Arizona

Duncan, Arizona Climate

NOAA 1991-2020 normals for Duncan, 3.3 km from Duncan

The warmest month is June, with an average high of 98°F; the coldest is December, with an average low of 25°F. A normal year brings 10.4 in of precipitation and 1.0 in of snow.

Temperature through the year

The normal daily high and low and the record for every date at Safford Municipal (SAD), since 1998. The line marks today.

Normal daily high and low temperature at Duncan through the year, in °F, with the record for each date.0255075100125JanFebMarAprMayJunJulAugSepOctNovDec
  • Normal low
  • Normal high
  • Record high
  • Record low

Normals for Sep 24

Normal high
88°F
Normal low
53°F
Record high
100°Fin 1998
Record low
47°Fin 2017
Chance of a wet day
12%
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
January60°F25°F79°F (1999)13°F (2007)0.94 in4.00.5 in24.66930
February65°F29°F88°F (2026)4°F (2011)0.84 in4.00.0 in19.55120
March73°F33°F100°F (2026)17°F (2002)0.50 in3.00.0 in15.13791
April81°F39°F99°F (2012)25°F (2023)0.17 in1.40.0 in6.717915
May89°F47°F109°F (2005)36°F (2010)0.29 in1.50.0 in0.537130
June98°F57°F113°F (2021)50°F (1998)0.25 in1.90.0 in0.01380
July98°F66°F115°F (2020)58°F (2004)1.68 in6.80.0 in0.00512
August96°F65°F113°F (2020)57°F (2002)2.18 in7.00.0 in0.00467
September91°F56°F107°F (2020)47°F (2017)1.21 in4.50.0 in0.04260
October81°F43°F101°F (1998)28°F (2009)0.71 in3.10.0 in3.112636
November69°F31°F90°F (2020)16°F (2006)0.64 in2.90.0 in17.84491
December59°F25°F77°F (2025)17°F (2003)1.00 in3.90.5 in25.47110
Year80°F43°F10.41 in441.0 in1133,0911,801

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.

10.4 in in a normal year, most in August.

Chance of a wet day

The chance of at least 0.01 inch of precipitation on each date at Duncan, in percent, and of at least 0.1 inch of snowfall.0510152025JanFebMarAprMayJunJulAugSepOctNovDec
  • Chance of a wet day
  • Chance of snowfall

Snow

NOAA 1991-2020 snowfall normals for Redrock 1 Nne, 35.3 km away; Duncan keeps no snowfall normals.

1.0 in of snow in a normal year.

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Duncan. 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 April 24 and the first fall freeze around October 25, a growing season of about 183 days.

Median at 36°F
last May 5, first October 17
Median at 32°F
last April 24, first October 25
Median at 28°F
last April 7, first November 2

Frost dates, growing season and degree days

Humidity and comfort

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

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

MonthDew pointHumidityDryComfortableHumidMuggyOppressiveMiserable
January23°F52%100%0%0%0%0%0%
February24°F49%100%0%0%0%0%0%
March25°F42%100%0%0%0%0%0%
April25°F32%100%0%0%0%0%0%
May28°F27%100%0%0%0%0%0%
June34°F24%97%3%0%0%0%0%
July52°F43%55%34%11%0%0%0%
August54°F48%48%44%8%0%0%0%
September47°F45%81%17%2%0%0%0%
October35°F42%99%1%0%0%0%0%
November27°F45%100%0%0%0%0%0%
December23°F53%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 October, with the sky 29 percent covered on average; the cloudiest is July, at 55 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 10.7 mph at 10 meters (33 feet) above the ground.

Daylight and sunshine

The longest day is Jun 17, with 14 h 19 min of daylight; the shortest is Dec 20, with 9 h 59 min.

Hours of daylight at Duncan 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 Greenlee 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 Greenlee County: 78.0°F (+4.7 °F against 1991-2020), the 2nd warmest in 132 years on record.

August 2026 in Greenlee County: 2.46 in (-0.73 in against 1991-2020), the 46th driest in 132 years on record.

January to August 2026 in Greenlee County: 62.7°F (+3.9 °F against 1991-2020), the warmest in 132 years on record.

January to August 2026 in Greenlee County: 9.10 in (-2.09 in against 1991-2020), the 35th driest in 132 years on record.

Warmest August
78.4°F in 2020
Coolest August
67.8°F in 1968
Wettest August
5.66 in in 1988
Driest August
0.69 in in 1924

Every year since 1895

Each year's average temperature in Greenlee County against the 1991-2020 average, in °F, 1895 to 2025.-4-20+2+41900192019401960198020002020NOAA NCEI Climate at a Glance

Arizona climate and rankings

Month pages

The weather in Duncan 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 1998. 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 USC00022754 (Duncan), public domain. Records: NOAA GHCN-Daily, station USW00093084, 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 2026-09-25. Sun and moon: computed with the NOAA solar equations and Meeus. Rankings: NOAA NCEI Climate at a Glance, public domain.