Climate Design Data Workflow for Tucson, AZ

Direct answer

NASA POWER's 2001–2020 climatology at the Tucson, AZ reference point reports an annual mean 2 m temperature of 19.8 °C and relative humidity of 37.6%. The highest monthly maximum is 44.8 °C in June, while the lowest monthly minimum is -8.1 °C in February; these are screening statistics, not code design temperatures. The point response uses LST and the 20-year Meteorological and Solar Monthly & Annual Climatologies (January 2001 - December 2020); its annual corrected precipitation is 0.88 mm/day and annual 10 m wind speed is 3.58 m/s. Use the monthly series to screen source selection before applying project design conditions. NASA POWER is gridded climatology: verify elevation, microclimate, urban exposure, station or weather-file suitability, current code edition and the authority's required source before design use.

Content and cited inputs reviewed by Harth team · Published 2026-08-17 · Updated 2026-08-31.

Which climate inputs control the design?

1. Confirm the project jurisdiction and adopted energy-code edition.
2. Select the authoritative station and record why it applies.
3. Record heating dry-bulb percentiles and cooling dry-bulb with coincident moisture conditions.
4. Keep IP/SI units, edition, observation period and retrieval date with every value.
5. Separate climate-zone envelope requirements from HVAC sizing conditions.

Tucson, AZ NASA POWER monthly climate screening table

Month-by-month climate interpretation

• January: mean temperature 10.00 °C is 9.83 °C below the annual mean; the monthly max–min span is 33.95 °C. Relative humidity is 46.37% (8.79 points above annual), while corrected precipitation at 0.79 mm/day is 0.09 mm/day drier than the annual daily rate.
• February: mean temperature 11.22 °C is 8.61 °C below the annual mean; the monthly max–min span is 38.30 °C. Relative humidity is 44.07% (6.49 points above annual), while corrected precipitation at 0.74 mm/day is 0.14 mm/day drier than the annual daily rate.
• March: mean temperature 14.91 °C is 4.92 °C below the annual mean; the monthly max–min span is 37.61 °C. Relative humidity is 36.75% (0.83 points below annual), while corrected precipitation at 0.45 mm/day is 0.43 mm/day drier than the annual daily rate.
• April: mean temperature 18.54 °C is 1.29 °C below the annual mean; the monthly max–min span is 36.26 °C. Relative humidity is 28.36% (9.22 points below annual), while corrected precipitation at 0.26 mm/day is 0.62 mm/day drier than the annual daily rate.
• May: mean temperature 23.43 °C is 3.60 °C above the annual mean; the monthly max–min span is 37.18 °C. Relative humidity is 21.97% (15.61 points below annual), while corrected precipitation at 0.13 mm/day is 0.75 mm/day drier than the annual daily rate.
• June: mean temperature 29.28 °C is 9.45 °C above the annual mean; the monthly max–min span is 32.12 °C. Relative humidity is 18.95% (18.63 points below annual), while corrected precipitation at 0.28 mm/day is 0.60 mm/day drier than the annual daily rate.
• July: mean temperature 29.40 °C is 9.57 °C above the annual mean; the monthly max–min span is 27.13 °C. Relative humidity is 42.41% (4.83 points above annual), while corrected precipitation at 2.68 mm/day is 1.80 mm/day wetter than the annual daily rate.
• August: mean temperature 28.65 °C is 8.82 °C above the annual mean; the monthly max–min span is 24.37 °C. Relative humidity is 46.78% (9.20 points above annual), while corrected precipitation at 2.08 mm/day is 1.20 mm/day wetter than the annual daily rate.
• September: mean temperature 26.37 °C is 6.54 °C above the annual mean; the monthly max–min span is 29.82 °C. Relative humidity is 42.95% (5.37 points above annual), while corrected precipitation at 1.34 mm/day is 0.46 mm/day wetter than the annual daily rate.
• October: mean temperature 20.93 °C is 1.10 °C above the annual mean; the monthly max–min span is 37.44 °C. Relative humidity is 37.48% (0.10 points below annual), while corrected precipitation at 0.47 mm/day is 0.41 mm/day drier than the annual daily rate.
• November: mean temperature 15.02 °C is 4.81 °C below the annual mean; the monthly max–min span is 38.82 °C. Relative humidity is 38.53% (0.95 points above annual), while corrected precipitation at 0.48 mm/day is 0.40 mm/day drier than the annual daily rate.
• December: mean temperature 9.72 °C is 10.11 °C below the annual mean; the monthly max–min span is 33.50 °C. Relative humidity is 46.19% (8.61 points above annual), while corrected precipitation at 0.86 mm/day is 0.02 mm/day drier than the annual daily rate.

Harth retrieved this point climatology from NASA POWER API v2.9.7 for location record us:tucson-az. It is a reproducible screening dataset, not an hourly weather file, forecast, code design condition or substitute for local professional review.

Where can you explore related guidance?

• Explore all climate data guidance
• ASHRAE / IECC Climate Zones Explained (Zones 1–8, A/B/C)
• Heating & Cooling Design Temperatures (99%, 1% / 0.4%)
• Climate Design Data Workflow for Albuquerque, NM
• Climate Design Data Workflow for Las Vegas, NV
• Sun Path & Solar Angles for Tucson, AZ

Sources and method

Licensed ASHRAE Climatic Design Information / Standard 169 station data plus the locally adopted energy code. Coordinates 32.2226° N (America/Phoenix) are approximate routing references. Figures are illustrative — confirm the representative station and current edition. Climate screening data from the NASA POWER Climatology API documentation and exact point response, retrieved 2026-08-31; source period: 20-year Meteorological and Solar Monthly & Annual Climatologies (January 2001 - December 2020). NASA POWER values are gridded screening statistics, not code design conditions or guaranteed local observations.

Source links

• power.larc.nasa.gov

• power.larc.nasa.gov