Hillsboro, North Dakota climate: Normal weather by month, frost dates and records
Hillsboro's normal year runs from 1°F January nights to 81°F July afternoons, with 22.3 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 5.9°C, January lows of −17°C, July highs of 27°C, 567 mm of precipitation a year.
- NOAA stationHillsboro (3 mi N)
- Station IDUSC00324203
- Location47.44°N 97.07°W
- Elevation910 ft (277 m)
- Population1,661
On October 23, the normal high in Hillsboro is 51°F and the normal low 34°F, and the chance of measurable rain or snow is 22%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Hillsboro.
- Jan 18° 1°
- Feb 23° 4°
- Mar 36° 20°
- Apr 53° 34°
- May 68° 46°
- Jun 77° 57°
- Jul 81° 61°
- Aug 80° 58°
- Sep 71° 50°
- Oct 55° 37°
- Nov 38° 22°
- Dec 24° 9°
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 81°F; January the coldest, with normal lows of 1°F. The most precipitation falls in June (3.65 in), the least in January (0.55 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 18°F | 1°F | 9.4°F | 0.55 | 7 | <1 | 31 | 8 h 50 min |
| February | 23°F | 4°F | 13.3°F | 0.59 | 5 | <1 | 28 | 10 h 10 min |
| March | 36°F | 20°F | 27.7°F | 1.20 | 5 | <1 | 27 | 11 h 50 min |
| April | 53°F | 34°F | 43.4°F | 1.39 | 6 | <1 | 15 | 13 h 30 min |
| May | 68°F | 46°F | 56.7°F | 2.77 | 10 | 1 | 2 | 15 h |
| June | 77°F | 57°F | 67.1°F | 3.65 | 11 | 2 | <1 | 16 h |
| July | 81°F | 61°F | 71.2°F | 3.43 | 9 | 3 | <1 | 15 h 40 min |
| August | 80°F | 58°F | 69.3°F | 2.59 | 8 | 3 | <1 | 14 h 20 min |
| September | 71°F | 50°F | 60.5°F | 2.16 | 7 | 1 | 1 | 12 h 40 min |
| October | 55°F | 37°F | 46.0°F | 2.21 | 7 | <1 | 12 | 11 h |
| November | 38°F | 22°F | 30.3°F | 0.86 | 5 | <1 | 27 | 9 h 20 min |
| December | 24°F | 9°F | 16.6°F | 0.91 | 6 | <1 | 31 | 8 h 30 min |
| Year (annual) | 52°F | 33°F | 42.6°F | 22.31 | 85 | 10 | 174 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | −8°C | −17°C | −12.6°C | 14 mm |
| February | −5°C | −15°C | −10.4°C | 15 mm |
| March | 2°C | −7°C | −2.4°C | 30 mm |
| April | 12°C | 1°C | 6.3°C | 35 mm |
| May | 20°C | 8°C | 13.7°C | 70 mm |
| June | 25°C | 14°C | 19.5°C | 93 mm |
| July | 27°C | 16°C | 21.8°C | 87 mm |
| August | 27°C | 15°C | 20.7°C | 66 mm |
| September | 22°C | 10°C | 15.8°C | 55 mm |
| October | 13°C | 3°C | 7.8°C | 56 mm |
| November | 3°C | −5°C | −0.9°C | 22 mm |
| December | −5°C | −13°C | −8.6°C | 23 mm |
NOAA publishes no 1991-2020 snowfall normal for this station, and no record within 25 miles keeps one, so snow is left out here rather than estimated.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00324203; 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 (7).
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 USC00324203.
When is the last frost in Hillsboro?
In Hillsboro, the last spring frost (32°F) comes after May 2 in half of years and after May 17 in one year in ten; the first autumn frost comes before October 9 in half of years and before September 25 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 21 year in 10 after May 17; 9 in 10 after April 15
- First autumn frost, half of years before
- October 91 year in 10 before September 25; 9 in 10 before October 25
NOAA puts the median frost-free season at 158 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 20 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Hillsboro in zone 4a in ZIP code 58045, the nearest ZIP area.
Frost dates for every NOAA station in North Dakota · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00324203; 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 Hillsboro?
In a normal year in Hillsboro, 10 days a year reach 90°F, 174 nights fall to 32°F or colder and 85 days bring measurable precipitation.
- Days at 90°F or more
- 10a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 174a normal year
- Days that stay below freezing
- 92high of 32°F or less
- Days with 0.01 inch of precipitation
- 85a normal year
The highest temperature in this station's record (since 1905) is 115°F, on July 6, 1936; the lowest is −40°F, on January 30, 1916.
The wettest calendar year on that record is 1998, with 31.16 in; the snowiest season is 1950–51, with 49.0 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00324203; records: ACIS (NOAA Regional Climate Centers), station USC00324203. Records use complete months only; a month missing more than three days is left out.
How sunny is Hillsboro?
Over a year 75% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Hillsboro, 3.8 kWh per square metre a day. February is the sunniest month (86%) and November the cloudiest (65%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 80% | 1.7 |
| February | 86% | 3.0 |
| March | 78% | 4.0 |
| April | 73% | 4.9 |
| May | 71% | 5.6 |
| June | 74% | 6.1 |
| July | 82% | 6.4 |
| August | 80% | 5.3 |
| September | 75% | 3.9 |
| October | 68% | 2.5 |
| November | 65% | 1.5 |
| December | 66% | 1.2 |
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 8,681 heating degree days, 62% more than the median U.S. place (5,373), and 573 cooling degree days, 37% 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 2,465 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,722 | 0 |
| February | 1,446 | 0 |
| March | 1,156 | 0 |
| April | 650 | 1 |
| May | 281 | 25 |
| June | 59 | 123 |
| July | 16 | 208 |
| August | 28 | 161 |
| September | 186 | 51 |
| October | 593 | 4 |
| November | 1,042 | 0 |
| December | 1,502 | 0 |
| Year (annual) | 8,681 | 573 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00324203. 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 74 of the other 91 places with their own NOAA record in North Dakota, and wetter than 67. Across the 7,247 U.S. stations with normals, its annual mean of 42.6°F is warmer than 11%.
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?
8 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.
- Halstad, MN551 people · 13 mi SE
- Buxton, ND353 people · 11 mi N
- Hendrum, MN282 people · 17 mi SE
- Climax, MN241 people · 17 mi NE
- Shelly, MN175 people · 12 mi E
- Nielsville, MN78 people · 13 mi NE
- Caledonia, ND68 people · 8 mi E
- Blanchard, ND0 people · 10 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.
Questions about Hillsboro's climate
What is the coldest month in Hillsboro?
January, with a normal high of 18°F and a normal low of 1°F. The warmest is July (81°F by day, 61°F at night).
What is the rainiest month in Hillsboro?
June, with 3.65 in of precipitation in a normal year; the driest is January with 0.55 in.
What plant hardiness zone is Hillsboro in?
The USDA's 2023 map puts Hillsboro in zone 4a in ZIP code 58045, the nearest ZIP area.
How late can frost come in Hillsboro?
In half of years the last 32°F night comes after May 2; in one year in ten it comes after May 17. Waiting until May 17 leaves about a one-in-ten chance of a later frost.
Nearby and next
- North Dakota climateThe statewide normals and every place in the state
- Mayville, ND14 miles from this station, 39.4°F a year
- Ada, MN27 miles from this station, 40.0°F a year
- Georgetown, MN29 miles from this station, 42.1°F a year
- Colgate, ND30 miles from this station, 38.7°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made