# Climate Design Data Workflow for Los Angeles, CA

> A source-first workflow for retrieving and recording building-design climate conditions for Los Angeles, CA without mixing climate normals, code zones, and HVAC design percentiles.

- Canonical: https://harth.build/resources/climate-data/climate-design-data-workflow-los-angeles-ca/
- Last updated: 2026-08-31
- Data source: Licensed ASHRAE Climatic Design Information / Standard 169 station data plus the locally adopted energy code. Coordinates 34.0522° N (America/Los_Angeles) are approximate routing references. Figures are illustrative — confirm the representative station and current edition. Climate screening data from the [NASA POWER Climatology API documentation](https://power.larc.nasa.gov/docs/services/api/temporal/climatology/) and [exact point response](https://power.larc.nasa.gov/api/temporal/climatology/point?parameters=T2M%2CT2M_MAX%2CT2M_MIN%2CRH2M%2CPRECTOTCORR%2CWS10M&community=SB&longitude=-118.2437&latitude=34.0522&format=JSON), 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.

## Key facts

| Fact | Value |
| --- | --- |
| NASA POWER climatology | 20-year Meteorological and Solar Monthly & Annual Climatologies (January 2001 - December 2020) (API v2.9.7; LST) |
| Annual mean temperature | 17.4 °C (2 m gridded climatology; not a design percentile) |
| Highest monthly maximum | 42.3 °C (July) (monthly climatological statistic) |
| Lowest monthly minimum | -1.0 °C (January) (monthly climatological statistic) |
| Annual relative humidity | 56.7% (2 m gridded climatology) |
| Annual corrected precipitation | 0.91 mm/day (climatological daily rate) |
| Annual wind speed | 2.83 m/s (10 m gridded climatology; not a structural design wind speed) |

## Direct answer

NASA POWER's 2001–2020 climatology at the Los Angeles, CA reference point reports an annual mean 2 m temperature of 17.4 °C and relative humidity of 56.7%. The highest monthly maximum is 42.3 °C in July, while the lowest monthly minimum is -1.0 °C in January; 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 0.91 mm/day and annual 10 m wind speed is 2.83 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](https://www.linkedin.com/company/harth-build) · 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.

| Field | Required record |
| --- | --- |
| Station | Name, ID, coordinates and elevation |
| Source | Publisher, edition and licensed/public status |
| Heating | 99.6% and 99% dry-bulb |
| Cooling | 0.4%, 1% and 2% dry-bulb plus coincident wet-bulb |
| Moisture | Dew-point or humidity design condition used |
| Code | Adopted edition, amendments and effective date |

## Los Angeles, CA NASA POWER monthly climate screening table

| Month | Mean °C | Monthly max °C | Monthly min °C | RH % | Precipitation mm/day | Wind at 10 m m/s |
| --- | ---: | ---: | ---: | ---: | ---: | ---: |
| January | 12.04 | 30.39 | -1.03 | 59.46 | 2.35 | 3.41 |
| February | 12.15 | 29.53 | -0.51 | 62.98 | 2.67 | 3.20 |
| March | 13.78 | 30.51 | 1.83 | 64.06 | 1.35 | 3.00 |
| April | 15.10 | 34.58 | 2.42 | 62.71 | 0.63 | 3.04 |
| May | 17.53 | 35.03 | 6.31 | 61.70 | 0.28 | 2.78 |
| June | 20.35 | 40.47 | 8.62 | 56.98 | 0.02 | 2.54 |
| July | 23.41 | 42.29 | 12.78 | 51.54 | 0.07 | 2.40 |
| August | 23.88 | 38.76 | 12.53 | 48.63 | 0.03 | 2.32 |
| September | 23.03 | 41.53 | 11.09 | 49.58 | 0.11 | 2.36 |
| October | 19.47 | 37.66 | 6.64 | 52.22 | 0.54 | 2.62 |
| November | 15.49 | 32.95 | 1.44 | 52.50 | 0.84 | 3.01 |
| December | 11.78 | 27.57 | 0.54 | 58.41 | 2.10 | 3.33 |

![Monthly mean, maximum and minimum air temperature for Climate Design Data Workflow for Los Angeles, CA](https://efwwel0vyt9vy5so.public.blob.vercel-storage.com/images/climate-data/climate-design-data-workflow-los-angeles-ca/chart-temperature-1344.webp)

*Monthly air temperature for Climate Design Data Workflow for Los Angeles, CA, plotted from the table above.*

![Mean daily precipitation by month for Climate Design Data Workflow for Los Angeles, CA](https://efwwel0vyt9vy5so.public.blob.vercel-storage.com/images/climate-data/climate-design-data-workflow-los-angeles-ca/chart-precipitation-1344.webp)

*Mean daily precipitation for Climate Design Data Workflow for Los Angeles, CA, plotted from the table above.*

