Lake Geneva, Wisconsin climate: Normal weather by month, frost dates and records
Lake Geneva's normal year runs from 15°F January nights to 86°F July afternoons, with 37.0 inches of precipitation and 40 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 9.7°C, January lows of −9°C, July highs of 30°C, 939 mm of precipitation a year.
- NOAA stationLake Geneva Wastewater Treatment Plant
- Station IDUSC00474457
- Location42.60°N 88.43°W
- Elevation846 ft (258 m)
- Population8,691
On October 14, the normal high in Lake Geneva is 64°F and the normal low 43°F, and the chance of measurable rain or snow is 33%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Lake Geneva.
- Jan 30° 15°
- Feb 35° 17°
- Mar 45° 26°
- Apr 59° 37°
- May 72° 48°
- Jun 81° 58°
- Jul 86° 63°
- Aug 83° 61°
- Sep 76° 54°
- Oct 63° 42°
- Nov 47° 31°
- Dec 35° 21°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Lake Geneva each month?
July is the warmest month, with normal highs of 86°F; January the coldest, with normal lows of 15°F. The most precipitation falls in June (4.81 in), the least in February (1.89 in).
Each month has its own page with the day-by-day normals, the month's records and its recent years:
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 30°F | 15°F | 22.6°F | 1.90 | 13.9 | 12 | <1 | 29 | 9 h 20 min |
| February | 35°F | 17°F | 25.7°F | 1.89 | 8.1 | 9 | <1 | 25 | 10 h 30 min |
| March | 45°F | 26°F | 35.7°F | 2.29 | 4.8 | 10 | <1 | 23 | 11 h 50 min |
| April | 59°F | 37°F | 48.1°F | 3.45 | 2.6 | 13 | <1 | 9 | 13 h 20 min |
| May | 72°F | 48°F | 60.0°F | 4.12 | 0.0 | 13 | 1 | 1 | 14 h 30 min |
| June | 81°F | 58°F | 69.6°F | 4.81 | 0.0 | 11 | 6 | <1 | 15 h 20 min |
| July | 86°F | 63°F | 74.3°F | 3.72 | 0.0 | 9 | 8 | <1 | 15 h |
| August | 83°F | 61°F | 72.3°F | 3.32 | 0.0 | 10 | 5 | <1 | 14 h |
| September | 76°F | 54°F | 65.1°F | 3.65 | 0.0 | 10 | 2 | <1 | 12 h 30 min |
| October | 63°F | 42°F | 52.4°F | 3.01 | 0.2 | 10 | <1 | 4 | 11 h 10 min |
| November | 47°F | 31°F | 39.1°F | 2.48 | 3.4 | 11 | <1 | 18 | 9 h 50 min |
| December | 35°F | 21°F | 27.8°F | 2.31 | 7.1 | 11 | <1 | 27 | 9 h |
| Year (annual) | 59°F | 40°F | 49.4°F | 36.95 | 40.1 | 129 | 21 | 136 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −1°C | −9°C | −5.2°C | 48 mm | 35 cm |
| February | 1°C | −8°C | −3.5°C | 48 mm | 21 cm |
| March | 7°C | −3°C | 2.1°C | 58 mm | 12 cm |
| April | 15°C | 3°C | 8.9°C | 88 mm | 7 cm |
| May | 22°C | 9°C | 15.6°C | 105 mm | 0 cm |
| June | 27°C | 15°C | 20.9°C | 122 mm | 0 cm |
| July | 30°C | 17°C | 23.5°C | 94 mm | 0 cm |
| August | 29°C | 16°C | 22.4°C | 84 mm | 0 cm |
| September | 25°C | 12°C | 18.4°C | 93 mm | 0 cm |
| October | 17°C | 6°C | 11.3°C | 76 mm | 1 cm |
| November | 9°C | −1°C | 3.9°C | 63 mm | 9 cm |
| December | 2°C | −6°C | −2.3°C | 59 mm | 18 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00474457; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Lake Geneva?
Normal highs sit between 65°F and 85°F in May, June, August and September. Of those, September has the fewest days with rain (10).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00474457.
When is the last frost in Lake Geneva?
In Lake Geneva, the last spring frost (32°F) comes after April 25 in half of years and after May 10 in one year in ten; the first autumn frost comes before October 21 in half of years and before October 5 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- April 251 year in 10 after May 10; 9 in 10 after April 10
- First autumn frost, half of years before
- October 211 year in 10 before October 5; 9 in 10 before November 3
NOAA puts the median frost-free season at 179 days, and the season without a hard freeze (28°F) at 203 days.
