Hill City, South Dakota climate: Normal weather by month, frost dates and records
Hill City's normal year runs from 10°F January nights to 83°F July afternoons, with 22.4 inches of precipitation and 67 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 6.6°C, January lows of −12°C, July highs of 28°C, 568 mm of precipitation a year.
- NOAA stationHill City
- Station IDUSC00393868
- Location43.93°N 103.56°W
- Elevation4,946 ft (1,508 m)
- Population937
On October 22, the normal high in Hill City is 57°F and the normal low 26°F, and the chance of measurable rain or snow is 23%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Hill City.
- Jan 41° 10°
- Feb 41° 10°
- Mar 49° 19°
- Apr 56° 26°
- May 65° 37°
- Jun 75° 45°
- Jul 83° 51°
- Aug 82° 48°
- Sep 74° 39°
- Oct 60° 28°
- Nov 49° 18°
- Dec 41° 10°
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 Hill City each month?
July is the warmest month, with normal highs of 83°F; January the coldest, with normal lows of 10°F. The most precipitation falls in May (4.15 in), the least in January (0.40 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 41°F | 10°F | 25.1°F | 0.40 | 6.1 | 5 | <1 | 31 | 9 h 10 min |
| February | 41°F | 10°F | 25.5°F | 0.65 | 8.7 | 7 | <1 | 28 | 10 h 30 min |
| March | 49°F | 19°F | 34.0°F | 1.12 | 11.6 | 7 | <1 | 29 | 11 h 50 min |
| April | 56°F | 26°F | 41.1°F | 2.46 | 13.8 | 11 | <1 | 24 | 13 h 20 min |
| May | 65°F | 37°F | 50.7°F | 4.15 | 4.1 | 14 | <1 | 10 | 14 h 40 min |
| June | 75°F | 45°F | 60.3°F | 3.43 | 0.3 | 12 | 1 | 1 | 15 h 30 min |
| July | 83°F | 51°F | 66.7°F | 3.55 | 0.0 | 12 | 4 | <1 | 15 h 10 min |
| August | 82°F | 48°F | 65.0°F | 2.34 | 0.0 | 10 | 3 | <1 | 14 h |
| September | 74°F | 39°F | 56.2°F | 1.54 | 1.0 | 8 | 1 | 7 | 12 h 40 min |
| October | 60°F | 28°F | 43.8°F | 1.65 | 6.5 | 8 | <1 | 23 | 11 h 10 min |
| November | 49°F | 18°F | 33.2°F | 0.59 | 7.5 | 5 | <1 | 29 | 9 h 40 min |
| December | 41°F | 10°F | 25.4°F | 0.49 | 7.0 | 5 | <1 | 31 | 9 h |
| Year (annual) | 60°F | 28°F | 43.9°F | 22.37 | 66.6 | 104 | 8 | 212 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 5°C | −12°C | −3.8°C | 10 mm | 15 cm |
| February | 5°C | −12°C | −3.6°C | 17 mm | 22 cm |
| March | 9°C | −7°C | 1.1°C | 28 mm | 29 cm |
| April | 13°C | −3°C | 5.1°C | 62 mm | 35 cm |
| May | 18°C | 3°C | 10.4°C | 105 mm | 10 cm |
| June | 24°C | 7°C | 15.7°C | 87 mm | 1 cm |
| July | 28°C | 10°C | 19.3°C | 90 mm | 0 cm |
| August | 28°C | 9°C | 18.3°C | 59 mm | 0 cm |
| September | 23°C | 4°C | 13.4°C | 39 mm | 3 cm |
| October | 15°C | −2°C | 6.6°C | 42 mm | 17 cm |
| November | 9°C | −8°C | 0.7°C | 15 mm | 19 cm |
| December | 5°C | −12°C | −3.7°C | 12 mm | 18 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00393868; 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 Hill City?
Normal highs sit between 65°F and 85°F in June, July, August and September. Of those, September has the fewest days with rain (8).
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 USC00393868.
When is the last frost in Hill City?
In Hill City, the last spring frost (32°F) comes after June 1 in half of years and after June 19 in one year in ten; the first autumn frost comes before September 10 in half of years and before August 29 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
- June 11 year in 10 after June 19; 9 in 10 after May 18
- First autumn frost, half of years before
- September 101 year in 10 before August 29; 9 in 10 before September 26
NOAA puts the median frost-free season at 102 days, and the season without a hard freeze (28°F) at 126 days.
