Black Rock, Utah climate: Climate normals at a NOAA weather station
Black Rock's normal year runs from 16°F December nights to 95°F July afternoons, with 8.8 inches of precipitation and 24 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 10.6°C, December lows of −9°C, July highs of 35°C, 224 mm of precipitation a year.
- NOAA stationBlack Rock
- Station IDUSC00420730
- Location38.71°N 112.95°W
- Elevation4,916 ft (1,498 m)
On October 23, the normal high in Black Rock is 66°F and the normal low 30°F, and the chance of measurable rain or snow is 13%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Black Rock.
- Jan 42° 16°
- Feb 49° 21°
- Mar 61° 27°
- Apr 68° 32°
- May 77° 39°
- Jun 88° 47°
- Jul 95° 56°
- Aug 92° 54°
- Sep 83° 44°
- Oct 69° 32°
- Nov 54° 23°
- Dec 42° 16°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like at Black Rock each month?
July is the warmest month, with normal highs of 95°F; December the coldest, with normal lows of 16°F. The most precipitation falls in October (0.98 in), the least in June (0.46 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 42°F | 16°F | 29.3°F | 0.59 | 5.5 | 4 | <1 | 29 | 9 h 40 min |
| February | 49°F | 21°F | 34.9°F | 0.72 | 4.7 | 5 | <1 | 25 | 10 h 40 min |
| March | 61°F | 27°F | 43.6°F | 0.84 | 3.0 | 5 | <1 | 25 | 11 h 50 min |
| April | 68°F | 32°F | 49.5°F | 0.95 | 1.7 | 6 | <1 | 17 | 13 h 10 min |
| May | 77°F | 39°F | 58.0°F | 0.93 | 0.1 | 5 | 2 | 5 | 14 h 20 min |
| June | 88°F | 47°F | 67.4°F | 0.46 | 0.0 | 3 | 13 | 1 | 14 h 50 min |
| July | 95°F | 56°F | 75.1°F | 0.58 | 0.0 | 4 | 26 | <1 | 14 h 40 min |
| August | 92°F | 54°F | 72.9°F | 0.73 | 0.0 | 5 | 21 | <1 | 13 h 40 min |
| September | 83°F | 44°F | 63.2°F | 0.70 | 0.0 | 4 | 5 | 3 | 12 h 30 min |
| October | 69°F | 32°F | 50.6°F | 0.98 | 0.1 | 4 | <1 | 17 | 11 h 20 min |
| November | 54°F | 23°F | 38.5°F | 0.61 | 2.4 | 4 | <1 | 26 | 10 h 10 min |
| December | 42°F | 16°F | 28.7°F | 0.71 | 6.2 | 5 | <1 | 29 | 9 h 30 min |
| Year (annual) | 68°F | 34°F | 51.0°F | 8.80 | 23.7 | 53 | 67 | 177 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 6°C | −9°C | −1.5°C | 15 mm | 14 cm |
| February | 10°C | −6°C | 1.6°C | 18 mm | 12 cm |
| March | 16°C | −3°C | 6.4°C | 21 mm | 8 cm |
| April | 20°C | 0°C | 9.7°C | 24 mm | 4 cm |
| May | 25°C | 4°C | 14.4°C | 24 mm | 0 cm |
| June | 31°C | 8°C | 19.7°C | 12 mm | 0 cm |
| July | 35°C | 13°C | 23.9°C | 15 mm | 0 cm |
| August | 33°C | 12°C | 22.7°C | 19 mm | 0 cm |
| September | 28°C | 7°C | 17.3°C | 18 mm | 0 cm |
| October | 21°C | 0°C | 10.3°C | 25 mm | 0 cm |
| November | 12°C | −5°C | 3.6°C | 15 mm | 6 cm |
| December | 6°C | −9°C | −1.8°C | 18 mm | 16 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00420730; 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.
Which months are mildest at Black Rock?
Normal highs sit between 65°F and 85°F in April, May, September and October. Of those, September has the fewest days with rain (4).
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 USC00420730.
When is the last frost at Black Rock?
In Black Rock, the last spring frost (32°F) comes after May 23 in half of years and after June 11 in one year in ten; the first autumn frost comes before September 27 in half of years and before September 14 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 231 year in 10 after June 11; 9 in 10 after May 5
- First autumn frost, half of years before
- September 271 year in 10 before September 14; 9 in 10 before October 9
NOAA puts the median frost-free season at 124 days, and the season without a hard freeze (28°F) at 150 days.
