Data sources & licenses
Last updated: October 2026
Thank you to everyone who publishes this data. This site is independent and is not affiliated with or endorsed by any of them.
Data
| Source | Used for | License / terms |
|---|---|---|
| National Weather Service API | Forecasts, current conditions, alerts | U.S. government open data |
| NOAA National Centers for Environmental Information | 30-year local weather history | U.S. government open data |
| NOAA Storm Prediction Center | Severe storm outlooks | U.S. government open data |
| NOAA National Hurricane Center (via NOAA map services) | Hurricanes and tropical storms | U.S. government open data |
| NOAA National Water Prediction Service | River gauges and hydrographs | U.S. government open data |
| USGS Earthquake Hazards Program | Earthquake locations and magnitudes | U.S. government work, public domain |
| National Interagency Fire Center | Wildfire locations and perimeters | U.S. government open data |
| U.S. Drought Monitor (National Drought Mitigation Center at the University of Nebraska-Lincoln, USDA and NOAA) | Drought maps | Public. Please cite the Drought Monitor |
| NOAA National Air Quality Forecast Guidance | Fine-particle (PM2.5) and smoke forecasts. The air quality index is calculated from PM2.5 using the EPA formula | U.S. government open data |
| Iowa Environmental Mesonet (Iowa State University) | Radar images (NEXRAD) | Free to use |
| Open-Meteo | Forecast layers on the weather map | Data licensed CC BY 4.0. Free API for non-commercial use |
Maps
| Source | Used for | License / terms |
|---|---|---|
| USGS The National Map | Satellite (imagery with the US Topo overlay) and topographic backgrounds | U.S. government work, public domain |
| © OpenStreetMap contributors | Street background, and place search through Nominatim | Open Database License (ODbL) |
Software we use
This site is built with open-source software. Their license texts are included in third-party-licenses.txt.
- Leaflet: BSD 2-Clause license
- Chart.js (and @kurkle/color): MIT license
- SunCalc: BSD 2-Clause license (sunrise, sunset and moon calculations)
Corrections
If you believe something here is incorrect or missing credit, please write to mach.projectlab@gmail.com.