auburn). The 2023 USDA Plant Hardiness Zone Map lists ZIP 48634 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.