Sauk City, Wisconsin climate: Normal weather by month, frost dates and records
Sauk City's normal year runs from 8°F January nights to 82°F July afternoons, with 36.5 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 7.7°C, January lows of −13°C, July highs of 28°C, 928 mm of precipitation a year.
- NOAA stationSauk City Wastewater Treatment Plant
- Station IDUSC00477576
- Location43.26°N 89.73°W
- Elevation750 ft (229 m)
- Population3,471
On October 14, the normal high in Sauk City is 62°F and the normal low 39°F, and the chance of measurable rain or snow is 38%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Sauk City.
- Jan 27° 8°
- Feb 31° 11°
- Mar 44° 23°
- Apr 57° 34°
- May 69° 46°
- Jun 79° 56°
- Jul 82° 59°
- Aug 80° 58°
- Sep 74° 49°
- Oct 61° 38°
- Nov 45° 26°
- Dec 33° 15°
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 Sauk City each month?
July is the warmest month, with normal highs of 82°F; January the coldest, with normal lows of 8°F. The most precipitation falls in June (5.32 in), the least in January (1.30 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 27°F | 8°F | 17.2°F | 1.30 | 9 | <1 | 30 | 9 h 20 min |
| February | 31°F | 11°F | 20.9°F | 1.33 | 9 | <1 | 27 | 10 h 30 min |
| March | 44°F | 23°F | 33.2°F | 1.93 | 9 | <1 | 25 | 11 h 50 min |
| April | 57°F | 34°F | 45.2°F | 3.86 | 12 | <1 | 14 | 13 h 20 min |
| May | 69°F | 46°F | 57.3°F | 4.33 | 13 | 1 | 2 | 14 h 40 min |
| June | 79°F | 56°F | 67.3°F | 5.32 | 13 | 2 | <1 | 15 h 20 min |
| July | 82°F | 59°F | 70.7°F | 4.24 | 10 | 4 | <1 | 15 h 10 min |
| August | 80°F | 58°F | 69.0°F | 4.12 | 10 | 2 | <1 | 14 h |
| September | 74°F | 49°F | 61.2°F | 3.94 | 10 | 1 | 1 | 12 h 30 min |
| October | 61°F | 38°F | 49.1°F | 2.38 | 12 | <1 | 11 | 11 h 10 min |
| November | 45°F | 26°F | 35.5°F | 2.23 | 9 | <1 | 22 | 9 h 50 min |
| December | 33°F | 15°F | 23.8°F | 1.54 | 10 | <1 | 29 | 9 h |
| Year (annual) | 57°F | 35°F | 45.9°F | 36.52 | 126 | 9 | 160 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | −3°C | −13°C | −8.2°C | 33 mm |
| February | −1°C | −12°C | −6.2°C | 34 mm |
| March | 7°C | −5°C | 0.7°C | 49 mm |
| April | 14°C | 1°C | 7.3°C | 98 mm |
| May | 21°C | 8°C | 14.1°C | 110 mm |
| June | 26°C | 13°C | 19.6°C | 135 mm |
| July | 28°C | 15°C | 21.5°C | 108 mm |
| August | 27°C | 14°C | 20.6°C | 105 mm |
| September | 23°C | 9°C | 16.2°C | 100 mm |
| October | 16°C | 3°C | 9.5°C | 60 mm |
| November | 7°C | −3°C | 1.9°C | 57 mm |
| December | 0°C | −9°C | −4.6°C | 39 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Mazomanie (8 miles away), gets 30 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00477576; 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 Sauk City?
Normal highs sit between 65°F and 85°F in May, June, July, August and September. Of those, July 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 USC00477576.
When is the last frost in Sauk City?
In Sauk City, the last spring frost (32°F) comes after May 4 in half of years and after May 18 in one year in ten; the first autumn frost comes before October 6 in half of years and before September 23 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
- May 41 year in 10 after May 18; 9 in 10 after April 20
- First autumn frost, half of years before
- October 61 year in 10 before September 23; 9 in 10 before October 21
NOAA puts the median frost-free season at 155 days, and the season without a hard freeze (28°F) at 177 days.
