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USDA Hardiness Zone 5a

Frost Dates for 54486 — Tigerton, Wisconsin

NOAA 1991–2020 normals from Rosholt 9 NNE, WI (1,183 ft), 10 miles west.

Updated

In Tigerton, the last spring frost (32°F) is around May 6 in half of years and has passed by May 21 in nine years out of ten. The first fall frost comes around October 5, as early as September 22 one year in ten, leaving a typical freeze-free season of 150 days (NOAA, Rosholt 9 NNE, WI).

Last spring frost
May 6

50% probability

First fall frost
October 5

50% probability

Growing season
150 days

freeze-free, 50%

Hardiness zone
5a

-20 to -15°F (-28.9 to -26.1°C) coldest night

First snow
November 6

median, 1991–2020

Last snow
April 12

median, 1991–2020

Winters with snow
100%

27 of 27 observed

Snow per year
—

NOAA normal

Frost risk by date in Tigerton

Half of springs at Rosholt 9 NNE, WI see their last 32°F night by May 6; only one in ten is past it by April 24, and one in ten still has one after May 21. Planting tender crops after May 12 leaves a 30% risk of a frost on them, after May 16 20%, and after May 21 10%. The 15 days between the even-odds date and the one-in-ten date is narrower than at 30% of the 182 Wisconsin stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 5 in half of years, as early as September 22 one year in ten, and holds off past October 20 one year in ten. A hard freeze of 28°F follows 12 days later, around October 17; in spring the one-in-ten date for 28°F is May 10, 11 days before the 32°F one. The freeze-free season lasts 150 days in a typical year, shorter than at 64% of the 182 Wisconsin stations; it reaches 169 days one year in ten and falls short of 130 one year in ten. On average 178 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 19, and return around September 26. Severe cold of 16°F or below comes every winter, usually between November 18 and March 29.

Spring: the chance of another night this cold after the date
Low90%80%70%60%50%40%30%20%10%
36°FMay 5May 9May 13May 16May 19May 22May 25May 29Jun 2
32°FApr 24Apr 28Apr 30May 3May 6May 9May 12May 16May 21
28°FApr 11Apr 16Apr 20Apr 23Apr 26Apr 29May 1May 4May 10
24°FMar 31Apr 4Apr 7Apr 10Apr 13Apr 17Apr 20Apr 24Apr 29
20°FMar 19Mar 26Mar 30Apr 1Apr 3Apr 6Apr 9Apr 13Apr 19
16°FMar 12Mar 17Mar 21Mar 25Mar 29Mar 31Apr 2Apr 4Apr 9
Fall: the chance the first night this cold has come by the date
Low10%20%30%40%50%60%70%80%90%
36°FSep 12Sep 17Sep 20Sep 23Sep 26Sep 29Oct 1Oct 4Oct 8
32°FSep 22Sep 27Sep 30Oct 2Oct 5Oct 8Oct 11Oct 15Oct 20
28°FOct 1Oct 6Oct 10Oct 13Oct 17Oct 20Oct 24Oct 29Nov 2
24°FOct 14Oct 20Oct 25Oct 28Oct 31Nov 2Nov 4Nov 8Nov 13
20°FOct 28Nov 1Nov 4Nov 7Nov 10Nov 13Nov 16Nov 20Nov 24
16°FNov 3Nov 9Nov 13Nov 16Nov 18Nov 21Nov 23Nov 26Dec 1

Freeze probabilities 1991–2020 at Rosholt 9 NNE, WI, 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 54486 →Compare Tigerton with another place →

Weather by month in Tigerton

July is the warmest month at Rosholt 9 NNE, WI, averaging 81°F by day and 58°F at night; January is the coldest at 24°F and 7°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 70% of years.

Warmth for growing adds up to 2,320 growing degree days a year (base 50°F), fewer than at 63% of the 182 Wisconsin stations. 32% of them (751) have built up by the end of June, and July adds the most, 608. Precipitation totals 34.0 inches a year, most in June (4.5") and least in February (1.1"); May to September bring 59% of it.

Monthly normals 1991–2020 at Rosholt 9 NNE, WI
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan2471.2100%310
Feb2891.1100%280
Mar40211.7100%277
Apr54333.2100%1844
May67454.070%4231
Jun77554.50%0469
Jul81583.80%0608
Aug79574.00%0555
Sep71493.832%2320
Oct57373.098%1379
Nov42262.1100%257
Dec29151.6100%300

Monthly normals 1991–2020 at Rosholt 9 NNE, WI (1,183 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, Stockbridge-Munsee Rsvn, WI, 12 miles northeast of Tigerton, has a last frost 7 days later (May 13), a first frost 5 days earlier (September 30), a season 9 days shorter.

Frost dates for 54414 (Birnamwood) →

When it snows in Tigerton, Wisconsin

The first measurable snow (0.1 inch or more) in Tigerton usually arrives around November 6, and the last of the season around April 12. Those are the middle dates across the winters of 1991–2020 at Rosholt 9 NNE, WI, 9.9 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 24 days after the last snow.

Planting calendar for 54486

What to do and when, from the 50% frost dates for Tigerton, Wisconsin
WhenWhat to do
February 25 – March 11Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
March 11 – March 25Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
April 8 – April 22Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
May 6 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by July 13Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by September 21Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 5 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 54486 is 10 miles from Rosholt 9 NNE, WI, which stands at 1,183 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 4 other ZIP codes share the station; its figures are presented in full for 54945 (Iola). The 2023 USDA Plant Hardiness Zone Map lists ZIP 54486 in zone 5a, the band where the coldest night of the year averaged -20 to -15°F (-28.9 to -26.1°C) over 1991–2020; a zone describes winter lows, not frost dates.

Frost dates across Wisconsin →

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 5a places in Wisconsin