Hillsboro, Wisconsin climate: Normal weather by month, frost dates and records
Hillsboro's normal year runs from 7°F January nights to 83°F July afternoons, with 37.3 inches of precipitation and 39 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 7.8°C, January lows of −14°C, July highs of 28°C, 947 mm of precipitation a year.
- NOAA stationHillsboro
- Station IDUSC00473654
- Location43.65°N 90.33°W
- Elevation940 ft (287 m)
- Population1,397
On October 23, the normal high in Hillsboro is 57°F and the normal low 35°F, and the chance of measurable rain or snow is 30%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Hillsboro.
- Jan 27° 7°
- Feb 32° 10°
- Mar 44° 23°
- Apr 58° 34°
- May 69° 46°
- Jun 79° 56°
- Jul 83° 60°
- Aug 81° 58°
- Sep 74° 49°
- Oct 60° 37°
- Nov 46° 27°
- 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 Hillsboro each month?
July is the warmest month, with normal highs of 83°F; January the coldest, with normal lows of 7°F. The most precipitation falls in June (5.08 in), the least in February (1.19 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 27°F | 7°F | 16.9°F | 1.31 | 10.0 | 9 | <1 | 30 | 9 h 20 min |
| February | 32°F | 10°F | 21.1°F | 1.19 | 10.0 | 8 | <1 | 27 | 10 h 30 min |
| March | 44°F | 23°F | 33.1°F | 2.03 | 6.4 | 9 | <1 | 26 | 11 h 50 min |
| April | 58°F | 34°F | 45.9°F | 3.77 | 2.1 | 11 | <1 | 13 | 13 h 20 min |
| May | 69°F | 46°F | 57.4°F | 5.00 | 0.0 | 14 | <1 | 2 | 14 h 40 min |
| June | 79°F | 56°F | 67.4°F | 5.08 | 0.0 | 12 | 1 | <1 | 15 h 30 min |
| July | 83°F | 60°F | 71.3°F | 4.13 | 0.0 | 11 | 3 | <1 | 15 h 10 min |
| August | 81°F | 58°F | 69.4°F | 4.15 | 0.0 | 11 | 2 | <1 | 14 h |
| September | 74°F | 49°F | 61.2°F | 4.05 | 0.0 | 10 | <1 | 1 | 12 h 30 min |
| October | 60°F | 37°F | 48.8°F | 2.84 | 0.2 | 10 | <1 | 11 | 11 h 10 min |
| November | 46°F | 27°F | 36.1°F | 2.12 | 2.6 | 8 | <1 | 23 | 9 h 40 min |
| December | 33°F | 15°F | 23.6°F | 1.62 | 7.4 | 9 | <1 | 30 | 9 h |
| Year (annual) | 57°F | 35°F | 46.0°F | 37.29 | 38.7 | 122 | 6 | 163 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −3°C | −14°C | −8.4°C | 33 mm | 25 cm |
| February | 0°C | −12°C | −6.1°C | 30 mm | 25 cm |
| March | 7°C | −5°C | 0.6°C | 52 mm | 16 cm |
| April | 14°C | 1°C | 7.7°C | 96 mm | 5 cm |
| May | 21°C | 8°C | 14.1°C | 127 mm | 0 cm |
| June | 26°C | 13°C | 19.7°C | 129 mm | 0 cm |
| July | 28°C | 16°C | 21.8°C | 105 mm | 0 cm |
| August | 27°C | 15°C | 20.8°C | 105 mm | 0 cm |
| September | 23°C | 9°C | 16.2°C | 103 mm | 0 cm |
| October | 16°C | 3°C | 9.3°C | 72 mm | 1 cm |
| November | 8°C | −3°C | 2.3°C | 54 mm | 7 cm |
| December | 0°C | −10°C | −4.7°C | 41 mm | 19 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00473654; 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 Hillsboro?
Normal highs sit between 65°F and 85°F in May, June, July, 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 USC00473654.
When is the last frost in Hillsboro?
In Hillsboro, the last spring frost (32°F) comes after May 5 in half of years and after May 18 in one year in ten; the first autumn frost comes before October 4 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 51 year in 10 after May 18; 9 in 10 after April 22
- First autumn frost, half of years before
- October 41 year in 10 before September 23; 9 in 10 before October 18
NOAA puts the median frost-free season at 153 days, and the season without a hard freeze (28°F) at 176 days.