A hard freeze (28°F) comes after May 18 in half of springs and before September 21 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Hill City in zone 5a in ZIP code 57751, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Hill City's NOAA station is in zone 4b: the coldest night of a typical year reaches −24°F (30 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in South Dakota · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00393868; 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 Hill City?
In a normal year in Hill City, 8 days a year reach 90°F, 212 nights fall to 32°F or colder and 104 days bring measurable precipitation.
- Days at 90°F or more
- 8a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 212a normal year
- Days that stay below freezing
- 35high of 32°F or less
- Days with 0.01 inch of precipitation
- 104a normal year
- Days with 1 inch of snow or more
- 21a normal year
The highest temperature in this station's record (since 1968) is 101°F, on July 30, 2006; the lowest is −39°F, on December 22, 1990.
The wettest calendar year on that record is 2018, with 31.60 in; the snowiest season is 2013–14, with 112.5 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00393868; records: ACIS (NOAA Regional Climate Centers), station USC00393868. Records use complete months only; a month missing more than three days is left out.
How sunny is Hill City?
Over a year 79% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Hill City, 4.4 kWh per square metre a day. July is the sunniest month (86%) and April the cloudiest (72%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 78% | 2.1 |
| February | 75% | 3.0 |
| March | 74% | 4.1 |
| April | 72% | 5.1 |
| May | 73% | 6.0 |
| June | 82% | 7.0 |
| July | 86% | 7.1 |
| August | 86% | 6.1 |
| September | 83% | 4.8 |
| October | 77% | 3.3 |
| November | 77% | 2.3 |
| December | 75% | 1.8 |
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 Hill City need?
A normal year in Hill City brings 7,881 heating degree days, 47% more than the median U.S. place (5,373), and 227 cooling degree days, 75% fewer than the median (908). Eight months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 1,697 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,239 | 0 |
| February | 1,107 | 0 |
| March | 960 | 0 |
| April | 719 | 0 |
| May | 447 | 3 |
| June | 172 | 31 |
| July | 52 | 106 |
| August | 72 | 74 |
| September | 279 | 13 |
| October | 656 | 0 |
| November | 954 | 0 |
| December | 1,226 | 0 |
| Year (annual) | 7,881 | 227 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00393868. 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 Hill City been warmer than normal lately?
2025 averaged 43.3°F, 0.6°F below the 1991-2020 normal of 43.9°F. 1 of the 4 complete years since 2022 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2022 | 41.7°F | −2.2°F | 18.16 | 38.4 |
| 2023 | 42.5°F | −1.4°F | 28.89 | 71.5 |
| 2024 | 44.5°F | +0.6°F | 15.55 | 27.3 |
| 2025 | 43.3°F | −0.6°F | 23.05 | 35.6 |
Over 30 complete years from 1990 to 2025, the station's annual mean temperature rose at a fitted 2.9°F per century (+0.16°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00393868; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Hill City's climate compare?
Hill City is warmer than 21 of the other 99 places with their own NOAA record in South Dakota, and wetter than 46. Across the 7,247 U.S. stations with normals, its annual mean of 43.9°F is warmer than 15%.
In the Köppen classification computed from these normals, Hill City is Dwb: continental, dry-winter, 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.
Questions about Hill City's climate
What is the coldest month in Hill City?
January, with a normal high of 41°F and a normal low of 10°F. The warmest is July (83°F by day, 51°F at night).
Does it snow in Hill City?
Yes: 67 inches in a normal year, falling on 34 days with 0.1 inch or more, the most in April (13.8 inches).
What is the rainiest month in Hill City?
May, with 4.15 in of precipitation in a normal year; the driest is January with 0.40 in.
What plant hardiness zone is Hill City in?
The USDA's 2023 map puts Hill City in zone 5a in ZIP code 57751, the nearest ZIP area. By the same method at Hill City's NOAA station, the coldest night of a typical year reaches −24°F (30 years, 1991-2020): zone 4b.
How late can frost come in Hill City?
In half of years the last 32°F night comes after June 1; in one year in ten it comes after June 19. Waiting until June 19 leaves about a one-in-ten chance of a later frost.
Nearby and next
- South Dakota climateThe statewide normals and every place in the state
- Mount Rushmore National Memorial, SD6 miles from this station, 45.7°F a year
- Pactola Dam, SD9 miles from this station, 42.1°F a year
- Johnson Siding, SD12 miles from this station, 45.1°F a year
- Custer, SD14 miles from this station, 43.1°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made