Utah

Millard County, Utah Climate

NOAA 1991-2020 normals for Black Rock, 42.7 km from Millard County

The warmest month is July, with an average high of 95°F; the coldest is December, with an average low of 16°F. A normal year brings 8.8 in of precipitation and 23.7 in of snow.

Temperature through the year

The normal daily high and low and the record for every date at Delta (DTA), since 1938. The line marks today.

Normal daily high and low temperature at Millard County through the year, in °F, with the record for each date.-50050100150JanFebMarAprMayJunJulAugSepOctNovDec
  • Normal low
  • Normal high
  • Record high
  • Record low

Normals for Sep 24

Normal high
79°F
Normal low
41°F
Record high
95°Fin 2001
Record low
26°Fin 2000
Chance of a wet day
13%
Daylight
12 h 04 min

Month by month

Averages for 1991-2020. Wet days have at least 0.01 inch of precipitation. Freeze nights have a low of 32°F or colder; degree days are on a 65°F base. Each month links to its own page.

MonthAvg highAvg lowRecord highRecord lowPrecipitationWet daysSnowfallFreeze nightsHeating DDCooling DD
January42°F16°F64°F (1953)-25°F (1971)0.59 in4.35.5 in29.21,1070
February49°F21°F74°F (1972)-27°F (1989)0.72 in5.04.7 in25.18410
March61°F27°F93°F (2026)-8°F (1966)0.84 in4.83.0 in24.66620
April68°F32°F94°F (2012)12°F (1997)0.95 in5.91.7 in17.04641
May77°F39°F103°F (2003)15°F (2008)0.93 in5.30.1 in5.323516
June88°F47°F107°F (2021)25°F (2001)0.46 in3.00.0 in0.555127
July95°F56°F110°F (2002)37°F (1992)0.58 in4.10.0 in0.02314
August92°F54°F110°F (1938)35°F (1992)0.73 in4.70.0 in0.15248
September83°F44°F106°F (2022)21°F (2003)0.70 in3.80.0 in2.611054
October69°F32°F93°F (2024)-2°F (1971)0.98 in4.40.1 in17.44461
November54°F23°F79°F (2025)-13°F (2006)0.61 in3.52.4 in25.77970
December42°F16°F72°F (2025)-30°F (1990)0.71 in4.56.2 in29.21,1240
Year68°F34°F8.80 in5323.7 in1775,846760

Precipitation

Rain and melted snow together. The chance of a wet day is the share of days with at least 0.01 inch of precipitation.

8.8 in in a normal year, most in October.

Chance of a wet day

The chance of at least 0.01 inch of precipitation on each date at Millard County, in percent, and of at least 0.1 inch of snowfall.05101520JanFebMarAprMayJunJulAugSepOctNovDec
  • Chance of a wet day
  • Chance of snowfall

Snow

NOAA 1991-2020 snowfall normals for Black Rock.

23.7 in of snow in a normal year.

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Black Rock. A median date has an even chance of a later freeze in spring, or an earlier one in fall.

The last spring freeze typically comes around May 23 and the first fall freeze around September 27, a growing season of about 124 days.

Median at 36°F
last June 7, first September 17
Median at 32°F
last May 23, first September 27
Median at 28°F
last May 7, first October 5

Frost dates, growing season and degree days

Humidity and comfort

NASA POWER reanalysis, 1991-2020, for the grid cell around Millard County.

Days with a mean dew point of 65°F or more are rare here in every month.

MonthDew pointHumidityDryComfortableHumidMuggyOppressiveMiserable
January20°F67%100%0%0%0%0%0%
February21°F60%100%0%0%0%0%0%
March24°F52%100%0%0%0%0%0%
April26°F46%100%0%0%0%0%0%
May32°F41%100%0%0%0%0%0%
June33°F31%100%0%0%0%0%0%
July40°F29%94%6%0%0%0%0%
August40°F31%97%3%0%0%0%0%
September33°F34%99%1%0%0%0%0%
October27°F43%100%0%0%0%0%0%
November22°F54%100%0%0%0%0%0%
December19°F65%100%0%0%0%0%0%

Comfort is judged by the day's mean dew point: dry below 55°F, comfortable to 60°F, humid to 65°F, muggy to 70°F, oppressive to 75°F, miserable above.

Clouds

Average share of the sky covered, from satellite (CERES and GEWEX SRB) by way of NASA POWER, 1991-2020.

The clearest month is September, with the sky 33 percent covered on average; the cloudiest is December, at 62 percent.

Wind

The mean wind speed over the whole day, from the MERRA-2 reanalysis by way of NASA POWER. Gusts run well above it.

The windiest month is April, averaging 9.2 mph at 10 meters (33 feet) above the ground.

Daylight and sunshine

The longest day is Jun 16, with 14 h 55 min of daylight; the shortest is Dec 18, with 9 h 25 min.

Hours of daylight at Millard County through the year.0510152025JanFebMarAprMayJunJulAugSepOctNovDec
  • Day length

Solar energy

Average daily sunshine reaching the ground on a flat surface, in kilowatt-hours per square meter, clouds included.

Sunrise and sunset calendar

How Millard County is running

NOAA NCEI Climate at a Glance, from the nClimGrid analysis of every station, updated early each month. A rank of 1 is the highest or lowest of all years since 1895.

August 2026 in Millard County: 77.9°F (+3.6 °F against 1991-2020), the 2nd warmest in 132 years on record.

August 2026 in Millard County: 1.27 in (+0.50 in against 1991-2020), the 26th wettest in 132 years on record.

January to August 2026 in Millard County: 58.4°F (+4.5 °F against 1991-2020), the warmest in 132 years on record.

January to August 2026 in Millard County: 5.15 in (-1.67 in against 1991-2020), the 26th driest in 132 years on record.

Warmest August
79.4°F in 2020
Coolest August
67.1°F in 1968
Wettest August
2.67 in in 1930
Driest August
0.03 in in 2020

Every year since 1895

Each year's average temperature in Millard County against the 1991-2020 average, in °F, 1895 to 2025.-6-4-20+2+4+61900192019401960198020002020NOAA NCEI Climate at a Glance

Utah climate and rankings

Month pages

The weather in Millard County in each month, day by day.

What this means

A normal is the average of the thirty years 1991 to 2020, the period the World Meteorological Organization and NOAA use for comparison. It is an average, not a forecast: most days depart from it, and some by a long way.

A record is the highest or lowest value on the date in every year the station has reported, back to 1938. It rests on one station, so a neighbor a few miles away can hold different ones.

Cloud, humidity, wind and sunshine come from a reanalysis: a weather model run over the past with every observation fed in, averaged over a grid cell about 50 km across. It is consistent everywhere on Earth; it smooths local detail such as a lake shore or a valley.

More for this place

Nearby

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00420730 (Black Rock), public domain. Records: NOAA GHCN-Daily, station USW00023162, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus. Rankings: NOAA NCEI Climate at a Glance, public domain.