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USDA Hardiness Zone 6a

Frost Dates for 48428 — Dryden, Michigan

NOAA 1991–2020 normals from Lapeer Wwtp, MI (820 ft), 12 miles northwest.

Updated

In Dryden, the last spring frost (32°F) is around May 4 in half of years and has passed by May 22 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 160 days (NOAA, Lapeer Wwtp, MI).

Last spring frost
May 4

50% probability

First fall frost
October 14

50% probability

Growing season
160 days

freeze-free, 50%

Hardiness zone
6a

-10 to -5°F (-23.3 to -20.6°C) coldest night

First snow
November 29

median, 1991–2020

Last snow
March 30

median, 1991–2020

Winters with snow
100%

23 of 23 observed

Snow per year
34.4"

NOAA normal

Frost risk by date in Dryden

Half of springs at Lapeer Wwtp, MI see their last 32°F night by May 4; only one in ten is past it by April 22, and one in ten still has one after May 22. Planting tender crops after May 12 leaves a 30% risk of a frost on them, after May 16 20%, and after May 22 10%. The 18 days between the even-odds date and the one-in-ten date is wider than at 81% 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 28 one year in ten. A hard freeze of 28°F follows 14 days later, around October 28; in spring the one-in-ten date for 28°F is May 10, 12 days before the 32°F one. The freeze-free season lasts 160 days in a typical year, longer than at 51% of the 172 Michigan stations; it reaches 180 days one year in ten and falls short of 140 one year in ten. On average 148 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 17, and return around October 2. Severe cold of 16°F or below comes every winter, usually between December 1 and March 21.

Spring: the chance of another night this cold after the date
Low90%80%70%60%50%40%30%20%10%
36°FApr 30May 5May 10May 13May 17May 20May 24May 27May 31
32°FApr 22Apr 26Apr 30May 1May 4May 8May 12May 16May 22
28°FApr 8Apr 15Apr 19Apr 21Apr 24Apr 28Apr 30May 4May 10
24°FMar 28Apr 2Apr 4Apr 7Apr 11Apr 15Apr 18Apr 21Apr 26
20°FMar 17Mar 22Mar 27Mar 31Apr 1Apr 3Apr 6Apr 10Apr 16
16°FMar 7Mar 12Mar 15Mar 18Mar 21Mar 24Mar 29Mar 31Apr 4
Fall: the chance the first night this cold has come by the date
Low10%20%30%40%50%60%70%80%90%
36°FSep 20Sep 24Sep 28Sep 30Oct 2Oct 4Oct 7Oct 10Oct 14
32°FSep 29Oct 3Oct 7Oct 10Oct 14Oct 17Oct 20Oct 24Oct 28
28°FOct 12Oct 19Oct 22Oct 25Oct 28Oct 31Nov 2Nov 5Nov 10
24°FOct 27Nov 1Nov 2Nov 5Nov 8Nov 11Nov 15Nov 18Nov 23
20°FNov 3Nov 8Nov 12Nov 16Nov 19Nov 23Nov 27Dec 1Dec 5
16°FNov 12Nov 19Nov 23Nov 28Dec 1Dec 3Dec 7Dec 12Dec 19

Freeze probabilities 1991–2020 at Lapeer 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 48428 →Compare Dryden with another place →

Weather by month in Dryden

July is the warmest month at Lapeer Wwtp, MI, averaging 82°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 63% of years.

Warmth for growing adds up to 2,576 growing degree days a year (base 50°F), more than at 60% of the 172 Michigan stations. 32% of them (835) have built up by the end of June, and July adds the most, 648. Precipitation totals 31.9 inches a year, most in July (3.3") and least in February (1.9"); May to September bring 49% of it.

Monthly normals 1991–2020 at Lapeer Wwtp, MI
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan30152.3100%290
Feb33151.9100%260
Mar43231.9100%2514
Apr56343.1100%1558
May69453.263%2255
Jun79553.10%0508
Jul82593.30%0648
Aug81583.10%0592
Sep74502.813%<1367
Oct61402.993%6116
Nov47302.4100%1916
Dec36221.9100%272

Monthly normals 1991–2020 at Lapeer Wwtp, MI (820 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, Lapeer 2W, MI, 14 miles northwest of Dryden, has the same 50% last-frost date, a first frost 1 day earlier (October 13), a season 1 day longer.

Frost dates for 48421 (Columbiaville) →

When it snows in Dryden, Michigan

The first measurable snow (0.1 inch or more) in Dryden usually arrives around November 29, and the last of the season around March 30. Those are the middle dates across the winters of 1991–2020 at Lapeer Wwtp, MI, 12.3 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 35 days after the last snow.

Planting calendar for 48428

What to do and when, from the 50% frost dates for Dryden, Michigan
WhenWhat to do
February 23 – March 9Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
March 9 – March 23Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
April 6 – April 20Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
May 4 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by July 22Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by September 30Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 14 onwardPlant 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 48428 is 12 miles from Lapeer Wwtp, MI, which stands at 820 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 5 other ZIP codes share the station; its figures are presented in full for 48446 (Lapeer). The 2023 USDA Plant Hardiness Zone Map lists ZIP 48428 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.

Frost dates across Michigan →

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.

ZIP codes measured at the same station

Other zone 6a places in Michigan