A hard freeze (28°F) comes after April 23 in half of springs and before October 17 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Hillsboro in zone 4b in ZIP code 53962, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Hillsboro's NOAA station is in zone 4b: the coldest night of a typical year reaches −23°F (19 complete years).
Frost dates for every NOAA station in Wisconsin · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00473654; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. 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 Hillsboro?
In a normal year in Hillsboro, 6 days a year reach 90°F, 163 nights fall to 32°F or colder and 122 days bring measurable precipitation.
- Days at 90°F or more
- 6a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 163a normal year
- Days that stay below freezing
- 62high of 32°F or less
- Days with 0.01 inch of precipitation
- 122a normal year
- Days with 1 inch of snow or more
- 15a normal year
The highest temperature in this station's record (since 1959) is 101°F, on August 17, 1988; the lowest is −44°F, on January 15, 1963.
The wettest calendar year on that record is 2007, with 41.91 in; the snowiest season is 2007–08, with 84.6 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00473654; records: ACIS (NOAA Regional Climate Centers), station USC00473654. Records use complete months only; a month missing more than three days is left out.
How sunny is Hillsboro?
Over a year 73% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Hillsboro, 3.9 kWh per square metre a day. July is the sunniest month (80%) and December the cloudiest (62%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 69% | 1.8 |
| February | 75% | 2.9 |
| March | 72% | 3.9 |
| April | 67% | 4.6 |
| May | 70% | 5.5 |
| June | 74% | 6.1 |
| July | 80% | 6.2 |
| August | 78% | 5.3 |
| September | 77% | 4.2 |
| October | 69% | 2.8 |
| November | 67% | 1.8 |
| December | 62% | 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 Hillsboro need?
A normal year in Hillsboro brings 7,454 heating degree days, 39% more than the median U.S. place (5,373), and 581 cooling degree days, 36% 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 2,574 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,489 | 0 |
| February | 1,229 | 0 |
| March | 989 | 0 |
| April | 575 | 3 |
| May | 263 | 27 |
| June | 55 | 125 |
| July | 11 | 208 |
| August | 24 | 161 |
| September | 163 | 50 |
| October | 508 | 6 |
| November | 867 | 0 |
| December | 1,282 | 0 |
| Year (annual) | 7,454 | 581 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00473654. 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.
How does Hillsboro's climate compare?
Hillsboro is warmer than 106 of the other 164 places with their own NOAA record in Wisconsin, and wetter than 129. Across the 7,247 U.S. stations with normals, its annual mean of 46.0°F is warmer than 23%.
In the Köppen classification computed from these normals, Hillsboro 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 Hillsboro share this climate record?
5 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.
- Elroy, WI1,267 people · 7 mi NE
- Wonewoc, WI727 people · 5 mi E
- Kendall, WI469 people · 10 mi N
- Union Center, WI219 people · 4 mi NE
- Yuba, WI51 people · 9 mi SW
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
What do Hillsboro's other NOAA stations record?
One more NOAA station keeps 1991-2020 normals in or near Hillsboro. This page uses Hillsboro; the other differs by site and elevation:
| Station | From this station | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Hillsboro (2 mi SW) USC00473650 | 3 mi SW | 1,043 ft | 43.6°F | 6°F | 80°F | 36.2 | – | May 12 |
Source: NOAA NCEI 1991-2020 normals for each station. Last frost: the median last spring date of 32°F.
Questions about Hillsboro's climate
What is the coldest month in Hillsboro?
January, with a normal high of 27°F and a normal low of 7°F. The warmest is July (83°F by day, 60°F at night).
Does it snow in Hillsboro?
Yes: 39 inches in a normal year, falling on 27 days with 0.1 inch or more, the most in January (10.0 inches).
What is the rainiest month in Hillsboro?
June, with 5.08 in of precipitation in a normal year; the driest is February with 1.19 in.
What plant hardiness zone is Hillsboro in?
The USDA's 2023 map puts Hillsboro in zone 4b in ZIP code 53962, the nearest ZIP area. By the same method at Hillsboro's NOAA station, the coldest night of a typical year reaches −23°F (19 years, 1991-2020): zone 4b.
How late can frost come in Hillsboro?
In half of years the last 32°F night comes after May 5; 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
- Mauston, WI17 miles from this station, 45.8°F a year
- Reedsburg, WI19 miles from this station, 46.3°F a year
- Richland Center, WI22 miles from this station, 45.8°F a year
- Cashton, WI23 miles from this station, 46.2°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made