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USDA Hardiness Zone 5b

Frost Dates for 53128 — Genoa City, Wisconsin

NOAA 1991–2020 normals from Pell Lake, WI (840 ft), under a mile north.

Updated

In Genoa City, the last spring frost (32°F) is around April 30 in half of years and has passed by May 16 in nine years out of ten. The first fall frost comes around October 13, as early as September 28 one year in ten, leaving a typical freeze-free season of 164 days (NOAA, Pell Lake, WI).

Last spring frost
April 30

50% probability

First fall frost
October 13

50% probability

Growing season
164 days

freeze-free, 50%

Hardiness zone
5b

-15 to -10°F (-26.1 to -23.3°C) coldest night

First snow
November 9

median, 1991–2020

Last snow
April 12

median, 1991–2020

Winters with snow
100%

16 of 16 observed

Snow per year
40.1"

NOAA normal

Frost risk by date in Genoa City

Half of springs at Pell Lake, WI 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 16. Planting tender crops after May 6 leaves a 30% risk of a frost on them, after May 11 20%, and after May 16 10%. The 16 days between the even-odds date and the one-in-ten date is wider than at 70% of the 182 Wisconsin stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 13 in half of years, as early as September 28 one year in ten, and holds off past October 27 one year in ten. A hard freeze of 28°F follows 12 days later, around October 25; in spring the one-in-ten date for 28°F is May 4, 12 days before the 32°F one. The freeze-free season lasts 164 days in a typical year, longer than at 71% of the 182 Wisconsin stations; it reaches 185 days one year in ten and falls short of 144 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 12, and return around October 3. Severe cold of 16°F or below comes every winter, usually between November 27 and March 15.

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

Freeze probabilities 1991–2020 at Pell Lake, 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 53128 →Compare Genoa City with another place →

Weather by month in Genoa City

July is the warmest month at Pell Lake, WI, averaging 82°F by day and 59°F at night; January is the coldest at 29°F and 13°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 49% of years.

Warmth for growing adds up to 2,533 growing degree days a year (base 50°F), more than at 63% of the 182 Wisconsin stations. 33% of them (838) have built up by the end of June, and July adds the most, 637. Precipitation totals 36.5 inches a year, most in June (4.7") and least in February (1.5"); May to September bring 57% of it.

Monthly normals 1991–2020 at Pell Lake, WI
MonthHigh °FLow °FPrecip. in32°F nightNights ≤ 32°FGDD 50°F
Jan29131.7100%300
Feb33141.5100%270
Mar44252.2100%2319
Apr57353.4100%1258
May69464.349%2254
Jun78564.70%0507
Jul82594.40%0637
Aug80573.90%0575
Sep73503.614%<1356
Oct61392.995%9112
Nov46292.3100%2114
Dec35201.6100%271

Monthly normals 1991–2020 at Pell Lake, WI (840 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, Lake Geneva Wwtp, WI, 7 miles northwest of Genoa City, has a last frost 5 days earlier (April 25), a first frost 8 days later (October 21), a season 15 days longer.

Frost dates for 53147 (Lake Geneva) →

When it snows in Genoa City, Wisconsin

The first measurable snow (0.1 inch or more) in Genoa City usually arrives around November 9, and the last of the season around April 12. Those are the middle dates across the winters of 1991–2020 at Lake Geneva Wwtp, WI, 6.9 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 18 days after the last snow.

Planting calendar for 53128

What to do and when, from the 50% frost dates for Genoa City, Wisconsin
WhenWhat to do
February 19 – March 5Start peppers and aubergines indoorsThey need eight to ten weeks under lights before they can go out.
March 5 – March 19Start tomatoes indoorsSix to eight weeks gives a transplant big enough to set fruit early.
April 2 – April 16Sow peas, spinach, lettuce, radish outdoorsThese tolerate light frost and prefer to germinate in cool soil.
April 30 onwardTransplant tomatoes, peppers, basil, squash, cucumbersThe average last freeze has passed — still watch the actual forecast.
by July 21Sow the autumn crop of carrots, beets and brassicasThey need about twelve weeks to size up before growth stops.
by September 29Harvest tender crops, or be ready to cover themA first freeze two weeks early is well within normal variation.
October 13 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 53128 is under a mile from Pell Lake, WI, which stands at 840 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 3 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 53128 in zone 5b, the band where the coldest night of the year averaged -15 to -10°F (-26.1 to -23.3°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 5b places in Wisconsin