A hard freeze (28°F) comes after May 7 in half of springs and before October 5 in half of autumns.
By the USDA's method, the average of each year's coldest night over 1991-2020, the station is in plant hardiness zone 5b: the coldest night of a typical year reaches −14°F (30 complete years).
Frost dates for every NOAA station in Utah · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00420730; 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 at Black Rock?
In a normal year in Black Rock, 67 days a year reach 90°F (8 of them 100°F or more), 177 nights fall to 32°F or colder and 53 days bring measurable precipitation.
- Days at 90°F or more
- 67a normal year
- Days at 100°F or more
- 8a normal year
- Nights at 32°F or colder
- 177a normal year
- Days that stay below freezing
- 14high of 32°F or less
- Days with 0.01 inch of precipitation
- 53a normal year
- Days with 1 inch of snow or more
- 7a normal year
The highest temperature in this station's record (since 1900) is 108°F, on July 17, 2023; the lowest is −37°F, on December 23, 1990.
The wettest calendar year on that record is 1998, with 13.41 in; the snowiest season is 1984–85, with 64.5 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00420730; records: ACIS (NOAA Regional Climate Centers), station USC00420730. Records use complete months only; a month missing more than three days is left out.
How sunny is it at Black Rock?
Over a year 83% of the sunlight that would reach the ground under clear skies gets through the clouds at Black Rock, 5.1 kWh per square metre a day. June is the sunniest month (90%) and December the cloudiest (74%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 78% | 2.7 |
| February | 77% | 3.6 |
| March | 78% | 4.9 |
| April | 79% | 6.1 |
| May | 83% | 7.2 |
| June | 90% | 8.1 |
| July | 83% | 7.1 |
| August | 85% | 6.5 |
| September | 88% | 5.7 |
| October | 85% | 4.3 |
| November | 80% | 3.0 |
| December | 74% | 2.3 |
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 many heating and cooling degree days does Black Rock record?
A normal year at Black Rock brings 5,846 heating degree days, 9% more than the median U.S. place (5,373), and 760 cooling degree days, 16% 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 2,891 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,107 | 0 |
| February | 841 | 0 |
| March | 662 | 0 |
| April | 464 | 1 |
| May | 235 | 16 |
| June | 55 | 127 |
| July | 2 | 314 |
| August | 5 | 248 |
| September | 110 | 54 |
| October | 446 | 1 |
| November | 797 | 0 |
| December | 1,124 | 0 |
| Year (annual) | 5,846 | 760 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00420730. 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.
Have recent years at Black Rock been warmer than normal?
2025 averaged 53.1°F, 2.1°F above the 1991-2020 normal of 51.0°F. 3 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 52.0°F | +1.0°F | – | – |
| 2022 | 50.8°F | −0.2°F | 6.72 | – |
| 2023 | 50.2°F | −0.8°F | 8.04 | 39.0 |
| 2024 | 52.9°F | +1.9°F | 12.68 | 12.0 |
| 2025 | 53.1°F | +2.1°F | 7.31 | 4.0 |
Over 67 complete years from 1957 to 2025, the station's annual mean temperature rose at a fitted 2.6°F per century (+0.14°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00420730; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Black Rock's climate compare?
Black Rock is warmer than 62 of the 97 places with their own NOAA record in Utah, and wetter than 21. Across the 7,247 U.S. stations with normals, its annual mean of 51.0°F is warmer than 45%.
In the Köppen classification computed from these normals, Black Rock is BSk: cold semi-arid steppe. 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 Black Rock's climate
What is the coldest month at Black Rock?
December, with a normal high of 42°F and a normal low of 16°F. The warmest is July (95°F by day, 56°F at night).
Does it snow at Black Rock?
Yes: 24 inches in a normal year, falling on 7 days with 0.1 inch or more, the most in December (6.2 inches).
What is the rainiest month at Black Rock?
October, with 0.98 in of precipitation in a normal year; the driest is June with 0.46 in.
What plant hardiness zone is Black Rock in?
By the same method at the station, the coldest night of a typical year reaches −14°F (30 years, 1991-2020): zone 5b.
How late can frost come at Black Rock?
In half of years the last 32°F night comes after May 23; in one year in ten it comes after June 11. Waiting until June 11 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Utah climateThe statewide normals and every place in the state
- Milford, UT21 miles from this station, 51.6°F a year
- Kanosh, UT29 miles from this station, 53.7°F a year
- Wah Wah Ranch, UT30 miles from this station, 51.8°F a year
- Fremont Indian State Park, UT35 miles from this station, 47.1°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made