## Month-by-month climate interpretation

- **January:** mean temperature 12.04 °C is 5.32 °C below the annual mean; the monthly max–min span is 31.42 °C. Relative humidity is 59.46% (2.77 points above annual), while corrected precipitation at 2.35 mm/day is 1.44 mm/day wetter than the annual daily rate.
- **February:** mean temperature 12.15 °C is 5.21 °C below the annual mean; the monthly max–min span is 30.04 °C. Relative humidity is 62.98% (6.29 points above annual), while corrected precipitation at 2.67 mm/day is 1.76 mm/day wetter than the annual daily rate.
- **March:** mean temperature 13.78 °C is 3.58 °C below the annual mean; the monthly max–min span is 28.68 °C. Relative humidity is 64.06% (7.37 points above annual), while corrected precipitation at 1.35 mm/day is 0.44 mm/day wetter than the annual daily rate.
- **April:** mean temperature 15.10 °C is 2.26 °C below the annual mean; the monthly max–min span is 32.16 °C. Relative humidity is 62.71% (6.02 points above annual), while corrected precipitation at 0.63 mm/day is 0.28 mm/day drier than the annual daily rate.
- **May:** mean temperature 17.53 °C is 0.17 °C above the annual mean; the monthly max–min span is 28.72 °C. Relative humidity is 61.70% (5.01 points above annual), while corrected precipitation at 0.28 mm/day is 0.63 mm/day drier than the annual daily rate.
- **June:** mean temperature 20.35 °C is 2.99 °C above the annual mean; the monthly max–min span is 31.85 °C. Relative humidity is 56.98% (0.29 points above annual), while corrected precipitation at 0.02 mm/day is 0.89 mm/day drier than the annual daily rate.
- **July:** mean temperature 23.41 °C is 6.05 °C above the annual mean; the monthly max–min span is 29.51 °C. Relative humidity is 51.54% (5.15 points below annual), while corrected precipitation at 0.07 mm/day is 0.84 mm/day drier than the annual daily rate.
- **August:** mean temperature 23.88 °C is 6.52 °C above the annual mean; the monthly max–min span is 26.23 °C. Relative humidity is 48.63% (8.06 points below annual), while corrected precipitation at 0.03 mm/day is 0.88 mm/day drier than the annual daily rate.
- **September:** mean temperature 23.03 °C is 5.67 °C above the annual mean; the monthly max–min span is 30.44 °C. Relative humidity is 49.58% (7.11 points below annual), while corrected precipitation at 0.11 mm/day is 0.80 mm/day drier than the annual daily rate.
- **October:** mean temperature 19.47 °C is 2.11 °C above the annual mean; the monthly max–min span is 31.02 °C. Relative humidity is 52.22% (4.47 points below annual), while corrected precipitation at 0.54 mm/day is 0.37 mm/day drier than the annual daily rate.
- **November:** mean temperature 15.49 °C is 1.87 °C below the annual mean; the monthly max–min span is 31.51 °C. Relative humidity is 52.50% (4.19 points below annual), while corrected precipitation at 0.84 mm/day is 0.07 mm/day drier than the annual daily rate.
- **December:** mean temperature 11.78 °C is 5.58 °C below the annual mean; the monthly max–min span is 27.03 °C. Relative humidity is 58.41% (1.72 points above annual), while corrected precipitation at 2.10 mm/day is 1.19 mm/day wetter than the annual daily rate.

Harth retrieved this point climatology from NASA POWER API v2.9.7 for location record us:los-angeles-ca. 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](https://harth.build/resources/climate-data.md)
- [ASHRAE / IECC Climate Zones Explained (Zones 1–8, A/B/C)](https://harth.build/resources/climate-data/ashrae-climate-zones-explained.md)
- [Heating & Cooling Design Temperatures (99%, 1% / 0.4%)](https://harth.build/resources/climate-data/heating-and-cooling-design-temperatures.md)
- [Climate Design Data Workflow for San Diego, CA](https://harth.build/resources/climate-data/climate-design-data-workflow-san-diego-ca.md)
- [Climate Design Data Workflow for Las Vegas, NV](https://harth.build/resources/climate-data/climate-design-data-workflow-las-vegas-nv.md)
- [Building Permits in Los Angeles, CA (LADBS Overview, 2026)](https://harth.build/resources/permits/building-permits-in-los-angeles-ca.md)
- [Sun Path & Solar Angles for Los Angeles, CA](https://harth.build/resources/solar-data/sun-path-and-solar-angles-los-angeles-ca.md)

## Sources and method

Licensed ASHRAE Climatic Design Information / Standard 169 station data plus the locally adopted energy code. Coordinates 34.0522° N (America/Los_Angeles) are approximate routing references. Figures are illustrative — confirm the representative station and current edition. Climate screening data from the [NASA POWER Climatology API documentation](https://power.larc.nasa.gov/docs/services/api/temporal/climatology/) and [exact point response](https://power.larc.nasa.gov/api/temporal/climatology/point?parameters=T2M%2CT2M_MAX%2CT2M_MIN%2CRH2M%2CPRECTOTCORR%2CWS10M&community=SB&longitude=-118.2437&latitude=34.0522&format=JSON), 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](https://power.larc.nasa.gov/docs/services/api/temporal/climatology/)

- [power.larc.nasa.gov](https://power.larc.nasa.gov/api/temporal/climatology/point?parameters=T2M%2CT2M_MAX%2CT2M_MIN%2CRH2M%2CPRECTOTCORR%2CWS10M&community=SB&longitude=-118.2437&latitude=34.0522&format=JSON)

## Frequently asked questions

### What does NASA POWER climatology show for Los Angeles, CA?

For the Los Angeles, CA reference point, the 2001–2020 NASA POWER climatology reports 17.4 °C annual mean temperature, 56.7% relative humidity and 0.91 mm/day corrected precipitation. The monthly maximum peaks at 42.3 °C in July.

### Can the Los Angeles, CA climatology replace project design temperatures or an hourly weather file?

No. The Los Angeles, CA response is gridded monthly climatology; its lowest monthly minimum of -1.0 °C in January is not a code percentile or observed site extreme. Verify elevation, local exposure, the required weather file or design-condition source and the current adopted code.

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