Arizona

Corona de Tucson, Arizona Climate

NOAA 1991-2020 normals for Green Valley, 22.4 km from Corona de Tucson

The warmest month is June, with an average high of 100°F; the coldest is January, with an average low of 36°F. A normal year brings 12.8 in of precipitation and 0.1 in of snow.

Temperature through the year

The normal daily high and low and the record for every date at Davis-Monthan Afb (DMA), since 1946. The line marks today.

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

Normals for Sep 25

Normal high
92°F
Normal low
63°F
Record high
105°Fin 2024
Record low
54°Fin 1958
Chance of a wet day
13%
Daylight
12 h 03 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
January67°F36°F87°F (1953)16°F (1949)0.78 in4.10.0 in7.44190
February69°F39°F92°F (1957)18°F (2011)0.86 in4.40.0 in4.43073
March76°F44°F102°F (2026)20°F (1965)0.58 in3.40.1 in0.618227
April82°F50°F104°F (1989)32°F (2023)0.27 in1.60.0 in0.06596
May91°F58°F109°F (2005)38°F (1950)0.18 in1.30.0 in0.08303
June100°F68°F117°F (1990)47°F (1955)0.44 in1.70.0 in0.00564
July99°F72°F114°F (1989)59°F (1992)2.86 in10.00.0 in0.00634
August97°F71°F112°F (1993)61°F (1956)2.69 in9.70.0 in0.00595
September94°F66°F111°F (2023)44°F (1965)1.70 in5.00.0 in0.00462
October87°F54°F106°F (2024)26°F (1971)0.84 in3.30.0 in0.027194
November76°F43°F94°F (2020)23°F (2010)0.51 in2.30.0 in1.819530
December66°F36°F85°F (2021)16°F (1974)1.14 in4.20.0 in9.44281
Year84°F53°F12.85 in510.1 in241,6312,909

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.

12.8 in in a normal year, most in July.

Chance of a wet day

The chance of at least 0.01 inch of precipitation on each date at Corona de Tucson, in percent, and of at least 0.1 inch of snowfall.010203040JanFebMarAprMayJunJulAugSepOctNovDec
  • Chance of a wet day
  • Chance of snowfall

Snow

NOAA 1991-2020 snowfall normals for Green Valley.

0.1 in of snow in a normal year.

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Green Valley. 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 February 25 and the first fall freeze around November 27, a growing season of about 276 days.

Median at 36°F
last March 15, first November 16
Median at 32°F
last February 25, first November 27
Median at 28°F
last February 1, first December 10

Frost dates, growing season and degree days

Growing degree days this year

Observed: NOAA GHCN-Daily highs and lows at Davis-Monthan Afb (DMA) (USW00023160), through September 22, 2026; GHCN trails the calendar by a day or more. Normal: NOAA’s 1991-2020 daily normals at the same station, NCEI’s own for base 50°F and the corn method, and for bases 41°F and 32°F computed here from NCEI’s daily mean and its standard deviation (Thom’s method).

Since January 1, Corona de Tucson has gathered 7,092 growing degree days on a 50°F base, 845 more than normal by September 22, 2026: about 34 days ahead of the normal season.

Growing degree days since January 1 at Corona de Tucson, base 50°F, against normal.02000400060008000JanFebMarAprMayJunJulAugSepOctNovDec
  • 2026, observed
  • Normal
BaseSince Jan 1Normal to dateDepartureNormal year
Base 50°F7,0926,246+845 (+14%)7,682
Corn, 86/506,1905,614+576 (+10%)7,138
Base 41°F9,4668,577+889 (+10%)10,873
Base 32°F11,85110,960+891 (+8%)14,163

Base 50°F: The common base for warm-season crops, turf and most insect models; USA-NPN’s pest forecasts use it. Corn, 86/50: Modified growing degree days for corn: highs above 86°F count as 86 and lows below 50°F as 50 (Barger 1969; Purdue Extension). Base 41°F: 5°C, the base used for cool-season crops such as alfalfa and canola. Base 32°F: 0°C, the base USA-NPN uses for its accumulated temperature maps and for its hemlock woolly adelgid forecast. A day adds its mean temperature, (high + low) / 2, above the base; the corn method first holds the high and low between 50°F and 86°F. Corn typically needs 100 to 120 of those units from planting to emergence (Purdue Extension).

With the forecast added Degree day map

Humidity and comfort

NASA POWER reanalysis, 1991-2020, for the grid cell around Corona de Tucson.

The muggiest month is July, when 10 percent of days are muggy or worse, with a mean dew point of 65°F or more.

MonthDew pointHumidityDryComfortableHumidMuggyOppressiveMiserable
January28°F48%100%0%0%0%0%0%
February28°F46%100%0%0%0%0%0%
March29°F39%100%0%0%0%0%0%
April28°F30%100%0%0%0%0%0%
May29°F24%100%0%0%0%0%0%
June33°F20%95%3%1%0%0%0%
July54°F41%43%23%25%10%0%0%
August58°F47%22%30%39%9%0%0%
September52°F43%59%21%18%2%0%0%
October38°F38%96%3%1%0%0%0%
November30°F39%100%0%0%0%0%0%
December27°F47%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 June, with the sky 23 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 9.2 mph at 10 meters (33 feet) above the ground.

Daylight and sunshine

The longest day is Jun 18, with 14 h 15 min of daylight; the shortest is Dec 17, with 10 h 03 min.

Hours of daylight at Corona de Tucson 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 Pima 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 Pima County: 89.8°F (+5.0 °F against 1991-2020), the warmest in 132 years on record.

August 2026 in Pima County: 2.49 in (+0.09 in against 1991-2020), the 60th wettest in 132 years on record.

January to August 2026 in Pima County: 74.2°F (+4.4 °F against 1991-2020), the warmest in 132 years on record.

January to August 2026 in Pima County: 6.53 in (-1.22 in against 1991-2020), the 31st driest in 132 years on record.

Warmest August
89.8°F in 2026
Coolest August
79.8°F in 1968
Wettest August
5.25 in in 1971
Driest August
0.51 in in 1950

Every year since 1895

Each year's average temperature in Pima 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 Corona de Tucson 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 1946. 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 USC00023668 (Green Valley), public domain. Records: NOAA GHCN-Daily, station USW00023160, 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.