A hard freeze (28°F) comes after April 12 in half of springs and before November 1 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Lake Geneva in zone 5b in ZIP code 53147, the nearest ZIP area.
Frost dates for every NOAA station in Wisconsin · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00474457; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get in Lake Geneva?
In a normal year in Lake Geneva, 21 days a year reach 90°F (1 of them 100°F or more), 136 nights fall to 32°F or colder and 129 days bring measurable precipitation.
- Days at 90°F or more
- 21a normal year
- Days at 100°F or more
- 1a normal year
- Nights at 32°F or colder
- 136a normal year
- Days that stay below freezing
- 48high of 32°F or less
- Days with 0.01 inch of precipitation
- 129a normal year
- Days with 1 inch of snow or more
- 14a normal year
The highest temperature in this station's record (since 1945) is 106°F, on August 1, 1988; the lowest is −27°F, on January 20, 1985.
The wettest calendar year on that record is 1972, with 49.97 in; the snowiest season is 1978–79, with 79.4 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00474457; records: ACIS (NOAA Regional Climate Centers), station USC00474457. Records use complete months only; a month missing more than three days is left out.
How sunny is Lake Geneva?
Over a year 72% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Lake Geneva, 3.9 kWh per square metre a day. July is the sunniest month (80%) and December the cloudiest (61%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 63% | 1.7 |
| February | 67% | 2.6 |
| March | 67% | 3.6 |
| April | 69% | 4.7 |
| May | 70% | 5.5 |
| June | 76% | 6.1 |
| July | 80% | 6.3 |
| August | 79% | 5.4 |
| September | 78% | 4.3 |
| October | 69% | 2.8 |
| November | 66% | 1.9 |
| December | 61% | 1.4 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Lake Geneva need?
A normal year in Lake Geneva brings 6,513 heating degree days, 21% more than the median U.S. place (5,373), and 867 cooling degree days, 4% fewer than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 3,091 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,316 | 0 |
| February | 1,099 | 0 |
| March | 907 | 0 |
| April | 511 | 5 |
| May | 206 | 51 |
| June | 38 | 175 |
| July | 3 | 291 |
| August | 8 | 236 |
| September | 96 | 97 |
| October | 400 | 11 |
| November | 777 | 0 |
| December | 1,153 | 0 |
| Year (annual) | 6,513 | 867 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00474457. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Lake Geneva been warmer than normal lately?
2025 averaged 47.4°F, 2.0°F below the 1991-2020 normal of 49.4°F. 1 of the 3 complete years since 2023 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2023 | 49.2°F | −0.2°F | 33.56 | 33.4 |
| 2024 | 50.1°F | +0.8°F | 42.26 | 28.7 |
| 2025 | 47.4°F | −2.0°F | 31.78 | 34.1 |
Over 55 complete years from 1946 to 2025, the station's annual mean temperature rose at a fitted 3.1°F per century (+0.17°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00474457; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Lake Geneva's climate compare?
Lake Geneva is warmer than 164 of the other 164 places with their own NOAA record in Wisconsin, and wetter than 124. Across the 7,247 U.S. stations with normals, its annual mean of 49.4°F is warmer than 38%.
In the Köppen classification computed from these normals, Lake Geneva is Dfa: continental, no dry season, hot summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Lake Geneva share this climate record?
4 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Williams Bay, WI2,961 people · 6 mi W
- Como, WI2,368 people · 3 mi W
- Lyons, WI1,206 people · 5 mi NE
- Springfield, WI154 people · 3 mi N
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Lake Geneva's climate
What is the coldest month in Lake Geneva?
January, with a normal high of 30°F and a normal low of 15°F. The warmest is July (86°F by day, 63°F at night).
Does it snow in Lake Geneva?
Yes: 40 inches in a normal year, falling on 32 days with 0.1 inch or more, the most in January (13.9 inches).
What is the rainiest month in Lake Geneva?
June, with 4.81 in of precipitation in a normal year; the driest is February with 1.89 in.
What plant hardiness zone is Lake Geneva in?
The USDA's 2023 map puts Lake Geneva in zone 5b in ZIP code 53147, the nearest ZIP area.
How late can frost come in Lake Geneva?
In half of years the last 32°F night comes after April 25; in one year in ten it comes after May 10. Waiting until May 10 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Lake Geneva in OctoberThis month day by day, its records and recent years
- Wisconsin climateThe statewide normals and every place in the state
- Pell Lake, WI7 miles from this station, 47.0°F a year
- Burlington, WI9 miles from this station, 46.1°F a year
- Delavan, WI12 miles from this station, 47.6°F a year
- Rochester, WI14 miles from this station, 46.7°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made