A hard freeze (28°F) comes after April 23 in half of springs and before October 19 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Sauk City in zone 5a in ZIP code 53578, 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 USC00477576; 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 Sauk City?
In a normal year in Sauk City, 9 days a year reach 90°F (1 of them 100°F or more), 160 nights fall to 32°F or colder and 126 days bring measurable precipitation.
- Days at 90°F or more
- 9a normal year
- Days at 100°F or more
- 1a normal year
- Nights at 32°F or colder
- 160a normal year
- Days that stay below freezing
- 61high of 32°F or less
- Days with 0.01 inch of precipitation
- 126a normal year
Source: NOAA NCEI 1991-2020 annual normals, station USC00477576.
How sunny is Sauk City?
Over a year 72% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Sauk City, 3.9 kWh per square metre a day. July is the sunniest month (80%) and December the cloudiest (60%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 66% | 1.7 |
| February | 73% | 2.8 |
| March | 72% | 3.8 |
| April | 67% | 4.6 |
| May | 70% | 5.5 |
| June | 75% | 6.1 |
| July | 80% | 6.2 |
| August | 78% | 5.3 |
| September | 77% | 4.2 |
| October | 68% | 2.8 |
| November | 66% | 1.8 |
| December | 60% | 1.3 |
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 Sauk City need?
A normal year in Sauk City brings 7,463 heating degree days, 39% more than the median U.S. place (5,373), and 530 cooling degree days, 42% 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 2,523 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,482 | 0 |
| February | 1,235 | 0 |
| March | 987 | 1 |
| April | 593 | 1 |
| May | 265 | 28 |
| June | 45 | 112 |
| July | 13 | 189 |
| August | 26 | 148 |
| September | 161 | 47 |
| October | 497 | 4 |
| November | 884 | 0 |
| December | 1,277 | 0 |
| Year (annual) | 7,463 | 530 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00477576. 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 Sauk City been warmer than normal lately?
2025 averaged 47.1°F, 1.2°F above the 1991-2020 normal of 45.9°F. 4 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 47.4°F | +1.5°F | 28.20 |
| 2022 | 44.9°F | −1.0°F | 37.55 |
| 2023 | 48.5°F | +2.6°F | 28.60 |
| 2024 | 49.3°F | +3.4°F | 51.17 |
| 2025 | 47.1°F | +1.2°F | 32.66 |
Source: observed years: ACIS, station USC00477576. A year counts only with all twelve months complete.
How does Sauk City's climate compare?
Sauk City is warmer than 104 of the other 164 places with their own NOAA record in Wisconsin, and wetter than 119. Across the 7,247 U.S. stations with normals, its annual mean of 45.9°F is warmer than 23%.
In the Köppen classification computed from these normals, Sauk City is Dfb: continental, no dry season, warm 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 Sauk City share this climate record?
Prairie du Sac has no NOAA station with 1991-2020 normals of its 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.
- Prairie du Sac, WI4,358 people · 2 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 Sauk City's climate
What is the coldest month in Sauk City?
January, with a normal high of 27°F and a normal low of 8°F. The warmest is July (82°F by day, 59°F at night).
Does it snow in Sauk City?
Yes. NOAA publishes no 1991-2020 snowfall normal for Sauk City's NOAA station; the nearest record that keeps one, Mazomanie (8 miles away), records 30 inches of snow in a normal year.
What is the rainiest month in Sauk City?
June, with 5.32 in of precipitation in a normal year; the driest is January with 1.30 in.
What plant hardiness zone is Sauk City in?
The USDA's 2023 map puts Sauk City in zone 5a in ZIP code 53578, the nearest ZIP area.
How late can frost come in Sauk City?
In half of years the last 32°F night comes after May 4; in one year in ten it comes after May 18. Waiting until May 18 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Wisconsin climateThe statewide normals and every place in the state
- Mazomanie, WI7 miles from this station, 45.8°F a year
- Lodi, WI11 miles from this station, 47.1°F a year
- Baraboo, WI14 miles from this station, 46.6°F a year
- Rock Springs, WI17 miles from this station, 46.6°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made